[[quoteright:250:http://static.tvtropes.org/pmwiki/pub/images/XCOM_Enemy_Unknown_Game_Cover_9093.jpg]]
[[caption-width-right:250:From the makers of ''VideoGame/{{Civilization}}''... comes a game about civilization's last stand.]]

->''Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying.''
-->-- '''Creator/ArthurCClarke''', opening quote for ''Enemy Unknown''

''XCOM: Enemy Unknown'' is a reboot of the original ''VideoGame/XCom'', developed by Firaxis Games and published by [[Creator/TakeTwoInteractive 2K]]. It was originally released on PC, {{Xbox 360}} and PS3 on October 9, 2012. A [[{{Macintosh}} Mac OS X]] version[[note]]bundled with the ''Elite Soldier Pack'' and ''Slingshot'' {{DLC}} and called the ''Elite Edition''[[/note]], was released on April 25, 2013, while an {{iOS}} [[SoftwarePorting port]] was released on June 20, 2013. A PC-only UpdatedRerelease called the ''Complete Edition'' was released on March 7, 2014, and includes all {{DLC}} released up to that point, including ''Enemy Within''.

[[NextSundayAD In the year 2015]], Earth comes under attack by alien forces. In response, the Council of Nations activates the [[TitleDrop XCOM project]], a MultinationalTeam tasked with fighting the alien invaders and researching their technology to protect humanity. The player takes the role of the [[NonEntityGeneral Commander of XCOM]], and with the help of various [=NPC=] advisers, guides XCOM [[EarnYourHappyEnding to victory]] ([[NintendoHard or defeat]]) by managing the whole organization, including base building, research, manufacturing and sending fighters to intercept [=UFOs=]. The main focus of the game, however, is on the ground combat, where the player takes control of a small squad of soldiers and fights turn-based battles against the aliens.

In combat, the player commands up to four soldiers (later upgradeable to a maximum of six). Soldiers also earn XP for kills and rank up, specializing with their first rank into one of four different classes ([[ModernDaySciFiRPGClassEquivalents Assault, Support, Heavy, and Sniper]]), each with unique weapons, equipment, and abilities. Each soldier gets two actions per turn, though using any action other than 'move' normally ends that unit's turn. Every soldier is equipped with one primary weapon, one [[EmergencyWeapon pistol]] (Heavies get a Rocket Launcher instead), and an additional piece of equipment that the player decides (such as a grenade or medikit).

Outside of combat, the player manages the XCOM base. A delicate balancing act is required, with the player having to choose what upgrade projects to research, what new weapons/items to build, what new XCOM facilities to build (such as Workshops to reduce building costs or Satellite Uplinks to increase your coverage of the world map) and what alien threats to go after, all the while managing limited resources and attempting to keep world panic down. The player must monitor the panic in various countries; if they get too high, the country might drop-out of the XCOM project and withdraw their funding (and if too many drop-out, it's an automatic GameOver).

The first {{DLC}}, titled ''Slingshot'', was released in December 2012. It added additional soldier customization options, a series of inter-connected Council missions centered on China with (among other things) a unique soldier as a reward and the chance to get certain technologies/upgrades earlier than normal. A second {{DLC}}, titled ''Second Wave'', was released in January 2013 for free (for PC, it was automatically patched in). It activated 16 previously DummiedOut difficulty modifiers, including certain options that make the game more like the original {{X-COM}} and modifiers originally considered too cruel by the developers to include.

An expansion named ''XCOM: Enemy Within'' was released in November 2013[[note]]as a regular ExpansionPack[=/=]{{DLC}} for PC and Mac, and an UpdatedRerelease called the ''Commander Edition'' for PS3 and {{Xbox 360}}, which also includes the previous {{DLC}}[[/note]]. In addition to adding more enemy types, maps, items and customization options, it added several new features, such as the ability to [[BioAugmentation genetically enhance]] XCOM troopers, a new XCOM unit called the [[MiniMecha Mechanized Exoskeletal]] [[{{Cyborg}} Cybersuit Trooper]] and a new alien resource called Meld. It also introduces a new enemy faction: EXALT, a paramilitary human group who seeks to acquire and use alien technology to TakeOverTheWorld. Unlike the open warfare waged by the aliens, EXALT resorts to cloak and dagger tactics, such as increasing panic and stealing XCOM's resources, forcing the player to respond by conducting counter intelligence and collecting information to bring them down.

A character page is under construction '''[[Characters/XCOMEnemyUnknown here]]. Please add all character- and class-specific tropes there!'''

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!!Prepare for deployment, Trope One:

* ActionGirl: Lots and lots of them. From every corner of the globe. And without any pointless {{Fanservice}} too.
* AdamSmithHatesYourGuts: In ''Enemy Within'', the prices of constructing plasma weapons have been jacked up to encourage capturing them from the aliens. This doesn't apply to interceptor armaments, meaning a regular plasma rifle now costs about four times the price of a heavy ship-borne plasma cannon.
** Can be hand-waved away by claiming that it is significantly more difficult and expensive to create plasma weaponry small enough to be toted as a "conventional" weapon compared to manufacturing a cannon designed to be mounted on aircraft.
* AdaptationalBadass: The aliens' designs have been revamped and made generally more menacing.
** Floaters. They had absolutely horrible AI combined with the worst marksmanship of the aliens in the original game, as bad as some of your rookie troopers. Now, they can drop out from the sky right behind your squad's flank from almost anywhere on the map, use their unlimited flight time to their advantage to pin down your soldiers and lastly, have a significant facelift so they look like fearsome aliens with jetpacks and not [[ArsonMurderAndJaywalking a weird guy trying to look like Superman]].
** Mutons are still green and purple, but they don't look like humans in muscle suits anymore. The are much wider-framed, appear to be wearing rebreathers, and have considerably more obvious armor.
** Chryssalids will still ruin your entire day if you aren't careful, just like in the original, but they're horrible blade-legged quadrupeds instead of people in lobster suits.
* AlienAbduction: The invaders will abduct civilians from countries not under satellite surveillance, often striking multiple cities on different continents at the same time. Successfully stopping them will gain XCOM additional support from the country they save, but panic will rise in the countries they couldn't respond to (unless they're on the same continent as the successfully stopped abduction).
* AlienAutopsy: An important part of figuring out each alien type's capabilities, as well as unlocking new Foundry projects and items for Engineering to manufacture. In ''Enemy Within'', it also unlocks new genetic augmentations. The MEC Trooper's "Vital-Point Targeting" passive ability also does 2 extra damage to any alien that has been autopsied.
* AlienInvasion: Of course. Mostly an all-out attack, with some infiltration by Thin Men and [[MindControl psionic aliens]].
* AliensStealCattle: Some raids on Abductor-class alien ships will have quite a few slaughtered cattle scattered around the storage pods.
* AliensAreBastards: [[UpToEleven And how!]]
* AllYourBaseAreBelongToUs: [[spoiler: The aliens will eventually attack XCOM HQ in ''Enemy Within'', due to the aliens overclocking their mind control powers to allow the assault.]]
* AlternateContinuity[=/=]ContinuityReboot: Separate from the classic games.
* AmbiguousRobots:
** When Dr. Vahlen autopsies the Cyberdisk, she notes that while it appears to be a machine, its internals are arranged in a manner similar to organs in a living creature and it possesses what amounts to a circulatory system with plasma instead of blood. She states in her notes that she is unsure if it is a robot or a [[SiliconBasedLife silicon-based cybernetic life form]].
** The Outsiders are referred to as [[EnergyBeing "energy constructs"]] and "{{organic technology}}", but what they are ''exactly'' [[StarfishAliens is anyone's guess]]. Unlike the rest of the aliens, their presence is never explained; [[spoiler: they're also the only aliens who don't make an appearance in the Temple Ship mission.]]
* AmazonBrigade: Doable, there's even an achievement for completing a mission with only female characters.
* AncientConspiracy: EXALT is an ancient conspiracy stretching back centuries which seeks to use subversive, underhanded methods to TakeOverTheWorld. The alien invasion [[BlackShirt gives them]] [[JumpedAtTheCall the chance they need.]]
* AntiFrustrationFeatures: Normally on Ironman, you cannot restart a mission if you lose, but are forced to continue the game with the casualties and/or panic gain you've gotten. However, you can restart both the first (if the tutorial isn't activated) and last missions if you fail them. The first is so you can start over without having to set up an entirely new game, the second is because [[spoiler: the Volunteer is one of a kind ''and'' activating the Ethereal device stops all progression.]] ''Enemy Within'' also allows the [[spoiler: XCOM Base Defense]] mission to be restarted on both regular and Ironman runs.
* AnyoneCanDie: Nobody in your ground teams is truly safe from death. A single lucky plasma bolt can send your favorite and greatest soldier to an early grave, and if you're playing on Ironman, those soldiers are gone permanently.
** Played with in Enemy Within. The Secondary Heart gene modification ensures that your soldiers will always be critically wounded instead of dying when they lose all of their HP; however, anybody who doesn't have it is out of luck.
* ApocalypseHow: [[spoiler: The Temple Ship's self destruct would cause a Planetary/Physical Annihilation level event. However the Volunteer pulls a HeroicSacrifice to get it away from Earth in time.]]
* ApocalypticLog: [[http://www.ufopaedia.org/index.php?title=News_Items_%28EU2012%29 The News Ticker]], moreso if you're playing badly.
* ArbitraryHeadcountLimit: Your squad is limited to 4 members, which can be expanded to 6 with some upgrades. You can also have only one squad answering alerts at once, even if you have enough soldiers to field additional squads. It seems XCOM can't afford a second [[CoolPlane Skyranger]].[[note]]The developers have specifically stated that they limited the squad size so drastically to greatly enhance the significance of the actions the player takes. Whereas the original XCOM had 14 (later 26) possible soldiers on a mission, each with their own set of options, the new game limits you to 4 (later 6) distinct units, each with only two actions per round. Additionally, it makes the loss of a single squad member much more catastrophic.[[/note]] In addition, XCOM can only have a maximum of 99 soldiers recruited.
** ''Enemy Within'' ups the ante by including an achievement for finishing the game without EVER increasing the squad limit. It also decreases the max number of recruitable soldiers to 75.
** The limit is upped to 7 members in ''Enemy Within'', but only during Covert Ops missions where you can send a full squad to extract the single unit infiltrating EXALT.
** Greatly upped in the [[spoiler: XCOM Base Defense mission]]. In addition to 4 to 6 of your best soldiers (depending on your squad size limit), you get around 6 base security personnel, essentially Rookies with conventional weapons.
* [[ArmCannon Arm Pistol]]: Plasma Pistols as used by the Sectoids. They get converted to a more conventional layout if you manage to capture one intact and have already researched enough plasma technology to know how to modify it safely.
* ArmorIsUseless: PlayedWith to hell and back.
** The standard Kevlar armor your soldiers start out with adds a whopping ''1'' health, but better armor adds more hitpoints, can potentially increase their defense rating to equal that provided by low cover even while standing in the open, and tend to have other special abilities. However, Colonels wearing some Chryssalid chitin can potentially have more health in standard Kevlar than rookies in [[PoweredArmor Titan Armor]].
** For the aliens, their heavily-armored regular Mutons will always have less health than the physically frail Sectoid Commanders. However, the even heavier-armored Muton Elites will outdo the Commanders. Then the Ethereals, who are dressed in robes and have bodies so atrophied they can only move thanks to their psionics, can take more hits than the Elites. Finally, the [[MiniMecha Sectopods]], which are effectively walking tanks, have the largest health pool of any alien.
** ''Enemy Within'' again zig-zags back and forth. MEC Troopers, which are {{Cyborg}} torsos inside armored mechanical chassis, have some of the highest health pools in the game. However, genetically modified soldiers only have a [[SleevesAreForWimps sleeveless vest]] with combat leggings, and putting on better armor only changes the breastplate and boots while giving them the same bonuses as the full set worn by a regular soldier. Additional shoulder pads and leggings are only cosmetic options.
** Basic EXALT units tend to be about as or more durable than their XCOM equivalents while wearing only a nice suit, sometimes with a Kevlar vest over it. On the other hand, their Elites wear better body armor and have higher health as a result.
* ArtificialStupidity:
** The pathfinding AI can be odd at times. Sometimes your troops will go up a level and then drop down to get to a piece of cover that they could have just walked straight to.[[note]]This was the result of not assigning any extra move penalties for changes in height. If the shortest distance between a soldier and his destination involves climbing a mountain, he'll take it because the system considers all terrain as "flat and one level" for movement purposes[[/note]] Blithely running directly through clouds of poison rather than going around them is also common.
** Sectopods sometimes attempt [[DeathFromAbove Rocket Barrages]] while indoors, which ends exactly how you'd think firing rockets with an obvious obstruction in the way would. They also have weapons that deal splash damage (prior to ''Enemy Within''), which they'll still use on adjacent targets which results in them possibly killing themselves.
** Floaters will sometimes use their "Launch" ability to rocket directly into a position out of cover and in the middle of your squad, thereby ending their turn and painting a huge target on themselves.
** Seekers seem to be spotty on their AI, sometimes choosing not to engage any of your soldiers even when they're under fire from their own allies, or suddenly attacking when the immediate area is clear of enemies and your whole team is on Overwatch (specifically waiting for a Seeker attack).
** In Terror! missions, aliens will sometimes ignore wounded soldiers [[SkewedPriorities and target harmless civilians]], allowing the same soldier who would have been dead otherwise to shoot them dead the next turn.[[note]]This isn't necessarily ''stupidity'' so much as ''odd priorities'': different aliens have different priorities when it comes to Terror missions. Floaters and other aggressive, relatively-unintelligent units will attack civilians because they're much easier targets, and their mission is "kill civilians". Mutons, Elite Mutons, and other high-thinking units will ''generally'' (but not always) take a shot at XCOM soldiers if their chance to hit is approximately the same as hitting a nearby civilians. Essentially, the Mutons recognize the threat XCOM presents, and will fight back effectively (or kill civilians if they can't fight back effectively), while terror units will gladly slaughter whatever's nearby.[[/note]]
** For whatever reason, aliens always skip their turn when under suppression or seeing soldiers on Overwatch, at least if they don't have an easy shot. This happens even if they're being flanked at the moment (and the possible death from reaction fire is preferable to the certain death next turn), [[ExplosiveStupidity or if they're hiding behind a car]] '''[[EveryCarIsAPinto THAT IS ON FIRE]]'''. Fixed as of ''Enemy Within'', for the most part.
** AI troops have a tendency to, on occasion, move to a position to outflank one of your soldiers or hit someone standing in the open... and then use up their remaining action to move somewhere else instead of shooting, despite having a great shot. This tends to be pretty rare though, so don't count on it happening as a matter of strategy.
** EXALT members are fond of using ZergRush, even if the numbers ''aren't'' on their side. Apparently, capturing the encoder is what enables their intelligence, because if someone's not on it, their operatives will expend both of their actions to get into the area and ignore your soldiers while doing so. Since getting into cover is apparently optional, they'll often get roasted the next turn. As a result, they usually won't give half a damn about going Overwatch if they're in a good defensive position or if the vehicle they're hiding behind bursts into flames.
* ArtificialBrilliance:
** The invaders' tactical sense is remarkably complex. They make very good use of the flanking mechanic - most of a player's introduction to flanking will be by having the technique used against them (on higher difficulties). They'll also throw grenades when they can't get a decent shot, will use Overwatch themselves if they know you're there, attempt tactical retreats, and most funny of all, accidentally use up their movement turns blundering into the middle of your units leaving them without cover and ripe for the slaughter. Basically they act like GenreSavvy players, occasional missteps and all, which is why you have to be DangerouslyGenreSavvy. [[note]]For example, be wary of attempting to suppress an alien when its allies are about. On higher difficulties, the suppressed unit's allies ''will'' attempt to counter-suppress you if they lack a clear shot, freeing the suppressed unit back up to take unfettered action. Alternatively, if they have a clear shot, they will simply just blast the suppressor in the face.[[/note]]
** Thin Men in particular are very intelligent, and will actively seek rooftops and proper sniping positions from which to support other aliens, particularly when supporting "heavy" troops like Mutons.
** The invaders will also "panic" (not the in-game debuff kind) if you trounce a squad with overwhelming force. Removing all but one of the invader units in the same turn that you discover them frequently sends the survivor fleeing from your soldiers for their lives. Of course, this becomes less likely as the strength of the invader unit goes up, or if they lack the intelligence to do so (Berserkers and Chyrssalids).
** The civilians in Terror missions are miles better than the ones in the old games. They will run away from the aliens, up to and including ''diving through windows'' and ''shimmying up drainpipes'' to get away, at least after the first turn.
** Berserkers have the ability to [[BarrierBustingBlow break down some types of cover]], causing damage to any XCOM soldiers near it in the process. Berserkers tend to specifically target XCOM soldiers behind breakable barriers when possible, in order to expose them to fire from the other aliens.
** Seekers cloak and specifically wait until they can hit an XCOM soldier who is isolated from the rest of the squad.
** Aliens mind controlling troops will often have them run towards your own soldiers and then use explosives to damage their pawn along with their target. Either it forces you to kill the mind controlled soldier, or it weakens them for when the mind control wears off, a win-win scenario.
** EXALT troops [[HoistByTheirOwnPetard use all of your favorite tactics]]: Grenades to destroy cover, smoke to protect their allies, splitting up and flanking, using rooftops to position their snipers....
* AsskickingEqualsAuthority: As your soldiers do well, they get new abilities and get promoted up through the ranks. Anyone who has reached [[ColonelBadass Colonel]] is a ''true'' badass.
* AsskickingPose: The aliens will usually strike one upon discovery. Especially the Thin Men [[CardCarryingVillain make poses]] that would turn Main/JamesBond green with envy.
* ATasteOfPower: Used in the demo, where in the second mission, all your squad members have a couple of promotions each and several pieces of equipment like Medikits, unlike in the full game, which has a squad of Rookies with 1 Heavy and just frag grenades. They face Floaters and Thin Men during the mission too, not just Sectoids.
* ATeamFiring: A missed shot will go high and wide typically especially amusing at point-blank range. However, because the game selects a random trajectory originating from a gun's barrel (which doesn't preclude the shot actually firing straight), coupled with the random nature of the miss animations, this trope can also subvert itself as a shot visually hits a target but [[NoSell has no effect]]. Became the norm come ''Enemy Within''.
* AttackDrone: On both sides of the fray.
** The aliens' Drones are multipurpose flyers that can repair mechanical units or fire a relatively weak energy pulse, and can also self-destruct. The Cyberdiscs are apparently half-mechanical, half-organic combat units. The Sectopod is a huge mechanized weapons platform, packing mortars and [[WaveMotionGun beam weapons]] galore. ''Enemy Within'' adds the Seekers, their only unit which has an InvisibilityCloak, who favor going after isolated soldiers and strangling them.
*** The Drones can also be hacked with the Arc Thrower (after relevant research) and used to repair ''your'' {{Attack Drone}}s. This is only for the duration of the mission, though.
** You get your own in the form of the SHIV (Super Heavy Infantry Vehicle), with a whole tech tree dedicated to them. They function exactly like the tanks of yore, including, in one case, functioning as portable cover. There are three varieties, Basic, Alloy (which can be used as low cover) and Hover (which can fly).
* AttackReflector: Ethereals can reflect your attacks with their mental powers, though the reflected attack only does 2 damage regardless of what was fired at the Ethereal.
* AuthorityEqualsAsskicking: High ranking units on both sides are nastier than their lower ranking counterparts.
* AwesomeButImpractical: Alloy S.H.I.V.s and potentially MEC Troopers can be used as partial and full-cover, respectively, but the usefulness of this function is mainly against weaker aliens. Due to the prevalence of [[GrenadeSpam grenade-happy]] enemies in the late game, who will always use one if two or more soldiers clump together, having a soldier take cover behind their S.H.I.V. or MEC compatriot practically waves a "Throw Grenade Here" sign at the aliens.
* BadassBoast: Soldiers and special characters have many badass lines when activating their abilities and taking actions.
* BadassCrew: A team of experienced soldiers turn into this, mowing down the aliens with ease.
* BadassInANiceSuit: Thin Men (especially in higher difficulties) can mess you up to kingdom come in early game. All while wearing their fine navy blue suits. The EXALT operatives also wear business suits, because they're civilians in day jobs who take up terrorism on the weekend.
* BadassNormal: Regular soldiers without any fancy psionics, cybernetics and/or bio-augmentations, once they gain enough experience. All they have are their skills, guns, and armor.
* BarrierBustingBlow:
** Berserkers are fond of pulling this. If there is a full-sized wall between them and an XCOM soldier, they will charge through the wall and deal an insane amount of damage. Unless the soldier is wearing endgame armor, you'd better make a spot on the Memorial Wall.
** [=MECs=] armed with the Kinetic Strike Module can do this as well, and ''much better'' than Berserkers, hitting for a whopping 12 points of damage (or 18, with upgrades; enough to instakill a Muton Elite). Even better, it's one of the first modules you can get on a basic MEC suit; nothing that you come across can take that much damage until you get to Cyberdiscs and Berserkers (the Mechtoid can take it, but only just, and they're pretty rare in the early game).
* BaldOfAwesome[=/=]BaldWoman: An option for your soldiers, male and female. Also, due to helmets and hats counting as hair styles, they're removed when off-duty, so you'll see a large number of shaved-head soldiers in the barracks if you like using them. The latter is changed as of ''Enemy Within'', and soldiers wearing helmets as hairstyles are no longer bald underneath, being given one of the conventional hairstyles while off duty in the barracks.
* {{Bathos}}: No matter the situation, the [[CoolHat fedora]] from ''Enemy Within'' looks out of place. Put it on a [[MiniMecha MEC Trooper]] for extra hilarity.
* BattleshipRaid: Naturally, whenever you attack a downed Battleship-class UFO. They're so large that there is nothing else on the Battlescape; the Skyranger lands ''on the Battleship itself''.
** The ''Slingshot'' {{DLC}} adds a raid on a Battleship ''still in flight''.
* BeamSpam: You get the option for this with with the Scatter Laser, Heavy Lasers and [[AttackDrone SHIVs]][=/=][[CoolPlane Interceptors/Firestorms]] equipped with Laser Cannons.
* BeatThemAtTheirOwnGame:
** Mind-controlling aliens are a nasty surprise, able to turn the tide of battle in one turn. However, you can start producing your own psionics, and with a high-Will psi-soldier with Psi Armor and Mind Shield, you can start reliably mind-controlling those same aliens in return. There's even an achievement for doing this to an Ethereal, the strongest alien psionic.
** One of the achievements in ''Enemy Within'' has the player [[InvokedTrope Invoke]] this, requiring you to kill a [[TheBerserker Berserker]] with a MEC Trooper's RocketPunch.
** Another achievement requires you to [[SniperDuel kill an EXALT Elite Sniper with one of your own snipers]].
* BeefGate: The game throws several of these at you to ensure you're not resting on your Research laurels. You should have lasers by the first Terror Mission so you can reliably two-shot Chryssalids, Carapace by the Mutons to resist their firepower...
* BenevolentConspiracy:
** The Council Of Nations is this, in spite of their nature as the OmniscientCouncilOfVagueness. They fund and support XCOM in their efforts to protect Earth and save its citizenry from the Alien invasion, and there's no evidence that they're up to any shenanigans on the side - [[ParanoiaFuel although]] [[SequelHook they could simply be hiding it very well...]]
** It is hinted that [[spoiler: the aliens themselves, or at least the Ethereals, may see themselves as this. They seek to push humanity to the next level, so that they may attain psychic ability to prepare them for "what lies ahead", whatever that means.]]
** Averted with EXALT. There is nothing benevolent about them.
* TheBerserker:
** Mutons, with their ally-boosting Blood Call ability.
** The aptly-named Berserker, an [[SuperToughness extremely durable breed of Muton]] that has the ability to [[TheJuggernaut charge through the environment]] to get to your soldiers. They also get a free (short) move towards one of your soldiers after ''any'' attack hits it. Fortunately, they charge blindly rather than stick to cover. A clever commander can exploit this, forcing them to trigger Overwatches and step into your other soldiers' line of sight.
* BetterToDieThanBeKilled: Members of EXALT in ''Enemy Within'' cannot be captured for interrogation like most aliens can. If you shock them with the Arc Thrower, they'll stab themselves with a syringe full of poison before they lose consciousness, so they don't risk revealing information damaging to their operations.
* {{BFG}}: The MEC troopers in ''Enemy Within'' use their superhuman strength to carry comically enormous guns. The basic MEC weapon is a giant [[GatlingGood minigun]]; as your technology advances, you can equip your MEC troopers with electromagnetic railguns and, finally, particle cannons which basically deal instant death to anything smaller than a Sectopod.
* BigBad: In contrast to the original game, where the aliens were led by an "Alien Brain", [[spoiler: the Ethereals, led by the Uber-Ethereal, are very much the bad guys here. They're the guiding intelligence behind the invasion and the various alien species are the other species that they conquered first, in an attempt to find/create a species that is both physically strong and psionically gifted. It's never made clear what what they need this for, but they do mention that it's in preparation for "[[BiggerBad what lies ahead]]"]].
--> '''[[spoiler: Uber-Ethereal]]''': ''"Behold [[MyGreatestFailure the greatest Failure]]... of [[spoiler: the Ethereal ones]]. We who failed to ascend as they thought we would. We who were cast out. We who were doomed to feed on [[PsychicPowers the Gift]] of lesser beings... as we sought to uplift them... to prepare them... [[SequelHook for what lies ahead]]."''
* TheBigBoard: A pair of them. The Big ''Hologlobe'' (a giant [[ExactlyWhatItSaysOnTheTin holographic globe]]), which sits in the middle of the Operations Center in the XCOM headquarters. All missions available are shown on this, along with tracking the movements of [=UFOs=], interceptors, and the Skyranger. The other is the world map in the Situation Room, which tracks the panic levels of all the contributing countries and keeps track of satellite coverage and council requests, as well as info on EXALT in ''Enemy Within''.
** The raid on EXALT HQ in ''Enemy Within'' shows that EXALT has a Hologlobe of their own...but it's red.
* BioAugmentation: One of the new additions in ''Enemy Within''. You can, for instance, make your units able to pull the InASingleBound trope, or make them immune to panic and resistant to mind control.
* BlackBox: Most of the technology that the Science and Engineering departments come up with is this. They have no idea how exactly it all works[[note]]Mostly because understanding the specifics isn't particularly necessary in the middle of the war; presumably, Vahlen plans to do more in-depth studies if XCOM wins the war[[/note]], but they can replicate it.
* BlackShirt: EXALT is apparently made of these. They've been vying to TakeOverTheWorld for decades, and the political instability plus technological advancement opportunities provided by the aliens gave them just the opportunity they needed.
* BlackSpeech: The language of the aliens sounds like Satan's autodial, complete with VoiceOfTheLegion. The Chryssalids and Mutons add insectile chittering and monstrous bellows, respectively.
* BlastingItOutOfTheirHands: Higher level Snipers can do this if "Disabling Shot" is chosen, forcing the target to waste a turn on unjamming the weapon. Be cautious though, as they can still use grenades just fine.
* BlindedByTheLight: Possible in ''Enemy Within'', thanks to flashbang grenades becoming available. Enemies caught in its radius take severe aim and movement penalties, though robots and certain psionic enemies are immune.
* BlingBlingBang: As of ''Enemy Within'', changing a soldier's armor tint also changes their weapon's color. This can be realistic as a soldier gets a woodland-color gun to match his woodland camouflage, but dressing your soldier in [[RummageSaleReject hot pink with yellow highlights]] will result in an equally ridiculous weapon.
* BlownAcrossTheRoom: In ''Enemy Within'', anyone killed by an attack will be sent flying. If there's an easily destructible object (like a door) behind them, expect them to go flying hard enough to break it.
* BodyArmorAsHitPoints: The primary benefit of armor, though some models also reduce the enemy's chance to hit. Certain special items like Nanofiber Vests or Chitin Plating also boost health. Additionally, a soldier who receives less damage than the health bonus given by their armor won't need a stay in the infirmary after the mission.
* BondOneLiner: Every time a soldier successfully stuns an alien.
-->''"Looks like you're coming home with us."''
-->''"Not so tough now, are ya?"''
** There is also a hilarious variant if the stun attempt goes wrong and the alien is still standing afterwards:
-->''"Permission to use a REAL weapon, sir!"''
* BonusDungeon: Taking down and salvaging a Fusion Core from a Battleship-class UFO isn't necessary to complete the game, but you do get some sweet technology for doing so, including [[InfinityPlusOneSword the Blaster Launcher]].
** BraggingRightsReward: That said, by the time you can successfully shoot down and clear a Battleship-class UFO, you don't ''need'' a Blaster Launcher or a Fusion Lance.
* BossInMookClothing: Sectopods were always tough bastards, but this goes to ludicrous degrees in ''Enemy Within''. With a trait that reduces ''all'' incoming damage by 50%, this doubles their effective health to ''60'', while simultaneously {{Nerf}}ing "HEAT Ammo", which is their main counter. Even the final boss goes down faster than one of these bad boys!
** Unless you ''enjoy'' fighting four Sectopods in one terror mission you'd better not dawdle too long in the end-game!
* BookEnds: The game's opening begins with civilians watching as alien-built abduction devices fall to Earth as meteors. The game's final cutscene depicts [[spoiler: the blasted remains of the destroyed Temple Ship falling to Earth as shooting stars while Earth's citizens look up in wonder.]]
* BoomHeadshot:
** The first ability Snipers earn, which increases the chance of a critical hit and increases the critical damage dealt based on the tech level of the rifle used.
** Shots that hit their target in general seem to be aimed towards the target's head. This is no guarantee that the shot will kill the target, however.
* BoringButPractical: "Telekinetic Field". You have to forgo the more interesting "Mind Control" ability to get it, but it gives a Defense bonus equal to full cover that stacks with other Defense bonuses for all soldiers within its wide area of effect.
* BottomlessMagazines: {{Downplayed}}. Your squad members have infinite ammo supplies, but they have to regularly reload their primary weapons. Ammo is not tracked 'per shot', but in chunks - and certain abilities (such as Suppression) use up more ammo than a normal attack. Played straight with [[EmergencyWeapon pistols]] though, they never need to be reloaded at all.
** Played straight visually when using "[[PinnedDown Suppression]]". Until the turn is over, the soldier/alien using it won't stop firing, even if they've fired more than the magazine/powercell can allow. This is especially obvious with the "Training Roulette" Second Wave option from ''Enemy Within'', where [[ImprobableUseOfAWeapon Sniper Rifles and Shotguns]] can be used to suppress enemies.
* BridgeBunnies: Inverted. All bridge personnel is male and very similar looking. (Except for one unseen French speaking woman in the tutorial.) They must have forgotten about female background characters altogether.
* BulletTime: Slo-mo effects occur when a reaction shot is triggered.
* ButThouMust: The tutorial mission helps you familiarize yourself with most of the mechanics of the game by taking your hand and telling you exactly what to do, guiding you to have all but one of your squad horrifically murdered. If you should play the tutorial again, there is absolutely nothing you can do to prevent this course of events, and the best you can do is skip the tutorial altogether.
* BystanderSyndrome: News blurbs in low-panic countries can report how tourists ''are attracted'' to locations with reported UFO sightings. Eventually {{averted}}, they start caring more as the panic rises and the Terror! missions become more frequent, with the same news blurbs mentioning how some countries' tourism industries evaporated overnight.
* CallBack:
** The report for the "Meld Recombination" research project mentions that Dr. Vahlen found a bunch of redacted files from the 1960s. ''The Bureau'', anyone?
** There's a strong implication that [[spoiler: EXALT is the remnant of the 1960s XCOM, or is at least modeled after it for whatever reason. Note their old-style outfits and conspicuous backpacks.]]
* CameraAbuse: The camera lens frequently gets spattered with gore during autopsies.
* CantCatchUp: EXALT eventually goes this way. Though their operatives field superior gene mods, they never reverse-engineer plasma weaponry or advanced armor, staying stuck on the laser/carapace tech level.
* CassandraTruth:
** One news report states "UFO enthusiasts around the world feel sense of vindication following appearance of aliens."
** New blurbs from countries at low panic will mention how reported alien sightings or people killing aliens are met with skepticism and accusations of drug usage, despite, you know, the whole alien invasion. This borders into GenreBlindness if the country was panicking previously but has since calmed, but eventually {{averted}} as panic rises.
* CategoryTraitor: The Council and Bradford specifically calls EXALT "traitors" rather than just enemies. For once, it's {{justified}} as they're [[TheQuisling humans trying to help the aliens conquer humanity]].
* CelebrityParadox: One of the EXALT base location hints says that "It is/isn't in a country you can play in [[VideoGame/{{Civilization}} Civilization V]]," another game made by Firaxis. If it's not breaking the fourth wall, it confirms that Firaxis exists in this universe. One must wonder what their critically-acclaimed game released in 2012 must have been.
* ChangingGameplayPriorities: Your first upgrade can be either weapons or armor. At this stage in the game, your weapons are still killing enemies in one shot, so upgrading armor is more important. By the late game, RocketTagGameplay begins to emerge and you need to upgrade your weapons to keep from being outgunned.
* CharacterCustomization: You can [[http://img.photobucket.com/albums/v348/CFace/uXx3k.jpg customize]] the visual appearance and names of the soldiers. Every soldier. All of them. The ''Elite Soldier Pack'' also allows you to customize the colors of their armor and includes alternate looks for standard XCOM body armor and Carapace Armor. ''Slingshot'' and ''Enemy Within'' add various types of headgear, as well as alternate looks for the other available armors.
** It might have been even more involved at some point in development too, possibly having rookie soldiers with shiny untainted armor that would be altered as they rose through the ranks, [[http://img.gawkerassets.com/img/183381vipswskjpg/original.jpg adding some wear and tear and personal designs,]] much like actual soldiers.
* ChameleonCamouflage: Mimetic Skin works this way in ''Enemy Within''. If no aliens see their starting point (and would see the pattern moving), the soldier basically gets ghost cloaking if they move to full cover. It does disable the stealth mode of both Ghost Armor and Ghost Grenades even if Mimetic Skin isn't active at the time.
* CherryTapping: Often necessary to capture aliens alive. While the most fragile of them can be taken down with just the [[StaticStunGun Arc Thrower]], the stronger ones need to be weakened first, which often necessitates that the squad pull its punches and intentionally use weak attacks to get them just low enough on health for it to work. Using the standard-issue sidearm pistols you start the game with (the weakest kind of firearm available) are often ideal for chipping away until a foe is at ''just'' the right number of hitpoints.
* ChestBurster: [[http://img.gawkerassets.com/img/183383iprrtqsjpg/original.jpg Chryssalids.]]
* ChestOfMedals: {{Downplayed}}, but you can still give your soldiers up to 5 medals in ''Enemy Within'', and they actually give them useful bonuses.
* CloneArmy: The alien troops are collections of genetic and cybernetically modified clones from a variety of species under the control of the Ethereals.
* ColonelBadass: Colonel is the highest rank a character can achieve, and since ranks work essentially as levels, any Colonel you have is automatically this.
* ColorCodedForYourConvenience: The tech levels. Ballistics are khaki, Lasers are red and Plasma is green.
** The option to change the color of soldiers' armor means that a player can manually do the same for his soldiers' classes, making them easy to identify at a glance.
* CombatMedic:
** Any soldier you give a Medikit can qualify, though the Support class' abilities make them best suited for this role.
** Thanks to the "Training Roulette" modifier in ''Enemy Within'', any soldier has the potential to gain both the "Field Medic" and "Savior" ability, letting them heal as well as properly-specced Support Colonels in normal games.
* CommonTacticalGameplayElements: Being a tactical game, ''Enemy Unknown'' implements most of these: Fog of War, Scouting, High Ground, Unit Specialization, Panic, Attack Range, Flanking, Attack of Opportunity, Friendly Fire, Taking Cover, Covering and Suppressing Fire, Called Shot (Snipers only), Target Spotting, Defensive Stance (Hunker Down command), Crowd Control (Assault's extra reaction shot against nearby enemies), Concealment (Ghost Armor), Smoke Screen, Grappling Hook (Skeleton Suit and Ghost Armor), and Movement Manipulation (Assault's flush-from-cover shot).
* TheComputerIsACheatingBastard: Though the alien AI is quite intelligent and generally plays by the same rules, they do get a few one-sided advantages.
** Enemy units get a free move to nearby cover (In ''Enemy Within'', Cyberdisks, Mechtoids and Sectopods will go into Overwatch instead, while Seekers cloak before moving) when they are first spotted by one of your soldiers, unless said soldier is hidden by terrain or cloaking. This is to guarantee they can get into cover so they won't be easy kills, but they still get the free move even when it's already their turn, though they will be unable to do anything else for that turn either way. Needless to say, [[MyRulesAreNotYourRules your soldiers don't get the same luxury]], but luckily, they still trigger Overwatch.
*** This can be partially circumvented using the Ghost Armor, or, in ''Enemy Within'', the Mimetic Skin gene mod or the Ghost Grenade. Any of these allows the cloaked unit to discover alien pods without automatically granting them their move to cover. Now, if you have a Heavy or grenade-launching MEC-trooper in range, you can remove those annoying packs of floaters and thin men in their entirety as they stand about, or give a Squadsight Sniper a free shot to pick off a dangerous unit standing out of cover.
*** Melee aliens often won't use it to get into cover; they use it to get closer, even if they used their turn to get into visual range. If you're extremely unlucky, you'll spot them on the final move of your turn, and they use their free move to get very cozy with their next victim. [[ThisIsGonnaSuck Cue 'Alien Activity']]...
** An unfortunate bug can cause aliens to spawn right within your group entirely without reason or warning. This is due to the fact that enemy 'patrols' in the fog of war are nothing more than the groups of aliens sitting in a small group, waiting several turns, and then instantly teleporting to a different location on the map instead of actually moving around like they should.
*** Fixed as of ''Enemy Within'': aliens now move around the map as they should, with defined, consistent positions every turn. You can even manipulate their movement with the Mimic Grenade to draw unseen enemies to a specific area of your choice.
** In general, alien units follow the same rules you do: they can move twice, move once and shoot, shoot to end their turn, or move and set up Overwatch. Sectopods, being giant, massively armed war machines, can shoot twice and still catch your soldiers with reaction fire (but only if they don't move) in a single turn. Combined with their massive HP totals (more than any other unit in the game) and extremely high defense (-30% to be hit), they're incredible devastating when you encounter them, breaking the rules you've been following for the whole game. [[spoiler: And the final mission throws TWO of them at you at once! Fortunately this is why the Volunteer was given [[LastDiscMagic the "Rift"]].]]
** While they generally manage to rein in the AI's knowledge of your position, certain enemies like Thin Men seem to have the uncanny ability to run exactly the right distance to enter your field of view (and subsequently, theirs) to fire on your troops ''without'' provoking Overwatch shots, which only trigger when an enemy in sight ''leaves'' the square they are currently in.
* ConcealmentEqualsCover: ZigZagged. Seemingly played straight, as all forms of cover only provide a Defense bonus (which reduces the chance of being hit) rather than reducing or stopping damage entirely, and can be shot through by any kind of weapon when the target using it is hit, essentially meaning all cover in the game is really being valued by their ability to provide concealment against shots. This means large garbage cans provide better cover than a low stone wall, and a bar tap or cash register is the difference between half- and full-cover. Averted by how nearly all cover can be destroyed by explosives or taking a direct hit by laser/plasma weapons, which makes it very clear the only purpose of the cover in the game is to provide concealment against enemy shooters. Inverted for conventional ballistic weapons when they shoot and don't hit their targets as the shots go into cover like the aforementioned large garbage cans, as bullets would logically tear through such materials.
** Mostly kept the same in ''Enemy Within'', though weapons can destroy cover even if the shot hits the target (previously, cover would be left completely unharmed if the shot hit the target) and heavier ballistic weapons, like [=LMGs=] and Sniper Rifles, can now destroy certain types of cover much like laser and plasma weaponry.
* ConservationOfNinjutsu: A pair of mutually exclusive Assault class abilities have higher benefits for having multiple enemies in sight. "Tactical Sense" increases the Assault's Defense, while "Aggression" increases their critical hit chance instead.
* ContinueYourMissionDammit: If you're planning to unlock everything, you'd better be prepared for the Council to occasionally tell you to get the lead out on those story missions.
* CoolChair: EXALT has one in their headquarters. It is a huge ornamented throne-like affair, which is of course located in front of a huge holographic projection of the whole world.
* CoolPlane:
** The Firestorm, which can take on ''Battleships'' one-on-one and win. Dr. Shen, even with all the other cool gear he's built, says the Firestorms make him the most proud. Your NumberTwo also comments that humans have just leveled the playing field when he first sees it.
** There's also the trusty Skyranger, which can bring your squad anywhere on the planet and back in a few hours at most.
** The regular Interceptors are pretty cool too. They can take on highly-advanced [=UFOs=] without any reverse-engineered alien tech on them and ''win''.
* CoolShades: With the DLC packs, soldiers get an option to wear these into battle. The added [[CoolHat beret]] just enhances the coolness.
* TheCorruption: In ''Enemy Within'', you'll have to be careful with all those genetic and cybernetic modifications, as things can ''happen'' to your soldiers when you use the aliens' Meld technology to genetically and cybernetically enhance them... [[GameplayAndStorySegregation at least, in story. They're perfectly safe to use as much as you want in gameplay]].
* CosmeticAward:
** Mission ratings. While it's nice seeing Excellent across the board, the ratings themselves don't actually ''mean'' anything in-game, aside from the logical extensions of what losing troops (self-explanatory) or not killing all of the aliens (mission not completed and causes panic) hurting your ratings in their categories means. The exception is Terror missions, though, since the Civilians Saved rating affects how much panic is reduced afterwards.
** Achievements.
* {{Cosplay}}: PlayedForLaughs in a news report from Japan as [[TheScapegoat a cover-up]]. It reads, "Alleged alien abduction in downtown Tokyo has been blamed on [[FunnyMoments costumed anime enthusiasts]]."
* CoupDeGraceCutscene:
** If the cinematic camera triggers for an attack that kills someone, especially the Chryssalids' and Berserkers' melee attacks.
** In ''Enemy Within'', killing a Berserker, Mechtoid or Sectopod with the MEC Trooper's Kinetic Strike Module brings up a unique cutscene where the MEC Trooper beats them down.
* CrapsackWorld: The in-game [[http://www.ufopaedia.org/index.php?title=News_Items_(EU2012) News Reports]] depict a grim picture of the world as panic starts to rise. Economic collapse, unchecked rioting, destroyed infrastructure, and starvation become common reports later in the game.
* CreatorCameo:
** One of the structures you can build is named after {{X-COM}}'s original creators, the Gollop brothers (Julian and Nick). It is also mentioned that said structure was designed by a "pair of brilliant young brothers".
** The Thin Men's facial features are based on SidMeier himself.
** Some of the {{Hero Unit}}s are based on Firaxis or 2K staff.
* CreatorProvincialism: Zig-zagged. Most of the time, in regular abduction, crash, terror! and equally run-of-the-mill missions, the battlefield will always look distinctly American. For instance, fighting in urban London will take place among (right-handed, naturally) black-white police car wreckages with red-blue lights, yellow cabs and [[EverybodyOwnsAFord Ford station wagons]], crash sites "near the German border" occasionally look like the New Mexico desert, and Tokio will be crowded almost exclusively by white and black people. But scripted story missions, like the tutorial in Cologne and the rendez-vous in Hong Kong are usually ''surprisingly'' faithful to their locations, often including unique buildings, cars, [[{{NPC}} NPCs]] and even ''traffic signs''. Though admittedly, they actually made Cologne ''[[InvertedTrope prettier]]'' than it actually is (you won't find many cobblestone streets and baroque houses there anymore).
* CriticalExistenceFailure:
** XCOM soldiers and the aliens, as well as EXALT soldiers in ''Enemy Within'', will continue fighting at full strength even if they're down to one hit point, though the former does take some temporary Will penalties. Can be averted for the former if the "Red Fog" Second Wave option is enabled.
** The XCOM project itself, if more than eight nations withdraw. You could be winning battles left and right with the best technology available, but skimp on the satellite coverage and you'll [[spoiler:receive [[http://www.youtube.com/watch?v=BNXGktfGm1Q a message]] from the Council spokesman, not so subtly being manipulated by the aliens, that the entire project was a mistake and will be shut down.]]
** {{Exaggerated}} in ''Enemy Within''. Now whenever someone is attacked, they always flinch as the projectiles slam into their body. If they suddenly realize they don't have enough health to survive the assault, they'll [[RagdollPhysics go limp]] and [[BlownAcrossTheRoom be sent flying]].
* {{Crossover}}: The ''Brave New World'' expansion for ''VideoGame/{{Civilization}} V'' allows you to recruit XCOM Squads, end-game airborne infantry[[note]]they can be dropped within 40 hexes using the Skyranger. For comparison, the regular paratroopers can only be dropped within 9 hexes.[[/note]] that can take on even the [[HumongousMecha Giant Death Robot]], the strongest unit in that game. Each squad member wears Titan Armor[[note]]Oddly, dropping them from a Skyranger has them using jetpacks like on Archangel Armor to slow their descent, which aren't modeled on the in-game unit[[/note]] and packs a Heavy Plasma.
* CrutchCharacter:
** The [=SHIVs=] are faster, tougher, better-armed and more accurate than [[RedShirt Rookies]], with mind control immunity and a variety of additional benefits to boot, but are outmatched by [[AuthorityEqualsAsskicking high-ranking meatbags]] and can't rescue civilians during Terror missions. Nevertheless, their usefulness is such that many strategies for Classic and Impossible difficulties involve rushing to get them out the door ASAP. They're also extremely useful for the final mission, as they can cheerfully laugh off almost everything the Ethereals can throw at them. [[spoiler:Watch out for the "Psionic Lance" and "Rift" attacks, though, they'll likely one-shot the SHIV.]]
** The Argentinian Heavy, the SoleSurvivor of the tutorial mission. He's your first non-rookie, but he's nothing special in terms of stats.
* {{Cyborg}}:
** Floaters are more machine than flesh, especially the Heavy variant, as are the Mechtoids added in ''Enemy Within''. Most of the other aliens are also this, though not nearly to the same degree.
** XCOM MEC Troopers from the ''Enemy Within'' expansion, to an almost disturbing degree. The process for creating an MEC Trooper requires that they voluntarily amputate their arms and legs, have parts of their torso replaced with machines, and for battle, that they climb into monstrously large battle suits that are armed to the teeth.
* DamageIncreasingDebuff: The "Shredder Rocket" ability available for Heavies. It causes enemies in the blast area to take 33% more damage from all sources for four turns, at the cost of doing less damage compared to a normal Rocket (though it still destroys cover). The debuff is not very useful early on (though a second rocket is), but potentially much more so later in the game when you start facing tougher enemies.
* DamageSpongeBoss: Come ''Enemy Within'', Sectopods have an effective 60 Health, incredible damage output, and don't bother using cover due to possessing a permanent ''full'' cover bonus. [[BossInMookClothing Have fun]].
* DangerouslyGenreSavvy:
** The aliens have shades of this [[spoiler:despite the GoneHorriblyRight aspect of their plan]].
*** Reverse-engineering the enemy's technology is a staple of the {{X-COM}} franchise. In this game, alien weaponry is programmed to self-destruct when the wielder dies.
*** XCOM needs to prevent alien activity in its member countries to keep panic low and maintain its funding. What do the aliens do? Regularly arrange for multiple Abduction missions on different continents at the same time, forcing XCOM to focus their efforts on one and let the others proceed unopposed.
*** Those satellites you need to scan for alien activity? The aliens will actively attempt to track and shoot them down.
** EXALT knows [[EnhancedInterrogationTechniques exactly what's going to happen]] to any member who gets caught, and know that secrecy is their best weapon. So they will all [[BetterToDieThanBeKilled commit suicide rather than be captured alive]]. [[spoiler: Except for the one who does come into custody, but that was before XCOM knew that EXALT existed and likely before those secrecy protocols were instated as well]].
* DeaderThanDisco: Humorously, can be said InUniverse when soldiers report kills.
* DeathFromAbove: The Sectopods' "Rocket Barrage" attack. Though it takes a turn to charge up and offers you a chance to escape, it also can happen if the Sectopod is out of sight, meaning you often won't get a chance to.
* DecoyProtagonist: Delta Squad. They all have names (all soldiers do) and get to speak, but 3/4ths of them get killed before the tutorial mission is over.
* DefiantToTheEnd: It's possible to invoke this if you're losing. In addition, the scene of [[spoiler: XCOM HQ if you lose the Base Defense mission]] looks like [[spoiler:XCOM, Bradford in particular,]] put up one hell of a fight before going down.
* DeathOrGloryAttack: A common tactic for players is sending a soldier out into the open in order to get a better shot or flank an enemy. Hopefully, the shots connect and the enemy will be too busy being dead to attack the exposed soldier. If it goes wrong, the alien is still alive at the end of the turn and retaliates, or you accidentally expose another group of aliens that proceed to cut down your trooper.
** This is essentially the entire design philosophy and MO of the Assault soldier.
* DespairEventHorizon: Occurs to the populations of countries as the panic level maxes out. News reports state how many people give up hope for victory, and turn to religion, anarchy, or hunkering down in their homes. If the country then withdraws from the Council, they won't return from the brink.
* TheDevTeamThinksOfEverything:
** Not only is there an achievement for bringing Zhang from ''Slingshot'' to the final mission, but on the off chance that he both develops psychic ability and is chosen as the Volunteer, [[spoiler: he has his own unique voiceover when he shouts for the rest of the team to flee when he is about to commit his HeroicSacrifice.]]
** The "Site Recon" Council mission in ''Enemy Within'' features [[spoiler:Chryssalids and Zombies]]. Depending on whether or not [[spoiler:Zombies]] have been encountered before, Bradford either matter of factly says, ''"Looks like we got [[spoiler:Chryssalids]],"'' or a somewhat panicked ''"What the hell is that thing?"'' when the squad comes across the first [[spoiler:Zombie]]. It's very specific as well: if you've seen [[spoiler:Chryssalids]] but ''not'' [[spoiler:Zombies]], then you'll get the ''"What the hell is that thing?!"'' message.
* DevelopmentGag:
** The logo appears to be de-hyphened, much like ''The Bureau''. But if you [[http://www.xcom.com/enemyunknown/index.html look at the negative space in the last three letters]]...
** Ditto for the title itself; it's a combination of the original game's two titles (''X-COM: UFO Defense'' and ''UFO: Enemy Unknown'').
* DifficultButAwesome: The Basic Shotgun for the Assaults. While the Assault Rifle would be a better choice in the lower difficulties, it is a must in Impossible. In the Impossible difficulty an instant kill is worth its weight in gold, and the Assault Rifle cannot reliably provide that, (even with a flank!) while the Shotgun can. The Shotgun however requires careful placement of your Assault so that he's up in the face of one alien while concealed from the rest, which requires knowledge of how the cover and concealment mechanic works.
** Multiple high-tier MEC Troopers are this, due to how prohibitively expensive it is to field a single suit. 10 Meld to convert a soldier into a MEC Trooper, 40 Meld to build the basic Warden suit, 60 Meld to upgrade that into the Sentinel, and ''100 Meld'' to upgrade that into the Paladin. All told, it's a staggering ''210 Meld'' to field a single, fully upgraded MEC Trooper, which is a substantial amount, given that you can only collect 20 units of Meld during most missions. However, it's definitely worth it if you can collect enough Meld, as you get a LightningBruiser capable of taking on anything the aliens can throw at you.
** Fully gene-modding a soldier is also this. Depending on the options you take, five gene mods can cost between 150 to 200 credits and 80 to 150 Meld. They'll also take 15 days to go from unmodded to fully modded. However, when that's done with, you have a superpowered badass on your hands who can form an absolutely deadly duo with your MEC or regular troops.
* DifficultySpike:
** Normal? Not too hard. The next difficulty up, Classic? Murder. Aliens are all professional snipers and your rookie soldiers aim like they're blind, which makes getting them ''beyond'' rookie rather... difficult.
** Even Impossible is a gigantic leap up from Classic. Sure, if you can beat Classic you know how to properly play, but now the Sectoids are too beefy to be killed by a single grenade, not to mention your soldiers are now frail enough to be killed by a single plasma bolt. Likewise, the Thin Men and Floaters are now also too tough for the Shredder Rocket to kill them anymore.
** The first Terror mission is a massive leap in difficulty from anything that has come before, especially if the player has no upgraded weaponry or armor yet.
** Your first encounter with the sheer power of enemy Psionic abilities (outside of the "Mind Merge" ability of Sectoids, which only affects them, as well as Mechtoids in ''Enemy Within'') sets the stage for the second half of the game. Now, not only do you have to upgrade your weapons and armor to stay relevant against increasingly better armed and armored enemies, but you also need to quickly develop Psionic abilities of your own if you want to stand a chance. [[spoiler:Of course, this was the entire reason behind the invasion.]]
** In the early game, the rush becomes to get as many satellites as possible up in the air, so that you can stop running out of credits. When you finally manage to do so, you quickly find out that ''you can no longer launch satellites to lower panic''. This can result in extremely tense moments, waiting for a Terror mission, or hoping that the next abduction doesn't include one of the countries already on the brink of panic.
* DirtForcefield:
** Played with. Your troops can run in the dirt or in muddy water, get wounded several times by aliens, survive explosions that blow walls apart, and walk in scenes of abominable carnage where walls have been repainted with litres of human and/or alien blood, but whatever they do, they will (mostly) look pristine and immaculate. Dirt, dust, and sweat never touch them. However, if they take more damage than their armor can handle, blood splatters will immediately appear on their uniform.
** Played straight for the aliens, including species like Chryssalids and Berserkers, whose greatest hobby is ripping people apart with bare hands/claws/blades.
* DisadvantageousDisintegration: Using explosives to kill aliens prevents you from salvaging anything other than the alien's corpse after the mission, denying you weapon fragments that you could use in research projects or the foundry.
* DiscOneFinalBoss [[FinalBossPreview Preview]]: You first see the [[spoiler: Sectoid Commander]] during the tutorial mission. The next time you see it is when you're kicking down its front door during the [[DiscOneFinalDungeon Alien Base Assault]].
* DiscOneFinalDungeon: The "Alien Base Assault" story mission is, as far as the characters know at the time, a raid on the aliens' central headquarters on Earth, and is more unusual and more difficult than other missions to that point, complete with a DiscOneFinalBoss at the end. Events shortly thereafter reveal this to be a mere staging area for the {{Alien Abduction}}s, rather than their primary command center.
* DiscOneNuke:
** MEC Troopers in ''Enemy Within.'' You're able to get your first one in as little as ''21 days'', long before your first Terror mission[[note]]If you research "Meld Recombination" immediately, it has a time requirement of 8 days. Assuming you don't get scientists with your first abduction mission, you will then be able to build the Cybernetics Lab in 10 days, and augment a soldier in 3. If you get engineers and/or scientists, it can be done even faster[[/note]], they require only a relatively modest initial investment of Meld and money, and they have significantly more health and firepower than your rookies. You would need to research other things for many weeks before you'd be able to build lasers or carapace armor, so they're likely your first real power upgrade (gene mods don't really increase your ability to kill enemies, they just provide other nice benefits). Their only flaw is they're too big to TakeCover, but they provide enough power and defense to keep the rest of your rookies alive long enough to level up. If you upgrade them and keep their weapons up to date however, they can become downright [[GameBreaker Game Breaking]], as few enemies (even later on in the game) can withstand their attacks.
** "[[SuperpowerLottery Training Roulette]]" can be this trope ''if'' you get lucky. Your soldiers unlock a random ability after being promoted, and that pool includes the game-breaking Colonel abilities. Potentially, a mere Corporal could have access to "In The Zone," a Lieutenant can heal as well as a support Colonel, and a lucky soldier can get "Will To Survive", which reduces damage by 2 when not flanked against enemies that usually do only 2 damage.
* DoingResearch: Very important throughout the whole game, as new aliens with different abilities and equipment keep showing up as the invasion progresses. Performing an AlienAutopsy will provide more info when the alien is examined on the battlefield.
* DoubleMeaningTitle: ''Enemy Within'' can be interpreted as referring to two of the major additions, namely BioAugmentation (Gene-mods use alien tissue, meaning the ''enemy'' is literally ''within'') and/or EXALT (Human collaborators, the ''enemy within'' humanity's ranks).
* DoubleTap: While Snipers have an ability with that name, the credit actually goes to the Assault class's Rapid Fire ability, which shoots the enemy twice in quick succession.
* DoWellButNotPerfect:
** If you've managed a perfect run in ''Enemy Within'' without adding a single name to the Memorial Wall, prepare to abandon your flawless streak if you want to acquire the Defender's Medal, which requires a squad death to unlock and 5 more for the remaining medals. Mandatory if you're going for certain achievements.
** Capturing aliens for interrogation and leveling new recruits, as both require you to get aliens down to a sliver of health. Arc Throwers can only capture aliens at low health, and since the majority of experience is awarded from kills, you want your rookies to land the killing blows on enemies if you want promotions to arrive at a decent rate. In both cases, it's detrimental if a high-ranking soldier randomly scores a critical hit that finishes off your selected target.
* DownloadableContent: Aside from releasing the pre-order ''Elite Soldier Pack'' bonus to the public, there's:
** The ''Slingshot'' Content Pack, which includes a special series of Council missions and additional customization options for the XCOM troopers.
** The free ''Second Wave'', which includes 16 difficulty modifiers, some of which must be unlocked by completing the game on certain difficulties.
* DramaticGunCock: Snipers dramatically reload their ballistic bolt-action rifles after each cinematic shot, complete with a casing flying through the air in slow motion.
** OneHandedShotgunPump: Assault-class soldiers do this after each cinematic shot... even if it's a ''laser'' shotgun. You gotta wonder if they added the pump to the Scatter Laser [[RuleOfCool just for that]] (no other laser weapon has one).
* DumbMuscle: Mutons fit the trope to a tee. They're physically imposing and have strong tactical knowledge, but aside from that, they're thicker than an asphalt milkshake and have no effective independence or initiative, depending on their mental programming instead. Fittingly, they have a Will score so low that any psychic soldier will easily mop the floor with them.
* DropShip: The Skyranger is a crude one. Though it doesn't seem to actually go into space, the speed at which it moves around Earth does suggests that it's using sub-orbital spaceflight. In its role, however, it fits the trope like a glove.
* DummiedOut: Within days of the official release, enterprising programmers discovered some mostly-finished functions that weren't implemented in the final game. These include the ability to intercept Terror Ships and Abductors before they land, making it possible to avoid the associated Terror and Abduction missions altogether. Modders have managed to reactivate some of these options, and others have since been officially patched back in.
* EarlyBirdBoss: The ''Slingshot'' {{DLC}} pits you against Mutons with full-sized Plasma Rifles rather than the Light variant, usually well before you'd expect to have the weapons or armor needed to have a good chance against them.
** Even earlier in the same DLC, you're pitted against a ''Chryssalid''.
** Continuing the trend, you can encounter a Cyberdisk after the previous two.
* EarlyGameHell: Until you get some upgrades, don't expect your soldiers to do much more than die horribly unless you're good and/or lucky. Even harder is finding the time and money to build anything in your base.
* EasyLogistics: Much easier compared to the original ''{{VideoGame/X-Com}}''. Ammunition is never a matter you need to personally provision, and aircraft fuel is managed for you behind the scenes. About the only things you need to manage supply-wise are the quantity of XCOM-original advanced weapons/accessories that you research and produce, as all conventional human weapons/supplies are readily available.
* ElaborateUndergroundBase:
** The XCOM Project's headquartered in one. Instead of the classic top-down view flat base, this game uses a side-view multi-level base nicknamed the "Ant Farm". Unlike the original game, this is the player's only base; the developers noticed most VideoGame/{{X-COM}} players focused on a single base and built others solely to expand their radar range, which is done via launching satellites in this game.
** [[spoiler: The aliens have one too, using it as a gathering points for specimens from all the {{Alien Abduction}}s they have been doing. It forms a DiscOneFinalDungeon early in the game.]]
* EleventhHourSuperpower: For the final mission, [[spoiler: the Volunteer gets a powerful area of effect attack called the "Rift".]]
* EliteMook: The Muton Elites, of course, as well as EXALT's gene-modded Elites in ''Enemy Within''.
* ElitesAreMoreGlamorous: In this case, it's ''all'' of XCOM that are the Elites. XCOM is the special unit that gets the critical missions, the best equipment, and ends up booting the aliens of the planet. In the meantime, the appearances of the regular Earth militaries are restricted to requests for gear to not get curb-stomped, flavor text stating how they're getting curb-stomped, and missions showcasing how they're getting curb-stomped.
** This is accentuated during the [[spoiler:defense of the main base]], where you have access to XCOM base security as well as a few of your standard operatives. The difference is... stark, to say the least. The base security is little better than your standard recruit, and by this point in the game you're fighting things like Chryssalids and Sectoid Commanders.
* EmpoweredBadassNormal: Your super-soldiers, who started off as mere rookies and can now MindRape aliens to death, [[InASingleBound leap over entire buildings]] with their genetic enhancements, or operate a MiniMecha that {{Rocket Punch}}es aliens to death.
* TheEngineer: Dr. Shen and everyone else in Engineering. There's also a military Combat Engineer, Sergeant Carlock, in a Council mission.
* EnhancedInterrogationTechniques:
** XCOM "interrogates" alien captives. We aren't shown the details (as a shutter closes when interrogation starts), but it involves two arms radiating some energy, getting information straight out of the alien's brain and lots of sedatives. Also, the subject ''never'' survives the process and you always get their corpse added to your stockpile after the interrogation.
** After the first Sectoid interrogation, Dr. Vahlen is asked how exactly they interrogated an alien who speaks a language nobody understands. She replies that they stuck probes into its brain and read what signals they could until it died. ''Yikes''.
** Not to mention South America's continent bonus - "[[WeHaveWaysOfMakingYouTalk We Have Ways]]", making both Interrogations and Autopsies instantaneous, banking on the reputation of [[BananaRepublic certain South American dictatorships]] and their employment of these.
* EscortMission: Target Extraction Council missions. Unlike just about every other game ever, the Escort is fully controllable and has a special ability that raises their defense, though only if they're in cover.
** Which is strange in the case of one potential escort, who protests loudly about being extracted against his will by XCOM while the aliens gleefully shoot at him.
* EveryCarIsAPinto: Justified by how many laser and plasma weapons are getting thrown around. Plasma weapons can one-shot modern tanks, after all. Typically, they have to be set on fire first before that happens, which also gives both the XCOM troopers and aliens one turn to get away from it, though explosives will immediately cause it to blow up. Furthermore, stray missed shots from plasma and laser weapons can set vehicles alight, even from across the map, leading to seemingly inexplicable explosions a turn or so after an alien barely misses a running operative with reaction fire.
** On the other hand, (almost) [[EverybodyOwnsAFord Every Car Is a Crown Victoria]], from Moscow to Miami.
* EvilCounterpart:
** Mutons have been described like this, an alien SEAL Team Six to fight your own troops. For starters, they're equipped with Alien Grenades, and they ''will'' use them on groups of your XCOM troops.
** EXALT from ''Enemy Within'': a pro-alien terrorist group that uses the same classes, equipment and abilities as XCOM and ''also'' reverse-engineers alien technology as the campaign goes on.
* EvilLaugh:
** Psionic troopers will sometimes break out an absolutely ''blood-curdling'' one when using the Mindfray ability on enemies. [[GoneHorriblyRight Makes you wonder]] if Dr. Shen is [[HeWhoFightsMonsters right]]...
** All of the aliens celebrate their accomplishment when they kill someone, but the Heavy Floater always seems particularly amused with himself after he blows away one of your soldiers or a civilian with his plasma rifle.
* EvilMakesYouUgly: EXALT genetic modifications exceed even Dr. Vahlen's ethical limits, and it shows. Elite EXALT operatives display deep wrinkles, sunken eyes and some even have greenish skin discolorations. Their regular operatives aren't in much better shape either.
* ExcitedShowTitle: Terror! missions, when aliens attack a bunch of civilians you need to rescue, always have an exclamation point. When trying to load a save, it reads, "Terror attack in [X]!"
* ExecutiveSuiteFight: [[spoiler: EXALT's headquarters is in a luxurious penthouse on a skyscraper, so naturally the raid plays out like this trope]].
* ExposedExtraterrestrials: The Sectoids.
* FaceDeathWithDignity:
** Out of all of the aliens that get interrogated, the Thin Man is the only one who doesn't panic. He glowers at the zappy-arms and starts walking towards the glass as if he's about to say something, but the shutters close on him before he says anything.
** The Ethereal attempts this, standing aloof and dignified in the containment before it starts, but loses its composure as soon as the robot arms move in. [[spoiler: Unlike their lesser cannon fodder, the Ethereals never expected humanity to capture them, after all.]]
* FacelessGoons: You can have your own squad of them, provided you have the {{DLC}} packs.
* FastRoping: Used in the intro of a couple of story missions in ''Enemy Unknown'', and an uncommon entrance during certain regular missions in ''Enemy Within''.
* FighterLaunchingSequence: When an Interceptor, a Firestorm or the Skyranger is launched, we are treated to a cutscene of its launch. The cutscene is longer the first time it's done. Each subsequent time, only the last part of the cutscene is played.
* FinalDeathMode: Ironman mode.
* {{Foreshadowing}}:
** The Tutorial mission hints at all of the iconic alien species you'll encounter later: a soldier that has been torn open from the inside out by a ChestBurster, a zombie trapped under some rubble, and a psionically mind controlled soldier will all be warning signs to long time fans.
** Over the course of the first ''Operation Progeny'' mission, there's several to the entire EXALT faction. Bradford notes that the ambushed French soldiers were killed with ballistic weaponry, they're after a very special "[[LivingMacGuffin cargo]]," and you extract someone who is implied to be an EXALT operative, who gives cryptic hints to his organization's ideology and opinions on XCOM.
* FreezeFrameBonus: Take a good look at the map coordinates during the cutscenes showing the first downed UFO and the Alien Base's location. [[spoiler: [[EasterEgg They actually point to 2K Games' Corporate Headquarters in California and Firaxis' Game Studio in Maryland]], respectively.]]
* FrickinLaserBeams: The second tier of weaponry available to XCOM. They're not as powerful as their plasma counterparts in most cases, but they're a step up from regular ballistic weapons and ''much'' cheaper to build than plasma weapons.
* FunWithAcronyms:
** The '''S'''uper '''H'''eavy '''I'''nfantry '''V'''ehicle.
** The S.C.O.P.E. item. The game never mentions what that stands for, and it looks just like a fancy scope.
** XCOM itself is never explained in-game; it stands for e'''X'''traterrestrial '''COM'''bat unit.
** '''M'''echanized '''E'''xoskeletal '''C'''ybersuit, in ''Enemy Within''.
** In ''Enemy Within'', there's EXALT, which, like the S.C.O.P.E., never has its meaning mentioned.
* FreudianTrio: Dr. Vahlen (Id), Dr. Shen (Superego) and Officer Bradford (Ego).
* FromBadToWorse: Countries that lose faith in XCOM due to high panic levels will withdraw their funding to focus on their own defense. After which, a swirling dark vortex emerges over the country. Not only that, running covert operations against EXALT in these areas puts you in a mission where you see a lot of destruction; which heavily implies that country is essentially overrun.
* GasMaskMook: Mutons have some sort of breathing apparatus and some of the DLC helmets for your soldiers can count as well. [[SubvertedTrope However, neither protects against poison cloud attacks]]. For XCOM soldiers to have poison immunity, one must wear [[PoweredArmor Titan Armor]] (Ghost and Archangel as well in ''Enemy Within''), [[OutsideTheBoxTactic carry a Medikit]] or carry a Respirator Implant (''Enemy Within''-only).
* GatlingGood: The SHIV's and MEC Trooper's default weapon is a minigun. Interceptors can also mount a short range rotary cannon called the Phoenix Cannon.
* GameBreakingBug:
** The flight movement interface is... iffy. It's possible to get soldiers and S.H.I.V.s trapped inside objects where they can't move to escape, which in gameplay terms is like killing them (at least for the mission). If they turn out to be the sole survivor, you can't save them at all; you must abort or restart.
** Occasionally, "Disabling Shot" will fail to work on Sectopods and they will be able to fire their weapons anyway.
** Using "Disabling Shot" on an alien in Overwatch has a chance to produce the exact opposite effect. They won't be disabled at all the next turn, and then get ''unlimited'' Overwatch shots, shooting at a target each ''tile'' it moves, which can often [[CycleOfHurting doom that soldier]].
** The infamous teleporting alien bug, which can drop [[http://www.youtube.com/watch?v=B7kJi_pwj2c a Sectopod]] into the middle of your unprepared team. If you're on Ironman and get a nasty group popping up in the middle of your team, you've pretty much lost the mission unless you're really lucky.
** Using a smoke grenade in the final level on the area overlooking the two Sectopods can cause the game to freeze if the Sectopods are still alive.
* GameMod: Several, some of which have re-enabled DummiedOut functions.
* GameplayAndStorySegregation: Dr. Vahlen asserts that the hulls of alien ships must be at least an order of magnitude stronger than any currently-known material. They are easily destroyed by garden-variety hand grenades.
* GiantMook: Mutons in general, as well as Heavy Floaters. As of ''Enemy Within'', Mechtoids, which are Sectoids piloting a MiniMecha.
* GlassCannon:
** The Sniper class is decently fast but can't fire their sniper rifle at all after moving, unless a specific class perk is taken, and also has lower base health progression than the other classes. Considering their weapons have the highest accuracy and base critical rate, and that they can have an array of severely overpowered perks[[note]]For example: shoot twice in one turn, perform a headshot for ramped up crit chances, shoot an enemy from almost any distance as long as an ally can see them. Most especially with the In The Zone ability, where killing a flanked or exposed enemy does not count as an action, meaning you can clear out 3 or 4 Chryssalids and still move and take action in one turn[[/note]], it's entirely possible to kill or severely wound some of the strongest enemies ''[[GameBreaker from across the map.]]''
** Seekers are dangerous because they [[InvisibilityCloak cloak]], hide for a few turns, then incapacitate and strangle an isolated unit to death if no other soldier can reach them in time. Once they are revealed, they have pathetic HP pools for an armored robot and easily fall prey to even ballistic weaponry.
* GlobalCurrency: XCOM, no matter where in the world it's located, uses [[WeWillSpendCreditsInTheFuture Credits]] instead of the national currency of any of its founding nations. Justified in that it makes it easier to quantify and streamline the calculations of funding, supplies and logistics if a single unified currency is used instead of being forced to calculate exchange rates.
* GlowingEyes: Using a psi ability causes the user's eyes to glow [[GlowingEyesOfDoom a sinister, deep purple.]]
* GodzillaThreshold:
** Implied with Dr. Shen's NoTranshumanismAllowed stance on Psi Testing in ''Enemy Unknown''. Taken UpToEleven in ''Enemy Within'' with Gene Splicing and Cybernetics thrown on top of the pile.
** In a more meta example, explosives. Grenades and rockets are extremely powerful weapons that are available immediately, but destroy valuable alien equipment you could otherwise salvage; as a result, they are rarely used in Easy and Normal. On [[HarderThanHard Classic or Impossible,]] explosives aren't just a good idea - they're pretty much ''mandatory.''
* GoneHorriblyRight: [[spoiler: As it turns out, the XCOM project as a whole. The Ethereals invaded to motivate the creation of the project so they could weaponize the inherent versatility and {{Determinator}} outlook of the human race so we'd be useful enough to adopt as part of their alien empire and help them with ''something'' that's coming. Assuming you win, it worked too well.]]
* GoodWeaponEvilWeapon: The dimorphism between XCOM's and EXALT's weapons becomes more pronounced later on in the tech trees. At first, EXALT starts with [[DarkIsEvil black-tinted]] ballistic weapons, compared to the khaki camo your soldiers default to. For the lasers, they're black to your light gray and shaped more like typical guns than [[OurWeaponsWillBeBoxyInTheFuture your own lasers]].
* TheGreys: The Sectoids are back of course. By way of the [[http://en.wikipedia.org/wiki/Dover_Demon Dover Demon]] and VideoGame/DeusEx, by [[http://www.gameinformer.com/b/news/archive/2012/01/05/february-cover-revealed-xcom-enemy-unknown.aspx the looks of things]].
* GrandTheftMe:
** It's implied that the reason behind the alien invasion may be [[spoiler:to use humanity as the new host bodies for the minds of the Ethereals, whose current physical forms have deteriorated almost to the point of uselessness.]]
** Can be done in-game to both organic aliens and your soldiers using psychic MindControl.
* GrapplingHookPistol: A built-in version in two of the armors.
* GrenadeSpam: Possible in ''Enemy Within'' thanks to the new inventory system. A properly-specced Support could potentially bring in 3 smoke grenades and two pairs of different grenade types.
* HackYourEnemy: Drones can be hacked with the Arc Thrower once the "Drone Capture" Foundry Project is completed.
* HandCannon: Fully upgrade your pistols at the Foundry, research plasma pistols, and give them to Snipers with the "Gunslinger" ability and they will be able to kill even Mutons in one hit.
* HarderThanHard[=/=]IdiosyncraticDifficultyLevels: The difficulty levels are called "Easy", "Normal", "Classic"[[labelnote:*]]Prior to the European release and resulting patch, Classic was called VideoGame/{{X-COM}}[[/labelnote]] and above that, "Impossible", with "Classic" being meant to be the closest to the original game's difficulty (that could be achieved with the game mechanics of the 2012 remake) and "Impossible" even ''more'' difficult than that. There is also another difficulty modifier called "Ironman Mode", where the game will only have one save file for that playthrough, and will save for the player after every action during combat, meaning that if you make a mistake there is no reloading to before it happened. [[UpToEleven Now try that on Classic difficulty...]]
** Some designers also mentioned that the "Impossible" difficulty is literally supposed to be {{unwinnable}}. For most players, it's just a question of how many missions they can complete before failure. According to the staff, beating Impossible difficulty on Ironman mode is only ''theoretically'' possible. Some players have managed to pull it off, though, and as if in retaliation, Firaxis released the ''Second Wave'' {{DLC}}, which includes gameplay modifiers even they thought were too cruel. This was taken further again in ''Enemy Within'', with ''both'' Classic and Impossible difficulties getting a significant spike in toughness.
* HealingFactor: Many in ''Enemy Within''.
** The "Adaptive Bone Marrow" Leg genemod allows your soldiers to heal two HP per turn once their actual health is damaged, while also reducing their recovery time after the mission.
** EXALT Elite Medics have an ability to automatically regenerate one health per turn, which also affects nearby allies. This ties into an achievement called "[[VerbThis Regenerate This!]]", if you use an explosive device to kill them.
** MEC Troopers can choose the "Repair Servos" passive at Captain, which lets them repair 2HP per turn, up to a maximum of 6HP per mission.
** S.H.I.V.s can repair 2HP per turn after completing the "Sentinel Drone" Foundry Project.
* HealThyself: Played with. While healing items and regeneration abilities immediately replenish the lost HP, the soldier will still need infirmary time if they lost health points not added by their armor.
* HelmetsAreHardlyHeroic: Your troops normally don't wear helmets, and they aren't even available without {{DLC}}. It gets especially noticeable when they're wearing Titan armor, which has an isolated filtration system that protects against poison clouds and a built-in cooling system to protect against flames, both of which should require a helmet. The ''Elite Soldier Pack'', ''Slingshot'' and ''Enemy Within'' do add helmets as cosmetic customization options, however.
* HeroInsurance: Your troops can freely blow up anything and everything during an Abduction or Terror mission with no consequences (other than potentially destroying cover you'll need later), and even accidentally killing civilians with poorly-aimed explosives will only net you a minor reduction in the mission rating. {{Justified|Trope}}, since XCOM represents the ''only'' hope of defeating the aliens and protecting humanity, and the [[ReasonableAuthorityFigure Council of Nations]] [[GodzillaThreshold is not worried about a few hundred thousand dollars worth of damage when the flip side is the possible extinction of the species]].
* HeroUnit: You can give one of your soldiers a specific name to turn them into a powerful XCOM Hero, though this will [[NoFairCheating lock out achievements]] for that playthrough. All Heroes have 20 Health and 100 Aim and Will, unless stated otherwise below.
** SidMeier "Godfather": A Psionic Support Colonel with 200 Will and ''all'' Psionic powers available to human units, [[spoiler: even the "Rift"]].
** Ken Levine "[[{{Franchise/Bioshock}} Big Daddy]]": A Sniper Colonel with [[ImprobableAimingSkills 200 Aim]].
** Joe Kelly "Archangel": A Heavy Colonel.
** [[ShoutOut Otto Zander]] "Unbreakable": An Assault Colonel with [[MadeOfIron 100 Health]].
** [[UsefulNotes/AmericanFootball Chris Kluwe]] "Loate": A PC only Sniper Colonel. [[labelnote:*]]Was added alongside the ''Second Wave'' due to defeating ''XCOM:EU's'' lead producer, Garth [=DeAngelis=], in a ''XCOM:EU'' multiplayer match.[[/labelnote]]
** [[VideoGame/TheBureauXCOMDeclassified William Carter]] "Old Timer": An Assault Colonel added in ''Enemy Within'' with a [[NiceHat fedora]] and only 80 Will.
* HeroicSacrifice:
** [[spoiler: The Volunteer during the ending cinematic, stopping the Temple Ship from exploding into a black hole and moving away from the Earth to explode a bit less spectacularly]].
** [[spoiler:It will be a certain occurrence if any of your troops are being mind controlled when the final boss goes down, as its death will kill all units considered by the game AI as enemies. As well, troops close by the Uber Ethereal will be killed from it exploding as it dies]].
* HeWhoFightsMonsters: Dr. Shen wonders if using the aliens' technology, which turned living beings into living weapons and tools, might not cause humanity to go down the same path. Even more pronounced in ''Enemy Within'', where Meld allows the technology to be applied directly to no-longer-fully-human soldiers. However, in ''Enemy Within'' Shen is more open to using alien technology to alter humans his original voice line, expressing horror at the mutilation of the Floaters, is changed to one that expresses disquiet but doesn't rule out the creation of MEC cyborgs.
* HiddenInPlainSight: EXALT Headquarters turns out to be located [[spoiler: in a fancy skyscraper penthouse. Every Council Nation has at least several of those]].
* HissBeforeFleeing: Most of the time you stumble upon or are stumbled upon by a group of aliens, they have a mini-cutscene where they all turn around and look at you, growl, then they get a free turn to run to cover.
* [[spoiler: HiveMind: The Ethereal Collective.]]
* HoistByHisOwnPetard:
** Mutons have an ability called "Intimidate" which they use after being wounded to try to get your soldiers to panic, which will have them act randomly by moving, shooting or hunkering down and ending their turn while making them immobile and inactive for the next turn. On rare and deeply ironic occasions, "Intimidate" will cause a soldier whose already acted for the turn to panic and shoot the Muton who just used "Intimidate" dead.
** Berserkers have an ability called "Bloodlust" that makes them take a free move towards the soldier that shot at them every time they are hurt. Since they are melee only fighters, it may look like a good idea, but it ends up doing them much more harm than good. The reason is that they just get a free move, not a free ''attack'', so even if they completely close the distance and reach their attacker they can only stand next to him and do nothing until the next turn. Which they usually never live to see, since they are now standing without cover in the middle of a squad of angry XCOM soldiers who will slaughter them at short range. It is even worse if you have the "Close Combat Specialist" perk, which grants your Assault soldiers a free reaction shot against any enemy that approach them.
** The entire point of the game, really. Aliens attack Earth with vast technological superiority, and Earth fights back by ''taking'' that technology and ''improving'' on it. The Firestorm interceptor is more powerful than anything short of the [[spoiler:Temple Ship]], and aliens never field Alloy Cannons or Plasma Sniper Rifles because those are completely custom XCOM designs.
* HoldTheLine: Two variant mission types in ''Enemy Within'':
** One of the EXALT mission types involves protecting a transmitter that is feeding XCOM intel on their operations. You have to defend an encoder, which is hiding the location of the transmitter, and if the encoder is disabled by EXALT, you have to defend the transmitter itself. Once you've killed all the EXALT waves, the mission is successful.
** The other variant is [[spoiler: defending XCOM's own headquarters against multiple waves of alien invaders, and you get [[RedshirtArmy Base Defense troops]]]] to assist your squad. [[spoiler: This occurs some time after you destroy the alien base.]]
* HologramProjectionImperfection: The aliens use plenty of holographic interfaces for the computers on their ships and bases. This becomes more obvious when a character shoots through them, the holograms "shatter" and break apart, only to reform again after the air above them clears.
* HowDareYouDieOnMe: One of the upgrades from the Officer Training School is "Don't Die On Me", which increases the chances that soldiers will simply be critically wounded when their HP drops to 0. The chances go up as they become higher ranked. No longer present in ''Enemy Within'', since there are gene mods that do the same thing, only better.
* HumanResources: The aliens are kidnapping humans for their own mysterious purposes, but you can turn this around on them. Many items you can create through Engineering or the Foundry require you to use up the bodies of aliens (you're ripping out their cybernetic implants or other useful material).
* HumansAreSpecial: [[spoiler:Turns out humans share the right combination of physical toughness and psionic potential, and the aliens want to make that specialness part of their empire.]]
* HyperAwareness: The "Bioelectric Skin" genemod amplifies the soldier's latent electrical field so they can sense enemies close by, even if they have no line of sight. Useful for sensing if there's a group of enemies in the next room or finding cloaked Seekers.
* HypocriticalHumor: A captured EXALT soldier deprived of his [[CyanidePill Cyanide Syringe]] states that "XCOM is nothing but puppets..." He is, however, part of an organization that [[TheQuisling is]] ''[[TheQuisling trying]]'' [[TheQuisling to help the aliens conquer Earth]] because of the potential benefits of siding with them. Ironically, however, he's ''right'' about XCOM, [[spoiler:since XCOM is unwittingly part of the Ethereals' uplifting agenda.]]
* ICanStillFight: Unfortunately {{Averted}}. Given the desperate situation XCOM finds itself in, you'd think they'd let an injured soldier back into the fight if there's a shortage of manpower and they aren't going to collapse the moment they step out of the Skyranger. However, soldiers ''cannot'' be released from the sickbay early, even if they lost only 1 health the previous mission and only have a few hours of bedrest remaining. Painful especially when it means you have to do that Terror mission with Squaddies while your Colonels twiddle their thumbs.
* IDidWhatIHadToDo: [[spoiler: The Ethereals say this in response to ''something'' coming. They are not repentant about it, however: they did what they had to do ''because they could.]]''
* TheIlluminati:
** Despite being ruled by an TheOmniscientCouncilOfVagueness, XCOM [[{{Averted}} is not one of these]].
** On the other hand, this trope fits EXALT like a glove. They're a secret society of paramilitary operatives working in the shadows and masquerading as ordinary citizens. Each one of them is fanatically loyal to the cause and won't stop at anything to take the aliens' gifts and TakeOverTheWorld. The organization is also shown to be very old and very wealthy, their base having a lot of fancy decorations and priceless art. Their insignia even has the stereotypical Illuminati "eye"!
* ImagineSpot: How the applications of Meld are explained in ''Enemy Within''. Each scientist describes the potential applications, while cuts of MEC suits and gene-augmented soldiers in action are played.
* ImperialStormtrooperMarksmanshipAcademy: {{Averted|Trope}}, in stark contrast to the preceding titles' notorious reputation. Soldiers always shoot in the right direction and have a decent to-hit chance as long as they're within a reasonable range for the weapon they're holding. Most tellingly, grenades always go where they're supposed to. It makes you feel like you really ''are'' commanding the elite troopers that the original game ''claimed'' you were.
** Played straight for Heavies who miss with regular rocket launchers: instead of the missile veering off-course after being fired, they blatantly aim off-target and shout "Missile wide!" before even firing.[[note]]Though to be fair, they put the missiles exactly where they are supposed to go nine times out of ten, it is just really obvious on those rare occasions that they miss.[[/note]] In general, the class' Aim stat is noticeably lower than the other classes.
** Also played straight if your soldier is hit with Debuffs like "Mindfray" or being poisoned, especially if they're a rookie. Nothing like a soldier missing an enemy three meters away and being perforated the next turn.
** Weaponized in gameplay mechanics; combatants that don't use cover receive permanent cover bonuses instead, so a Sectopod can stand in the open and watch as your entire squad fails to hit a car-sized target at less than 50 feet. Presumably [[BossInMookClothing their hands are shaking with terror.]]
** {{Exaggerated}} in ''Enemy Within''. When a soldier misses a shot, they start by blatantly aiming their weapon several degrees off of their target, fire every projectile to the exact same spot, and only then report that they "missed".
* ImprobableAimingSkills: If a Sniper has the right perk and nothing blocking their shot, it's completely possible to snipe an enemy from across the map, provided an ally can see them. The sniper rifle weapon even gains accuracy farther away from targets to aid this[[note]]The sniper rifle has an effective range longer than most maps, with the only exceptions being the Battleship, Alien Base, and Temple Ship[[/note]].
* InASingleBound:
** Thin Men are able to hop right up to the tops of buildings, yet another reason they are so nasty despite being physically frail.
** Even worse, the Chryssalids with their nasty melee attack can do it too.
** Thanks to the BioAugmentation system added in ''Enemy Within'', your soldiers can be augmented to do the same.
* INeedYouStronger: [[spoiler: On a species-wide scale. The true purpose of the invasion is to test whether humans have the right combo of physical and psionic strength desired by the Ethereals, which is why the aliens gradually scale up the forces they're sending instead of curbstomping Earth with everything at once. Assuming you win, [[GoneHorriblyRight it works too well]].]]
* InstantWinCondition:
** [[spoiler:The last mission. The second you defeat the Uber-Ethereal, you win the game.]]
** You don't have to rescue all the civilians on Terror missions; if you just kill all the aliens, it still counts as a victory. Some people will just save one civvy, then let the aliens come to them, in order to avoid losing soldiers for no great benefit[[note]]The biggest and best benefit of completing a Terror mission is the panic reduction it will give to the entire region, instead of just the single country. The more civilians you save, the better the reduction. However, if you fail to save any civilians, even if the mission is otherwise successful, it will ''raise'' panic instead of ''lowering'' it, which could be catastrophic. It's almost always better to take a few risks to maximize the number of civilians saved, but panic can be reduced by other means as well[[/note]].
* InterfaceSpoiler:
** Even if you don't have line-of-sight to an area and thus wouldn't know where the enemies are (or the enemy in question is cloaked), you cannot make a move order into a square that contains an enemy. This is visible on the map.
** The cinematic camera often spoils the outcome of direct attacks; while "Overwatch" and grenade attacks usually provide a cinematic cut regardless, a standard attack only ever does so if the hit is going to both connect and kill the enemy in the next few seconds, though kills can occasionally happen without the cinematic camera triggering (much more often in ''Enemy Within''). This happens to the aliens on their shots as well, so if a firing alien gets a camera shot panning over them, the next camera shot will be of one of your troops getting killed or critically wounded.
*** Strangely enough, the game can subvert this. When using an Arc Thrower, the cinematic shot may engage, but the shock fails to incapacitate the target as it usually occurs.
*** Downplayed in ''Enemy Within'': the cinematic camera activating is no longer a guarantee of a hit. Similarly, ''not'' seeing the cinematic camera activate doesn't mean you'll miss. The game seems to determine when a particular shot is appropriately ''dramatic'' (i.e. could turn the battle around if it's a hit ''or'' a miss) and uses the camera for those.
** The achievements for upcoming {{DLC}} are uploaded to the list of global achievements on {{Steam}} before the {{DLC}} is released. They can easily be picked out by being listed as 0.1% other players getting them (aside from the usual NintendoHard ones) and don't show up on the stand alone list, and can spoil the presence of certain missions and/or enemies.
** Sectopods can launch missile barrages, but it takes them to charge for a turn to do so. When this happens, the camera centers on the machine, and then on the area it's about to bombard. The spoiler comes in the fact that the camera still moves in this fashion even when the Sectopod is outside visual range, so if you see this camera motion even if no Death-Machine is in sight, ''get the hell out of there''.
** Minor one, but after completing ''Slingshot'' and researching the Fusion Lance, the game will say it's meant for the Firestorm even if the Firestorm hasn't been theorized yet.
** Meld is referred to by name by the game labels even before it is officially dubbed as such.
** Oddly {{Subverted}} in ''Enemy Within''. When using Rapid Fire, if the first shot misses, there will be two "shot missed" indicators over the target, implying the next shot will be a miss as well... but then the next shot could still kill your target dead.
* InterserviceRivalry: {{Downplayed}}, but Vahlen and Shen make it clear that they disagree on how best to utilize Meld, preferring bio-augmentation and cybernetic enhancements, respectively.
** Lampshaded by Bradford: ''"Is there anything you ''agree'' on?"'' They hesitate, then announce that they agreed on ''the name''.
* InvisibilityCloak:
** The Overseer UFO is protected by one of these, requiring the use of the Hyperwave Relay to find it.
** Ghost Armor lets your troopers sneak around on the battlefield.
** XCOM can use Ghost Grenades to cloak several units at once in ''Enemy Within''.
** Alien Seekers in ''Enemy Within'' can cloak as well. Researching their corpses allows you to add the "Mimetic Skin" gene mod to your troopers, so that ''they'' can do it too.
* ItsTheOnlyWayToBeSure: A unique Council mission in ''Enemy Within'' called "Site Recon" has you investigate "unusual activity" in a fishing village in Newfoundland, Canada. When it turns out that the "unusual activity" is [[spoiler:a hive of Chryssalids using a whale and sharks as incubators for more Chryssalids]], Bradford decides to call in an airstrike to wipe the place off the map.
* ItemCrafting: Most of the stuff you can research or manufacture requires you to expend more than just credits, but also various resources or items you've collected from the aliens. Alien Alloys and [[{{Unobtanium}} Elerium]] are the two big ones, but you also need to use up Weapon Fragments[[note]]to rebuild the weapons from the broken pieces or study their structure to turn the technology to new ends[[/note]] and the dead bodies of aliens[[note]]to rip out their cybernetic implants to include in your new devices[[/note]] for a lot of products.
* IWantThemAlive: Used in spirit, if not actually said outright. Several objectives in the game require that aliens be taken captive rather than killed, which presents its own set of challenges since the team must take care to soften a target up without killing it, then getting into range to use an [[StaticStunGun Arc Thrower]]. However, the player may find themselves wanting to do this more often than is absolutely required, since it allows them to recover the enemy equipment intact, which is much less resource intensive than [[ItemCrafting building their own]].
** Live interrogations of aliens do not directly unlock new technology, but they cut research time in half for whole groups of technology topics; combine that with South America's "We Have Ways" for instant interrogations and you can cut months of research project time off if you regularly capture every new type of alien alive.
* JackOfAllStats: The Support class has pretty average stats all-around, as do the assault rifles they wield.
* {{Jetpack}}: On the Archangel Armor and on the Floaters. Also a piece of potential equipment on MEC suits.
* JitterCam: The camera shakes slightly during cinematic shots when your soldier bashes through a door or jumps through a window, and it's mostly noticeable [[GoodBadBugs when the shaking persists until your turn finishes]].
* JustPlaneWrong: In the Tutorial mission, a scanner identifies a downed German helicopter as a [=NH90=][[note]]which is an actual transport helicopter used by multiple nations, including Germany[[/note]], while displaying a schematic of a UH-60 Blackhawk.
* KeystoneArmy: [[spoiler:Subverted the first time and played straight and justified the second time. Bradford thinks the aliens are done after you destroy their base... which quickly turns out to be an ''outpost'' of the main force. The Temple Ship's destruction does cripple the aliens, but given how its destruction involves the deaths of most of the aliens' command staff and their leader, as well as how they were using it to supply their ships, that makes perfect sense.]]
* KillItWithFire: Fire is simply a barrier to non-Titan armored troops in ''Enemy Unknown'', unless it spreads into the square they're standing in. ''Enemy Within'', on the other hand, introduces [[FireBreathingWeapon MEC-mounted flamethrowers]], as well as an incendiary bombing run in the ending cutscene of a certain Council mission. Amusingly, MEC troopers sometimes actually say "Killing it with fire" when using their flamethrowers.
* KineticWeaponsAreJustBetter: Played With. While XCOM's ballistic weaponry is more sophisticated than our own, it's still woefully outclassed by [[WeWillUseLasersInTheFuture laser and plasma weaponry]]. Upgrading to better weapons is a must once you get past Thin Men and Floaters. On the other hand, the Alloy Cannon, essentially a shotgun that fires rounds made of alien alloys instead of more conventional materials, is better in close quarters than almost any other weapon.
* KungFuProofMook: Chryssalids, Cyberdiscs and Sectopods are immune to Stunning, as well as Seekers and Mechtoids in ''Enemy Within''. In addition, some enemies have the Hardened property, which drastically reduces the likelihood of a CriticalHit; more often than not, the reduction is big enough that you'll get a fat 0% chance to crit.
* LateArrivalSpoiler: Before the game's release, combing through the numerous preview videos and the demo revealed a lot of information ostensibly kept secret, such as (seemingly) the full roster of aliens, plot-important videos and details about autopsied alien invaders. If not careful, it's very easy to spoil yourself without trying. Given that this is a [[TheRemake Remake]] of [[VideoGame/{{XCom}} a much earlier game]], there was little expectation that these things would stay unknown to most players from the start.
* TheLawOfDiminishingDefensiveEffort: It's a game mechanic here. Units that can't TakeCover, like Sectopods and Berserkers, receive the "Hardened" ability and a huge base defense rating. This can allow them to stand out in the open and have a lower chance of being hit than enemies in cover twice the distance away.
* LeaningOnTheFourthWall[=/=]TakeThatAudience: The peanut gallery regarding the alien entertainment device you find during the assault on the alien base:
--> '''Dr. Shen:''' ''"Is this what the aliens do for fun? At least they're not playing ... computer games."''
* LeeroyJenkins: At first, the Assault's "Run & Gun" ability can seem like this... but pair it with their "Lightning Reflexes" ability, and suddenly they're sprinting up and triggering that alien's Overwatch to waste it, clearing the way for your squishier troops to come up and push through. You can invoke this as well. Got a dark room where you know aliens are? Send in a [[RedShirt rookie trooper]], with a Heavy standing by with a rocket. [[LudicrousGibs Cleanup on aisle seven!]]
* LensmanArmsRace:
** Between XCOM and the aliens. At the beginning of the game, XCOM has ballistic weapons, mostly ineffective armor, and little else, while the aliens field the much weaker Sectoids and Thin Men, armed with plasma pistols and light plasma rifles at worst. By the time XCOM has started to field advanced equipment in the form of laser weapons and armor forged from the alien alloys, the aliens up the ante with Mutons and Floaters, some armed with full-sized Plasma Rifles. When XCOM finally gets to highly advanced equipment like plasma weapons of their own, incredibly advanced armor and psionics, the aliens are fielding Elite Mutons, Heavy Floaters, Sectopods, and Heavy Plasma cannons.
** This also takes place between XCOM and EXALT in ''Enemy Within'', as both sides gradually advance from ballistics to more advanced weaponry. EXALT ''also'' gains the ability to gene modify their operatives, just like XCOM. They don't get a MEC equivalent, but they do have their own unique gene mods that are beyond XCOM's ethical limits.
* LesCollaborateurs: EXALT in ''Enemy Within''. They're a pro-alien faction that opposes XCOM, and even though they're not in direct contact with any of the aliens, still seek to make things easier for them.
* [[LethalJokeCharacter Lethal Joke Continent]]: South America's "[[WeHaveWaysOfMakingYouTalk We Have Ways]]" bonus is kind of laughable in regular gameplay, because once you get plenty of scientists you'll be completing autopsies and interrogations in a single day. But turn on the "Marathon" option in ''Second Wave'', and suddenly South America's bonus becomes ''critical'', because all research times are increased several times over, and you can't afford to waste most of a month on autopsies and interrogations. Not to mention that the research credits from interrogations greatly reduce the lengthy research times on advanced technology, which is the difference between spending an entire month unlocking a new technology and only a dozen days working on it.
* LevelsTakeFlight: The Battleship at the end of the ''Slingshot'' DLC and [[spoiler: the Temple Ship]] involve you attacking them while they're still in-flight. Despite being able to see the Earth sprawling below you, you're not at risk of falling.
* LightningBruiser:
** The Assault class is the only class that can dash/move twice and still shoot before the enemy has their turn, complete with numerous perks that significantly increase either their damage output or durability. They even get bonus hitpoints for wearing heavier armor, on top of having the best base health progression.
** A properly built Support trooper can be this as well, getting extra movement spaces that let them get to a wounded teammate or get within lethal range in less turns and gaining a second equipment slot (at Major rank prior to ''Enemy Within''), allowing them to bulk up and carry a Nano-fiber vest or Chitin plating in addition to Medikits or other gear, which makes them even tougher. The other way they can be built turns them into {{Stone Wall}}s - granting them extra uses of their smoke grenades and suppressive fire, keeping the aliens pinned down while the other team members flank the enemy.
** MEC Troopers are pretty quick on their feet if the "Kinetic Strike Module" Tactical Subsystem is chosen and/or the "Advanced Servomotor" Foundry Project is completed. They also have guns that hit even harder than a Heavy's and have a massive health pool due to their suits, as well as a number of skills/upgrades that reduce damage.
* LimitedLoadout: Every one of your troops gets a primary weapon (the type of which is determined by their class), a secondary weapon (a pistol unless they're a Heavy, in which case they get a rocket launcher instead) and a slot for extra utility items like Medikits or the Arc Thrower. Supports can unlock an extra utility slot once they reach Major prior to ''Enemy Within'', which instead has a Foundry project called "Tactical Rigging" that affects all classes.
* LoadBearingBoss: [[spoiler: Killing the Uber-Ethereal in the final mission causes the Temple Ship to begin self-destructing from the resulting release of psionic energy and the damage caused by the alien orb going out of control, necessitating the Volunteer's HeroicSacrifice to prevent it from taking the Earth with it.]]
* LockAndLoadMontage: The introduction cutscene features this.
* LostForever: Certain aliens from early on in the game usually stop showing up after a few months, which can be problematic (though it won't render the game {{Unwinnable}}) if you haven't managed to capture them for interrogation. If you're lucky, though, they may occasionally pop up during Council missions or even regular ones. Hopefully, you've brought along an Arc Thrower.
** Slightly cushioned in Enemy Within, as the later game Mechtoids now appear with one or two Sectoids in tow. Other enemies still fall under this though.
* MacGuffinDeliveryService: [[spoiler: How the aliens view the attack with your best psionic soldier on their Temple Ship. But since they still shoot on sight and never bother with any plan to get that soldier to join them, you will probably make them regret it. Alternatively: The Aliens wanted your best to be on that ship. Why? Its a test. Everything has been a test. This is the last to see if humanity has what it takes. To do what is left ambiguous.]]
* MadeOfIron:
** One of the Assault's tricks. They gain the "Extra Conditioning" passive ability once they reach Major, which confers additional health depending on their armour. Give them Titan Armor and Chryssalid Chitin, and they can soak up more damage than Cyberdisks and Berserkers. Upon reaching the Colonel rank, they can also get the "Resilience" ability, which makes them immune to {{Critical Hit}}s.
** Heavies have the "Will To Survive" passive ability once they reach Major, which reduces all damage they take by 2 points while in any kind of cover, as long as they're not flanked.
** EXALT's Elite Heavies have the "Iron Skin" gene mod, which reduces ''all'' incoming damage by 25%. [[{{Subverted}} Good thing they only have 10 Health]].
** Sectopods in ''Enemy Within'', thanks to the new "Reinforced Armor" passive ability that ''halves'' all incoming damage.
* MadScientist: Downplayed: Dr. Vahlen, the head of Research, is definitely a lot more gung-ho about [[ForScience SCIENCE!]] than [[TheProfessor Dr. Shen]], though she does persist on [[TortureTechnician personally overseeing]] [[BewareTheNiceOnes any interrogation attempts]].
* MajorlyAwesome: Any soldier who makes it to Major, the second highest rank available, is certainly awesome.
* MassHypnosis: [[spoiler: In ''Enemy Within'', the aliens forcibly mind control quite a few XCOM personnel into sabotaging internal security as the precursor to their assault on XCOM HQ. Bradford [[TookALevelInBadass is forced to beat the crap out of]] a mind-controlled XCOM technician trying to assassinate him.]]
* MauveShirt: Any Squaddie (any operative with a couple of missions or a kill under their belt, at least until you get the upgrade that gives the rank for free) is one. The customization of the troops grinds it in.
** Moreso when they reach Sergeant, which is when your battle-hardened troopers earn themselves a custom, randomly-generated nickname (that you can then customize yourself, if you wish).
** Even the highest ranking of your soldiers can qualify as Mauve Shirts. All it takes is a couple of well placed shots, a single Chryssalid or Muton Berserker, or an Ethereal [[GrandTheftMe mind controlling one of your finest soldiers into shooting their buddies]] and even your most trusted and powerful soldiers can die. Made worse on [[FinalDeathMode Ironman mode]], wherein you can't reload your saves [[KilledOffForReal and those guys are gone for good.]]
* MeaningfulName: The Slingshot DLC mission pack is so named because it throws you into tougher-than-normal missions with ''substantial'' rewards that allow you to research and build way more than you normally would be able to. Thus a little extra effort allows you to "slingshot" up the tech tree.
* MechaMooks: Played with: the Drones are definitely these. They are numerous and die in one hit, but have the ability to [[ShootTheMedicFirst repair their bigger brethren]]. The Cyberdiscs and Sectopods, however, are vastly more dangerous, as they are bristling with firepower and very heavily armored.
* TheMenInBlack:
** The Thin Men, directly drawn from the eponymous rumors started in the 1950s about mysterious agents covering up UFO sightings. They're humanoid infiltrators with extreme agility and the ability to spray poison from a distance. It's strongly implied in the autopsy report that they are in fact genetically-altered Snakemen, or at least reptilian in origin.
** The Council representative is also a mysterious MIB, though at least he's on your side.
** XCOM is technically composed of [=MIBs=], though obviously much more militant and less concerned with remaining secret.
** EXALT troops look more like traditional [=MIBs=], especially with their suits.
* MightyGlacier:
** The Heavy class packs some of the most powerful infantry weapons available to XCOM [[labelnote:*]][=LMGs=] and a rocket launcher, the former can be [[MoreDakka fired twice in the same turn]] if Bullet Swarm is taken[[/labelnote]] and are quite tough. However, they only have average movement speed and range, and cannot fire their rocket launcher after doing nearly anything.
** On the Alien's side is the Sectopod. Like the Heavy, it can move a limited distance, but it favors standing still due to being able to [[MoreDakka fire twice in a single turn]] ([[TheComputerIsACheatingBastard which sets it up for a free overwatch as well]]). Additionally, it often doesn't ''need'' to move at all, as it has a permanent cover bonus midway between half and full-cover, near-immunity to crits, and a massive health pool.
** MEC troopers in ''Enemy Within'' are bigger, stronger and more resilient than regular soldiers (and most aliens), but until you upgrade their leg servos they have similar limitations to the Heavy.
* MileLongShip: The alien battleships are enormous during raids on crashed battleships, their upper decks alone take up the whole map. A cutscene in the ''Operation Slingshot DLC'' shows a battleship hovering over a city, dwarfing the skyscrapers.
** The [[spoiler:Temple Ship]] is even bigger its emergence over the Atlantic Ocean causes worldwide earthquakes, and [[spoiler: in the final mission, its self-destruct sequence threatens the entire planet.]]
* MindRape: The psionic aliens have the full range of [[SarcasmMode fun]] [[HeroicBSOD little]] [[MindManipulation tricks]] from the original, as well as [[GoddamnedBats new]] [[PsychicAssistedSuicide ones]]. Unfortunately for them, [[HoistByTheirOwnPetard two can play at that game.]] [[spoiler: Which is exactly what the Ethereals want...]]
* MiniMecha:
** The aliens have the Sectopod in the base game, joined by the brand new Mechtoid in ''Enemy Within''.
** XCOM gets the Mechanized Exoskeletal Cybersuits in ''Enemy Within'', which require their operators to be {{Cyborg}}s.
* {{Mondegreen}}: It's "Med'''i'''kits", not "Medkits". This is a remarkably common mistake.
* MoneyForNothing: Once you manage to get satellites over the majority of the funding nations, you will be rolling in Credits. The bottleneck then becomes Alien Alloys, Elerium and Weapon Fragments, all of which need to be taken from the aliens.
* MontyHaul:
** Completing the ''Slingshot'' {{DLC}} nets you [[spoiler: an intact alien battleship]] possibly less than two months into the game, which yields a tremendous amounts of alloys and Elerium, plus an earlier route to endgame weapons. Chances are, you'll have to try extra hard to even come close to running out of resources again. On the other hand, you'll be facing [[spoiler:said Battleship]]'s guards, albeit toned down. Fighting Mutons and Chryssalids with only Ballistic or Laser weapons, Kevlar or Alloy armor, and a small team of somewhat inexperienced troops can make it all into a sequence of {{Brutal Bonus Level}}s, even on easier difficulties, though still worth the huge payout.
** ''Operation Progeny'' plays it straight for its final mission. You get 3 Lieutenant-ranked soldiers who are guaranteed to be psychic for a mission that was easier than the previous one.
* MoraleMechanic:
** Soldiers with low Will scores are more prone to panicking, which can happen if the squad takes casualties or a Muton successfully intimidates them. Panicked soldiers will shoot at a random target ([[UnfriendlyFire even their own teammates]]), run to a random and potentially dangerous location or hunker down. Regardless of which effect occurs, they cannot move or act during the next turn unless the debuff is removed with the "Psi-Inspiration" ability. ''Enemy Within'' also reduces their Aim while Panicked. However, stories abound of this backfiring; as panicked agents sometimes [[OneShotKill paste]] the enemy who frightened them.
** An Officer Training School ability added in ''Enemy Within'' is "[[AFatherToHisMen Lead By]] [[SergeantRock Example]]", which raises all soldiers' Will scores to that of the squad leader's when they're in close proximity to said leader, while [[HypercompetentSidekick those with higher Will scores aren't affected]].
* MoreDakka:
** [=LMGs=] in general, especially when using the Heavy's "Suppression" ability. Assault Rifles in general also spam rounds with the Support's "Rifle Suppression" ability, even if they normally only fire a few rounds when shooting normally. [=SHIVs=] (and MEC Troopers in ''Enemy Within'') also start off with a bullet spewing [[GatlingGood minigun]].
** The Assault's "Rapid Fire" ability (activate to fire twice with an accuracy cost), the Support's "Covering Fire" (reaction fire to enemy attacks within their sight in addition to movement) and "Sentinel" passives (fires twice on Overwatch), the Heavy's "Bullet Swarm" passive (can fire twice if they did not move that turn) and the Sniper's "In The Zone" (killing a target out of cover or flanked doesn't cost an action) and "Double Tap" (firing or using firing abilities doesn't end their turn) passives all provide you much potential for additional dakka. ''Enemy Within'' also adds the "Overdrive" passive ability for MEC Troopers, allowing them to shoot twice if they don't move, much like "Bullet Swarm".
* MultiArmedAndDangerous: Ethereals have four arms now, though unlike other examples, this is probably more for RuleOfCool than anything else, since they attack only with psychic powers and don't even carry a weapon.
* MultinationalTeam: Much more diverse than in the original game; you can even get recruits from countries that aren't part of the Council of Nations. It's not at all uncommon to have an entire six-person squad whose members are all from different countries. However, they all share the same pool of [[NotEvenBotheringWithTheAccent American accents]], which thankfully is (mostly) rectified with the ''Enemy Within'' expansion.
** In an odd twist, recruits from Scotland and recruits from the rest of the UK are treated as being from different countries, with their own flags and name pools, which might turn into FunnyAneurysmMoment given the Scottish Independence Referendum has been announced for 2014 and the game is set in 2015. (However, abductions in Scottish cities are listed as being in the UK.)
** Encouraged in ''Enemy Within'', as there's a medal type that gives bonuses based off how many different countries are represented in that soldier's squad.
* MutualDisadvantage: It is possible to place a soldier in a position which has them flanking an enemy (negating their cover bonus and significantly increasing their chance of scoring a CriticalHit) whilst simultaneously having them be flanked by that enemy. Risky, but sometimes worth it.
** This is the Assault class' specialty, since their basic "Run & Gun" ability allows them to shoot after moving twice/dashing, allowing them to jump right behind the cover the aliens are in and pumping them full of buckshot/lasers/alloy shards in the same turn before they can act. They can also have the "Lightning Reflexes" ability, which forces the first reaction shot fired at them in a turn to miss.
* MyRulesAreNotYourRules:
** Aliens (and EXALT soldiers in ''Enemy Within'') don't give a flying rat's ass about their comrades and will never panic unless psychically induced (or set on fire with the MEC Trooper's Flamethrower in ''Enemy Within'').
** Robots are immune to psi-powers, so [[TacticalRockPaperScissors it's good tactics to send your S.H.I.V.s against psi-users]]. However, Ethereals can use their unique "Psionic Lance" and "Rift" psychic powers, which do increased damage the lower the target's Will is. Since robots have 0 Will, these psychic abilities can [[OneHitKill one-hit kill any of your S.H.I.V.s]].
* MysteriousWaif: An optional subplot of ''Enemy Within'' follows Annette Durand, an unusual, psionically gifted individual with a mysterious past. The aliens considered her such a threat that they were willing to strafe a dam while the truck carrying her was crossing it, and then send ground troops onto the stricken structure to keep XCOM from rescuing her.
* MythologyGag: With a side of GeniusBonus.
** The Council of Nations is represented by a bald man wearing a suit sitting in the shadows. In the original game, the Funding screen and the end-of-month summary was displayed on a background with a very similar man holding a briefcase full of money.
** [[http://www.2kgames.com/blog/xcom-enemy-unknown-release-date-special-edition-and-more The pre-order bonus]] and the ''[[{{DLC}} Elite Soldier Pack]]'' includes a blonde dude with a humongous flat-top, as well as a [[VideoGame/TeamFortress2 TF2]] Hat depicting the same hairstyle. In the original game, all X-COM soldiers had this same haircut.
** The basic weapon for Interceptors are Avalanche Missiles, which were the best terrestrial interceptor weapons available in the original game.
** Manufacturing your first laser or plasma rifles has a cutscene where they're used on cardboard cutouts of the original Sectoids (for lasers) and Mutons (for plasma).
** The Thin Men are ''very strongly'' implied to be genetically-altered Snakemen. Even better, the original game implied that the Snakemen had a very dangerous and deadly poison, though it never made it into the game. One of the Thin Men's most dangerous attacks is hitting you with a cloud of deadly poison.
** The Floater Autopsy report is codenamed "Crimson Cape", a reference to these aliens' appearance in the original.
** The final mission is always named "Operation Avenger". In the original, the Avenger was the transport ship X-Com had to build to reach the final mission on Mars.
** The Elerium research project is codenamed "Project E-115", a reference to the original game where Elerium was referred to as the 115th element on the periodic table [[labelnote:*]]This element, which only exists theoretically, is currently known under the provisional name [[http://en.wikipedia.org/wiki/Ununpentium Ununpentium]], but like with all transuranic elements, the first research team to successfully produce it will be allowed to name it. It might be not too late to push for Elerium.[[/labelnote]]
** The short musical cue that plays when a round of psi training is completed is from the original's Geoscape theme.
** The Achievement for building your first Firestorm is called "Ride the Lightning", which might refer to the much-maligned aircraft of the same name from the original.
** Muton Elites and Berserkers are red, just like "Mr. Angry Red Suit" who was never fought in the original.
** An arcade machine in the base's recreation room has the original game running.
** Leaving the game overview in the Situation Room screen has Bradford spout off some idle chatter every so often... with some subtle references to the original game.
-->'''Bradford:''' ''"This is Central, I'm receiving you...what do you mean you think you saw a snake? What the hell does that have to do with anything?"''
** In ''Enemy Within's'' "Site Recon" Council Mission, Bradford remarks that at least the grounded ship [[spoiler: the Chryssalids are spawning from]] wasn't a cruise liner. ''Terror From the Deep'' had [[MarathonLevel very long]] cruise ship Terror missions, which were generally very stressful and tended to result in extreme death rates.
** One of the UFO Retrieval Maps added in ''Enemy Within'' is modeled after the classic 1994 X-COM farmhouse terrain, complete with barn.
** Zooming way in (usually during a cinematic action shot) in the "video rental store" part of one map will show a mohawk-wearing X-COM soldier from the original game, wearing that game's version of the Alloy Armor with cheekbone-helmet.
* {{Nanomachines}}: Meld, cybernetic nanobots with both organic and mechanical components. They operate by allowing unprecedented synergy between organic tissue and mechanical parts (or between two incompatible organic tissues) down to the cellular level.
* {{Nerf}}:
** Blaster Launchers were downgraded from insanely powerful programmable guided missile launchers to merely flawlessly accurate and harder-hitting smart rocket launchers.
** Chryssalids as compared to the original, though they're certainly still dangerous. They no longer instantly zombify your units [[labelnote:*]]they have to ''kill'' that unit first via melee damage, which can be reduced by your units wearing armor made from [[HoistByHisOwnPetard Chryssalid chitin]][[/labelnote]], and the zombies no longer need to be [[KillItWithFire killed with fire]] to prevent a new Chryssalid from hatching (they can be killed within three turns with anything). Furthermore, Assaults can learn a special ability that gives them Reaction Fire against enemies that close in on them, useful against the melee-only Chryssalids.
** ''Enemy Within'' [[ObviousRulePatch nerfs the near-game-breaking power of "Squad Sight"]], while actually ''buffing'' several skills that proved to be rarely chosen, like "Covering Fire", "Up Close and Personal" and "Snap Shot".
** Also from ''Enemy Within'', instead of guaranteeing critical hits, Ghost Armor's cloak now only gives a 30% chance increase, while the cloaks from the invisibility grenade [[ObviousRulePatch don't offer any crit bonuses]]. Additionally, Heavies' "HEAT Ammo" ability only gives a 50% damage bonus against robotic units, compared to the 100% from the original.
** Science got nerfed too; it takes a lot longer to research beam weapons and carapace armor, for one, so you are encouraged to capture more aliens alive and cut the research time for those in half. You are similarly encouraged to try to get more scientists and/or build laboratories, where in ''Enemy Unknown'' you could safely focus on getting engineers and nothing else.
* NeverMyFault: PlayedForLaughs in a news blurb for a low-panic United Kingdom, where a famous footballer who missed the winning shot claimed he was "blinded" by UFO lights during his match.
* NeverSplitTheParty: Letting a Squadsight Sniper hang back all alone or sending a lone soldier to flank some enemies worked in the vanilla game, but not anymore. ''Enemy Within'' {{invoke|dTrope}}s this trope with the Seekers, which latch onto isolated soldiers and will strangle them to death if another soldier doesn't rescue them in time.
* NewGamePlus: ''Second Wave'' mode. Initially only available via mods, it was officially added to the game in the January 7, 2013 patch for PC, while consoles got it as free {{DLC}}.
* NiceHat: The ''Slingshot'' {{DLC}} adds about a dozen new hair/helmet options, amongst which is a beret. There's also a beret-and-shades combo, for added {{Badass}}itude.
* NicknamingTheEnemy: Aliens in general are usually called [=ETs=] or X-rays during combat[[labelnote:*]]the "X-Ray" naming is part of the long-standing US military "theme naming", where the first letter of the enemy nationality is used to come up with a nickname. So we get '''G'''ermans becoming '''G'''erries, Viet '''C'''ong becoming '''C'''harlies, and e'''x'''traterrestrials becoming '''X'''-rays[[/labelnote]]. Also, during the Autopsy cutscenes or reports, Dr. Vahlen mentions that several aliens' designations were originally nicknames the troopers came up with that stuck.
* NintendoHard: Classic and Impossible. For bonus points, Classic (or Impossible) and [[FinalDeathMode Ironman mode]]. And if that weren't enough, players can make the game even ''harder'' with the ''Second Wave'' options[[note]]Including, but not limited to: increasing the damage range of all weapons by 1 (ballistic, lower end only) or 2 (laser and plasma, lower and upper end), randomizing rookie starting stats, randomizing soldier level up stats (which can produce things like an Assault who can snipe with a shotgun and a Sniper who can't hit the broad side of a barn), requiring a live capture to unlock psionics, and significantly increasing the time requirement for research and development (from days to weeks, even ''months'' in some extreme cases).[[/note]]
* NoOneGetsLeftBehind: PlayedStraight by a Support class perk, which allows them to revive critically wounded allies (albeit with minimal health and a long time in sickbay after the mission). Can also be cruelly {{Subverted|Trope}}, however, by choosing to abort a mission; doing so results in any soldiers near the Skyranger boarding ''[[VideoGameCrueltyPotential and leaving everyone else to die.]]''
* NoFairCheating: Turning one of your squad into a HeroUnit will disable achievements for that particular campaign.
* NoHoldsBarredBeatdown: When a Berserker manages to score a killing blow. The poor soldier is gut-''stabbed'' and then hammer-fisted into the ground as they double over, and then the alien continues to savagely beat them for a few more seconds.
** In ''Enemy Within,'' MEC troopers can get in on the action if they choose the Kinetic Strike Module on their MEC suit. There is even a special animation when used to kill Mechtoids, and this trope is definitely involved.
** The animation used when killing a Berserker with a MEC rocket-punch is especially awesome the Berserker initially goes for this trope, but finds out it's facing a physically stronger enemy for the first time...
* NonLethalWarfare: The Arc Thrower is your primary tool for capturing aliens. While useful for taking down aliens for interrogation, it's also essential for seizing any piece of handheld alien technology, which otherwise self-destructs upon the wielder's death. It also remains a useful tool throughout the mid-to-late game, as it's a lot cheaper - though much, ''much'' riskier - to stun aliens and jack their gear than assembling it yourself out of precious alloys and Elerium.
* NoRangeLikePointBlankRange: The Assault class encourages this, especially in ''Enemy Within''. Combining "Close and Personal" with "Rapid Fire" allows your soldier to run up to an alien, shoot them without losing an action, and then use "Rapid Fire" to shoot them twice more. If it's a Berserker and your soldier has "Close Quarters Specialist," they can get off ''four'' shots in one turn if either the Berserker is drawn into the required range by another soldier or if they pull back slightly with "Run & Gun" before using "Rapid Fire".
* NoSell:
** Titan Armor, for fire and poison. In ''Enemy Within'', strangulation as well, and Ghost and Archangel Armor also gain the same immunities.
** Medikits provide immunity to poison.
** In ''Enemy Within'', Respirator Implants for poison and strangulation. The Chitin Plating and Mind Shield items, as well as the "Bioelectric Skin" gene mod, grant immunity to strangulation.
** A missed psychic attack goes like this. The dramatic camera moves to focus on the attacker, pans over to the target as the attacker releases psionic energy, and... the target doesn't react at all, and the interface informs you the attack failed.
** Purely visual, but some of the miss animations have the shots hitting, but failing to penetrate the target's armor.
** Major-ranked Heavies can NoSell weak attacks, like those of Sectoids and Drones, if they're in cover and not flanked. Additionally, Colonel-ranked Assaults can NoSell critical hits.
** Once EXALT Elite Medics activate their "Regen Pheromones", they become immune to explosives. One of the achievements involves killing Medics with explosives before they can NoSell them.
* NothingIsScarier: On some missions, either because of a larger than usual map or placement of enemies, it can take you a while to actually find the aliens if you're advancing slowly. This only makes you more nervous as you continue to worry about stumbling into a horde of Mutons or a swarm of Thin Men.
** Or worse, when you've moved forward so quickly that you wind up with aliens behind you - but you aren't sure where they are, and you're standing in the middle of an alien base with Mutons and Chryssalids coming from god-knows-where. You have two options - split the party, or wander around hunting for the last enemies on the map.
*** Or pull a six-way BackToBackBadasses LastStand, because twenty turns in, the aliens have their fog of war removed so you don't wind up chasing the last alien all over the map. Bonus points if they all make it out alive.
* NomDeGuerre: Bradford's is "Central", the Skyranger is "Big Sky" and your squad is "Strike-One". Also, any soldier that makes it to Sergeant earns one, though the player can change it to whatever they prefer. They're randomly assigned, though each class has their own list of available nicknames.
* NonStandardGameOver:
** If you fail the very first tactical mission by losing all four of your initial rookies, you don't get the option to return to base. The Council of Nations immediately decides that the XCOM project is a failure and shuts it down. You do get the option of restarting the mission, though.
** In ''Enemy Within'', failing the [[spoiler: XCOM Base Defense mission]] causes a game over, for obvious reasons.
* NotEvenBotheringWithTheAccent:
** Your soldiers are [[MultinationalTeam recruited from all over the world]], but they all speak perfect American English. Adding unique accents for every single member nation would probably be overkill for the developers, of course, which is why they went with this instead (see WeAllLiveInAmerica below).
*** In ''Enemy Within'', this has been changed; you can customize your troops to speak in one of seven[[note]]English, French, German, Spanish, Italian, Russian, and Polish[[/note]] languages, whether it's their country's native tongue or otherwise.
** No matter where EXALT's main base is located, [[WeAllLiveInAmerica the voice over for the ending cutscene is still an American-accented man referring to a radio/news station with an American naming pattern.]]
** Dr Vahlen is supposed to be a [[HerrDoktor German scientist]] and usually speaks in a GratuitousGerman accent, [[OohMeAccentsSlipping but half of the time]], she changes to overly enunciated [[BritishAccents RP]]. Apparently, her character had originally been meant to be British.
* NoTranshumanismAllowed: Doctor Shen has shades of this on Psi abilities. Then again, it's completely new territory and the only other users/examples are the invading aliens, so his hesitation is understandable. [[spoiler:He's proven wrong, as the strongest human Psi user ever, The Volunteer, pulls a HeroicSacrifice to save the Earth.]]
** He also questions if something as cybernetically enhanced as the Floaters can even be considered a true lifeform anymore, saying "if that is humanity's future, I want no part of it." [[spoiler: The Uber-Ethereal reveals in the final mission that the Floaters were a failed project to create a resilient psionic species, and decided to rip out their organic parts to make them better weapons for the Ethereals' purposes.]]
** [[AvertedTrope Averted]] in ''Enemy Within'', as soldiers can now be enhanced with BioAugmentation and [[{{Cyborg}} Cybernetics]]. The expansion even changes Shen's voice line instead of saying "I want no part of it", he expresses determination to proceed with cybernetic modification, albeit without sacrificing the MEC troopers' humanity. However, EXALT's bio-augmentations are taken to a level [[EveryoneHasStandards even Vahlen refuses to go]].
* NotUsingTheZWord: Averted, though lampshaded: Dr. Vahlen can't believe she's using the word "Zombie". You can ''lean'' on her hesitance.
-->Dr. Vahlen: ''"As unprofessional as it sounds, it appears the bite seems to have turned him into a ... zombie."''
* OhCrap:
** When things start to go against you in battles, your soldiers can freak out, panicking and losing their turn. The lower the soldier's Will score, the more likely they'll panic when another soldier dies or is mind-controlled, when they take a hit, or when a Muton calls them out with their Intimidate ability. When they panic, they can shoot a random target (with an Aim penalty and randomly chosen from your other troopers, visible aliens and civilians), run for cover, hunker down or just run in general.
*** Aliens (and EXALT soldiers in ''Enemy Within'') can be forcibly panicked by Psi-Panic (and MEC Flamethrowers in ''Enemy Within''), and will act much the same way as a panicking XCOM soldier. They will not do so normally, however, though they will temporarily retreat and/or call for help if you quickly kill enough of them.
** In a metagame sense, you'll be saying this a lot when you encounter a new alien unit and they unleash an ability you haven't seen before. Additionally, every time you see Chryssalids (early-mid game) and Sectopods (all the time, especially if there's more than one).
*** You'll be saying it an awful lot when you send a trooper into a room to take cover and clear up the fog of war when raiding a landed or crashed UFO...and then it turns out he's running into the middle of a group of Mutons.
** One of the most common reasons for this is on your orders for the last soldier who hasn't acted yet. Dash forward without caution, and you might encounter a group of Chryssalids or a Berserker, who use their "enemy spotted" action to get as close to your troops as possible... then it's their actual turn to act.
* OldSchoolDogfight: Battles between [=UFOs=] and your interceptors are pretty straightforward aerial shoot-outs. While your initial aerial weapon are the Avalanche missiles, you can later develop and equip various cannons, which may force your interceptor to close in to dogfighting range. Crafting various modules in your base allows your interceptors one-time bonuses to Aim, Dodge, and Chase.
* OmnidisciplinaryScientist: Dr. Vahlen and every scientist in the labs. They are all equally versed in biology and physics, everything short of engineering (which is the domain of the engineers, who are themselves downplayed examples as they can work into anything that fits under the umbrella of "engineering"). Which is presumably why they were hired in the first place.
** Averted, just once, in a cutscene where Dr. Vahlen is trying to explain what the Outsider Crystal does. She's at a loss for words but then Dr. Shen steps in and says, "perhaps this is outside your field of expertise."[[spoiler: (It is an ''antenna''.)]]
* TheOmniscientCouncilOfVagueness: The Council, of course, complete with a mysterious man with his face framed in shadow who signs off by saying:
-->''"We... will be watching."''
** And although their entire style and word choice fulfills every ConspiracyTheorist's nightmare, they are in effect {{Reasonable Authority Figure}}s who only complain if you slack off against the aliens. If you do exceptionally well (A rating), they even point out that they're extremely impressed and didn't expect the project to do so well, so keep up the good work.
* OneBulletClips: Another change from the original games, ammunition is no longer tracked as separate items and soldiers can reload at will.
* OneManArmy: There's an achievement for clearing a UFO crash site with just one soldier[[labelnote:*]]Specifically, you have to do it on Classic or Impossible, which only makes it worse[[/labelnote]]. It's pretty tricky ''even with'' superior equipment and tactics, and you definitely shouldn't try it with a rookie soldier.
* OneSizeFitsAll: All the suits of armor you manufacture can be worn by any of your soldiers. If you unequip an armor to put it on another soldier, the armor will instantly adapt to the sex, body build and class of its new owner. This is especially noticeable because the armors are rendered differently on screen depending on those parameters.
* OneStatToRuleThemAll: Aim. Your soldiers' primary weapons are the main damage dealers in the game and will be the weapons you use most often. Explosives destroy alien corpes when they kill and psyonics are more of a supporting ability than a damage dealer. Since XCOM is largely a game of rocket tag, a single miss could allow an alien to flank your team, or when faced with a [[BossInMooksClothing Sectopod]], allow it to completely wreck them.
* OneWorldOrder: Despite the ominous tones, the Council of Nations is a subversion. They're essentially a UN-expy of the world's leading countries who function more like TheAlliance than anything else. Do poorly however, and your actions might splinter the Council apart as nations drop funding to fend for themselves.
* OnlyAFleshWound: Weapons fire can count as missing even when it visually hits the target. Because the game rolled "failed" or if it's suppression (which doesn't do damage unless a Colonel rank Heavy-specific perk is chosen), the representation just generates fire in a random cone, which means even missed shots could drill the target right between their eyes. Of course, those shots don't do any damage, even if your barrage of suppressive fire hits that Muton in the face.
* OnlySixHelmets: The {{DLC}}s add helmets to the soldier customization menu, a grand total of 9. It's incredibly obvious that certain helmets are designed to go with certain armor sets. Not as bad as other examples, because there's enough variety that every member of your squad could have a unique helmet, and the color customization can make even the same helmets look distinct.
* OOCIsSeriousBusiness: The Council is almost impossible to upset. He only expresses concern when several council members withdraw and even if you mess up a few times over the month he's still confident that you'll improve. But when you [[GameOver lose 8 council members]] he'll call you up and tell you that the XCOM project was a stupid idea to begin with that would never succeed. [[spoiler: It turns out he's being mind controlled when he says that, and there's nothing you can do to stop him from shutting down XCOM.]]
* OperationBlank:
** Every XCOM ground mission gets a two-element codename (e.g. "Operation Defiant Empire"). Most are random, but story missions and special council missions tend to have {{Meaningful Name}}s. Non-story missions may, however, end up with {{Word Salad Title}}s.
** Each research project has a codename (e.g. "Mobius"), which is unique to each project.
* OurWeaponsWillBeBoxyInTheFuture: Most pronounced with lasers. [[JustifiedTrope Justified]] in that they are designed and manufactured on short notice to create a useful weapon, not win a design contest. The plasma weapons are decidedly ''not'' boxy, but rather rounded and (in some cases) cylindrical, but they're copied from the alien designs rather than designed from the ground up. The Arc Thrower is essentially a cube sitting on top of a pistol grip.
** Also, going by the concept art and various in-game animations, [[http://img.gawkerassets.com/img/1833827d4wo89jpg/original.jpg they have a 'fold in' mode of sorts]], so the boxy-ness is something of a design requirement.
** EXALT weapons avert this, as their engineers took their existing gun frames and stuck the laser parts on.
* OutrunTheFireball: Once in the vanilla game, and again in ''Enemy Within'':
** During the game's conclusion, there's a double instance: [[spoiler: The Volunteer is trying to get the Temple Ship into an orbit that won't destroy the world (running the fireball away from the target), while the remaining XCOM soldiers rush back to the Skyranger to escape the soon-to-be-debris Temple Ship.]]
** In ''Enemy Within'', during the "Site Recon" Council mission, an airstrike will be called in (for very good reasons). You then have a limited number of turns to get your squad to the evac point: if you don't, they ''will'' be blown up by the resulting detonation. [[spoiler: The loss of an XCOM squad isn't much compared to the possibility of a Chryssalid apocalypse.]]
* OutsideTheBoxTactic:
** Overwatch and Suppression can virtually lock a unit into place, letting aliens scuttle about to flank the poor soldier... what's this, [[GrapplingHookPistol the soldier is grappling away without a single reaction shot?]] Yep, apparently, nobody is paid enough to shoot a target moving that fast.
** Multiplayer-only, a Chryssalid killing a Sectoid who's Mind Merged with a human will zombify that human after the backlash kills them, pretty much giving you another Chryssalid free.
* PaletteSwap: EXALT weapons have the exact same stats as their XCOM counterparts. The in-game descriptions hang a minor lampshade on how unlikely the similarity is.
* PaperThinDisguise: Thin Men are only nominally human-looking. Their proportions put them right in the UncannyValley, they've got reptilian eyes under their sunglasses and they've got green scales showing right around the collar line on their necks, like their human makeup is wearing off. They never fool your XCOM team. Openly carrying light plasma rifles and attacking the XCOM team on sight doesn't help either. But, you'll encounter ''only'' Thin Men in some of the Council missions, so their disguise may work on the civilian population.
* PeopleJars: Genetically modifying a soldier requires them to step into a huge jar of Meld for 3 days per added gene mod. They're just fine once emerging, however.
* PinnedDown: The "Suppression" ability available to Heavies, Supports, and some aliens. It penalizes the target's accuracy and allows the suppressor to take a free reaction shot if the target moves.
* PlasmaCannon: In various forms, this is the standard-issue weapon for the aliens, and the best (and most expensive) weapons available to XCOM.
* PoisonousPerson:
** The Thin Men: they're highly toxic and can spit poison clouds at your group. They also create a poison cloud when they die.
** Chryssalids can poison those who manage to survive their melee strikes.
* PokeInTheThirdEye: You can gain a gene mod to produce a mental feedback that badly damages any enemy attempting a psychic attack. The damage occurs even if the attack succeeds, so if a wounded alien mind-controls an agent with this trait, it might prove to be a rather SHORT bout of control...
* PointOfNoReturn
** In the vanilla game, it's '''Merciful'''. The game warns you that the final step towards attacking the final ship will stop all progress anywhere else.
** In ''Enemy Within'', '''Nasty'''. [[spoiler: [[AllYourBaseAreBelongToUs The aliens assault your headquarters]] a few weeks after the Alien Base Assault, and it's always a group of your highest-ranking soldiers that you control in the defense]]. However, the expansion came with a helpful button that lets you unequip all the gear of those not in your currently selected squad. If you use it often and are not currently leveling your heavy-hitters, this will [[spoiler: result in your best troopers fighting off Cyberdisks and Berserkers with basic weapons and armor]]. Hopefully you kept your saves up to date.
* PostMortemOneLiner: All unit voices come with some remarks following a successful kill:
-->''"He's out of the game."''
-->''"Kill confirmed."''
-->''"Dead and gone."''
* PoweredArmor: The Titan Armor, which comes with immunity to fire and poison and grants a huge bonus to health. You also get an achievement called "Man No More" once you build one. The Archangel Armor is basically the same, but with a built-in jetpack and slightly less health.
** The MEC suits technically count as powered armor, as they are worn like regular armor by the cyborg MEC troopers. However, they're so big they move into MiniMecha territory.
* PraetorianGuard: The Muton Elites serve as this for the Ethereals. Whenever you see an Ethereal, he'll ''always'' have a Muton Elite or two as his personal guard, and any mission with an Ethereal around will involve multiple Elites as a roaming alien squad.
* PreMortemOneLiner:
** Though not stated directly to the aliens, Assault class soldiers will issue one when you activate their "Run & Gun" skill. Made even more badass if accompanied by the Ghost Armor's invisibility and wrapped up with a provided PostMortemOneLiner:
-->''"Going silent."'' [cloaking]
-->''"Moving in for the kill."''[=/=]''"Gun 'em down!"'' [Run & Gun]
** Psionic troopers can also break out a bone-chilling one, or an EvilLaugh, when using their psionic abilities:
---> ''"Your nightmare is just starting..."''
* {{Precursors}}:
** [[spoiler: The Uber Ethereal mentions "Them" who promised his kind [[AscendToAHigherPlaneOfExistence ascension]], but ultimately failed to deliver.]]
** [[spoiler: The Ethereals are AbusivePrecursors to the other alien species, having [[UpliftedAnimal uplifted]] them all to use as proxy soldiers, tools and psionic sustenance.]]
* PretentiousLatinMotto: "Vigilo, Confido" (possible translations include "[[http://www.pageofreviews.com/2012/08/vigilo-confido-translating-x-com%E2%80%99s-new-motto/ I am watchful, I am relied upon]]" and "[[TemptingFate watch, I am confident]]". "Confido" might also be interpreted as referring to secrecy.) on XCOM's logo. ''Enemy Within'' adds "Mutare Ad Custodiam" (Change to Guard) and "Bellator In Machina" (Warrior in the Machine) for its new Genetics and Cybernetics branches respectively.
* ProductionForeshadowing: News blurbs from as early as the vanilla game mention how there are quite a few alien sympathizers in the world's population, advocating peaceful acceptance of Earth's conquering. EXALT from ''Enemy Within'' is an entire faction made of these type of people.
* TheProfessor: Dr. Shen, the head of Engineering. He occasionally wonders out loud if XCOM's technology will be repurposed for war with other humans if the aliens are fought off, though he quickly decides that we can jump that hurdle when it comes.
* ProudWarriorRaceGuy: ''All'' of the Mutons. Shoot one without killing it or they gun down a XCOM soldier/unarmed civilian? The guy will likely come out of cover roaring and [[BoisterousBruiser pounding his chest like no tomorrow, taunting you]], probably scaring any rookie nearby. These guys clearly enjoy their job, and it's obvious why the Ethereals like having them as bodyguards.
* PsychicLink:
** Sectoids can use their telepathic abilities to boost the stats of their allies with an ability called Mind Merge: the target gets +10% to Aim and +1 HP for a turn. What you're not told until you figure it out for yourself is that killing the Sectoid that's boosting the other unit kills them both as a result of psychic backlash. In ''Enemy Within'', it has different effects on Mechtoids, which gain a damage-reducing shield instead. Killing the Sectoid will only remove the shield and mildly damage the Mechtoid.
** Killing an alien who has mind-controlled one of your soldiers doesn't harm the soldier, who is placed under your control again. There is a sole exception to this rule: [[spoiler:In the final mission on the Temple Ship, when you kill the Uber-Ethereal, he releases control of whatever soldier he has undoubtedly seized control of, and all of the other enemies in the room explode; including any soldiers that the other Ethereals have control of. The ending triggers immediately afterwards, with the only thing left of your soldier being a scorch mark on the ground.]]
* PsychicPowers: The Gift comes with many more abilities than the traditional mind control. Among other things, [[spoiler:Ethereals can now ''[[AttackReflector reflect your laser and plasma shots back at you]].'' Eep.]]
** You can gain them yourself, with 5 different powers available to your "gifted" soldiers: "Mindfray", a damaging attack that also debuffs the target, "Psi-Panic", a panic-inducing attack, "Psi-Inspiration", an ability that bolsters your allies' Will, "Telekinetic Field", a telekinetic defensive field, and good old "Mind Control". [[spoiler: The Volunteer gains two, the "Rift", which deals massive [=AOE=] damage, and a link to the Ethereal HiveMind.]] SidMeier has all of them.
* PureEnergy: The Outsider constructs.
* PunchedAcrossTheRoom: MEC Troopers with the "Kinetic Strike Module" in ''Enemy Within'' can do this to aliens if the blow kills them, often hard enough to send them right through a wall or cause cars to immediately explode on impact.
* [[spoiler:PyrrhicVictory]]: Narrowly averted at the end of the game. [[spoiler:As the Temple Ship is destroyed, it begins to form a black hole of sorts that could swallow the entire Earth whole. Luckily, [[HeroicSacrifice the Volunteer stays behind]] to bring the ship as far from the planet as possible before that can happen.]]
* TheQuisling:
** One of the {{Escort Mission}}s has a politician who (supposedly) is in collusion with the aliens as the escortee.
** Subverted in the game over cutscene. [[spoiler:The Council decides to join forces with the aliens, but it is then revealed that this is because they are being mind controlled.]]
** EXALT in the ''Enemy Within'' expansion is an entire faction of these, believing that the aliens will uplift humanity and take steps to sabotage XCOM's efforts to defeat them at every turn. [[spoiler: While they aren't wrong about why the aliens are here, they are actively opposing the only faction that the aliens have an interest in.]]
* RaisingTheSteaks: An unusual take. Chryssalids can implant their eggs in species besides humans, which would presumably create a zombie as well. The ones we see it demonstrated on are carcasses of sharks and large fishes, which [[ChestBurster new Chryssalids emerge from when you venture near]], [[spoiler: and they can use a whole whale as a breeding nest, which hatches a new bug each turn]]. This also explains the [[AliensStealCattle dead cows]] around Abductor ships.
* RageHelm: From the ''Slingshot'' {{DLC}}, the final helmet has [[http://cdn3.sbnation.com/entry_photo_images/7286641/2KGMKT_XCOMEU_Screenshot_DLC_Slingshot_09.jpg a head-encompassing faceplate with a skull imprint]], a la [[VideoGame/HaloReach Emile]] and [[http://farm5.staticflickr.com/4144/4969654691_e4660762d3_z.jpg his distinctive helmet]].
* RandomNumberGod: Will actually ''help'' you in the lower difficulties, but you'll still endure the full capriciousness of His/Her whims in Classic and Impossible.
* RealityEnsues:
** Sectopods can launch [[DeathFromAbove Rocket Barrages]], which can really rain explosives on your parade... unless if they [[ArtificialStupidity do so while inside]], where the missiles simply explode on the ceiling harmlessly. Keep in mind, the Sectopod will have wasted ''two'' turns doing it.
** EXALT versus XCOM. While EXALT ''does'' employ sneaky, underhanded tactics befitting a cellular terrorist group, they fall short in actual combat, which is [[GenreSavvy likely why they emphasize secrecy and avoid combat with XCOM whenever possible]]. [[CurbStompBattle In general, it goes about as well as you would expect a team of civilians-turned-terrorists going head-to-head with a squadron of hardened military veterans to go.]] This becomes even more noticeable after XCOM acquires Plasma weapons and PoweredArmor, since EXALT never [[spoiler: (except for a high priority target like Annette)]] directly engages with the aliens and therefore never acquires and reverse-engineers the tech to move past Laser weaponry and Alien Alloy armor.
* ReasonableAuthorityFigure: Funnily enough, [[TheOmniscientCouncilOfVagueness the Council of Nations]] is this. In any other game, they'd be the antagonist, but here, they provide XCOM with the funding they need to keep things running, request special missions that provide the second highest decrease in panic levels (next to successful Terror missions), and only complain if you're failing at your job to repel the alien threat.
* RedOniBlueOni: Dr Vahlen and Dr Shen. Dr Vahlen is enthused by the [[ForScience potential discoveries]] that can be gleaned from examining the aliens, while Dr Shen is concerned and disgusted by what the aliens use the tech for and whether [[HeWhoFightsMonsters humanity might wind up treading the same path]].
* RedShirt:
** Your Rookies at first. Piss poor aim, low health (and likely armor), and no special abilities mean that these unlucky guys can have an abysmal survival rate. Eventually becomes subverted as they grow in level [[TookALevelInBadass and lethality]].
** XCOM base security personnel. No matter what level or how much gear your regular squaddies have, they'll still be ranked as Rookies and carry basic ballistic weapons and frag grenades. They're only used for [[spoiler: the base defense mission]] as fodder, both due to the sheer number of enemies and the lack of choice in the soldiers and equipment you can use.
* ReedRichardsIsUseless: {{Averted}}, provided you fulfill the requests that Council Nations sometimes make. Providing Thin Man and Sectoid corpses allow for major breakthroughs in medical fields, Floater corpses enable advanced prosthetic limbs, Arc Throwers make quelling riots easier, reconstruction is hastened thanks to advanced new alloys being available, and militaries (and even civilians, in some cases) can field laser and plasma weapons, as well as advanced body armor and enhanced electronics.
* {{Retraux}}: Several character sheets of the aliens were released as promotional material and [[http://i.imgur.com/zrkeH.jpg all of them included their sprite from the original game for comparison]]. What about the Thin Man, who was widely different from the Snake Man, you might ask? [[http://i.imgur.com/Bqkog.jpg Why, the developers made an entirely new old-style sprite for him, of course]].
* RoarBeforeBeating: Floaters and Mutons.
* RocketPunch: In ''Enemy Within'', one possible upgrade to your MEC Troopers is a "Kinetic Strike Module" [[ExpospeakGag which is fancy-talk]] for a ''rocket fist'' that can punch ''Muton Berserkers'' so hard that if there's a vehicle less than a few tiles behind it, [[StuffBlowingUp the car explodes on impact]].
* RocketTagGameplay: Early-game works like this. Sectoids, Thin Men and Floaters don't have many hit points, but are armed with deadly plasma weapons that can kill or badly wound your rookies in one hit. Your rookies only have a smattering of hit points themselves, but their starting assault rifles and frag grenades are more than enough to kill the Sectoids and Thin Men in one hit (except on [[HarderThanHard Impossible]]). Later in the game, when you have better armor and the hardier alien species show up, you'd better have a good understanding of tactics and teamwork when that Muton doesn't go down in one hit.
* RuleOfCool: Pump-action ''lasers''.
* RuleOfFun: Weapons have been noticeably nerfed from their real-life effective ranges, but playing a game on the scale of hundreds of meters wouldn't be as fun. It would also be much harder to program and design.
* SacrificialLion: The German Recon team from the tutorial. Most you will find on the street, disemboweled. The last one will be [[spoiler:in the warehouse, giving CreepyMonotone shouts of "[[GratuitousGerman Hilfe]]", [[MindControl mind-controlled]] by a psionic alien. He cannot be saved and kills himself and one of your guys with a hand grenade if you come close]].
* SadisticChoice: Any time there are Abduction missions. You can only save one of the cities at a time and panic ''will'' rise on the continents you didn't deploy to. It takes some skillful juggling just to keep the panic level from going completely critical and, in the worst-case scenario, can result in having to decide which nation(s) you can afford to lose.
* SaveScumming: Just as practical and common a technique as in the original, much to the chagrin of some members of the fanbase. That said, you can't just reload a game to change the outcome: The 'seed'[[labelnote:*]]The core number the RNG uses to determine what happens[[/labelnote]] doesn't change when reloading a saved game. In layman's terms, Soldier A misses a 98% shot, he'll always miss that shot if you keep reloading from that specific save. You'll have to move another soldier, maybe have him fire, or just skip Soldier A's turn for a better probability.
** Averted in Ironman mode[[note]]Added in since it was a popular SelfImposedChallenge in the original games[[/note]], which entirely prevents this. That being said, even in Ironman, most fans consider it perfectly legal to create backups of your saves in the event of a GameBreakingBug. Even on Ironman though, the game only saves at the beginning of your turn, meaning you can still get scumming by quitting the entire game and coming back. A do-over of even one turn can be golden on higher difficulties.
** One of the new ''Second Wave'' options added to ''Enemy Within'' is explicitly called this, which removes the locked seed mentioned above, allowing a player to reload his game till he gets the desired outcome.
* SceneryGorn: Some of the new maps in ''Enemy Within'' are breathtakingly desolated. "Portent", the first map in the ''Operation Progeny'' storyline, stands out in particular.
* SciFiWritersHaveNoSenseOfScale: The No Sense Of Units variety. A news blurb mentions how the worldwide death toll numbers in the "thousands." Not hundreds of thousands, not tens of thousands, but "thousands." That number would barely take a dent out of a decently-sized city, and seems impossibly low given the large-scale destruction we see during Terror! missions. On the other hand, it could be that the official news reports are deliberately under-reporting the number of casualties to prevent panic from rising.
* ScrewThisImOutOfHere: During the "Site Recon" Council Mission in ''Enemy Within'' where you investigate a fishing village that's gone silent, your troops encounter [[spoiler:a [[ZombieApocalypse large number of Zombies and Chryssalids]]]]. About the time you discover [[spoiler:[[OhCrap the Chryssalids are using a whale carcass as a breeding ground]]]], orders come to [[DeathFromAbove call in an airstrike]]. The rest of the mission involves [[TimedMission running back to the extraction zone]] before the airstrike arrives, [[spoiler:[[NightmareFuel with the Chryssalids chasing you the whole way.]]]]
* SecretWar: ZigZagged.
** There is zero doubt among humanity that aliens are invading, given that their actions are public and tend to result in quite a few civilian casualties, especially after the first Terror mission. However, XCOM itself is a secret organization which is never publicly acknowledged, referred or alluded to by any public figure. The reason for this is never specifically stated, but is likely a result of the {{Sadistic Choice}}s that XCOM is forced to make: they cannot protect the entire world all at once, and therefore have to choose who to protect. A policy of "protecting who we can by decisions you're not privy to" does not engender public trust.
*** This could also be an attempt to protect their HQ's location, resources, and strategic/tactical movements from overt discovery by the aliens (or any quislings hiding among the populace). This would be an especially prescient precaution given the psionic capabilities of the aliens.
** Played Straight in the conflict between XCOM and EXALT. Both are secret organizations working covertly to undermine each other, XCOM exposing and eliminating their opponents' cells and EXALT working to sabotage XCOM's efforts. As EXALT members are never taken alive and XCOM retains plausible deniability, their shadow war is never known to the world. [[spoiler:When you successfully storm their headquarters and put them out of business, you are shown a news broadcast where the attack is covered up and framed as a minor fire in a building that was successfully put out by the firefighters, with an ironic comment about how reassuring it is that the emergency services still work well despite the alien invasion.]]
* SendInTheSearchTeam:
** The tutorial mission, "Operation Devil's Moon", has Delta Squad sent in to assist a German recon team that sent out a DistressCall. It ends with only one XCOM survivor.
** "Site Recon" in ''Enemy Within'' has XCOM sent in to find out what happened to a Canadian fishing village that has gone dark, possibly due to alien activity, as well as the government response team sent to investigate. [[spoiler: They're [[ZombieApocalypse all zombies]] or Chryssalids now.]]
* SergeantRock: As with ColonelBadass, some of your troops will probably end up like this. Can lean into DrillSergeantNasty with the right voice option;
-->'''Support:''' [healing ally] ''"Rub some dirt on it you wimp!"''
* SeriousBusiness: A news blurb from a low-panic Argentina reports how dedicated football fans refused to leave their stadium despite reports of alien activity nearby during a particular grudge match.
* SelfInsert: The {{Hero Unit}}s include Firaxis staff and Ken Levine from 2K Games.
* SequelHook: The fact that [[spoiler: the Uber-Ethereal mentions needing humanity uplifted for ''something'']] did not go unnoticed by players.
* ShockAndAwe: The vanilla game [[{{Downplayed}} downplayed]] this trope with the Arc Thrower, which was only useful at stunning weakened enemies, repairing your drones or hacking enemy ones. ''Enemy Within'' turns that around with the MEC Trooper's "Electropulse" Tactical Subsystem, a close-range electric attack that fries any unit unlucky enough to be within a few tiles of the MEC, in addition to shutting down robotic units.
* ShoutOut:
** To [=GuavaMoment=]'s LetsPlay of the X-COM series. One of the hero units is Otto Zander, the hero of the series. This can also carry certain unfortunate, unintended implications for people unfamiliar with the Let's Play, as Otto Zander was also the name of a prominent Nazi. (It should be noted that the name choice was intentional in said LP, considering the character development Otto underwent...)
** Also several Achievements:
*** The achievement for building the base all the way to the deepest level available is called "[[Literature/TheLordOfTheRings Drums in the Deep]]".
*** Successfully [[HoistByTheirOwnPetard mind-controlling an Ethereal]] unlocks "[[ComicBook/{{X-Men}} Xavier]]".
*** Winning a mission with an [[AmazonBrigade all female squad]] unlocks "[[Music/RideOfTheValkyries Flight Of The Valkyries]]".
*** Staffing the research department with 80 scientists nets you "Oppenheimer".
*** Researching every possible research project gets you "Edison".
*** Building your first SHIV gets "[[Film/RoboCop1987 You Have 5 Seconds to Comply]]."
*** Capturing an Outsider gets you "[[Literature/TheDresdenFiles The Gatekeeper]]".
*** Winning your first multiplayer match earns "Meet New People. Then Kill Them." This is a reference to an unofficial US Special Forces motto.
*** "Skunkworks", for completing every Foundry Project, refers to Lockheed Martin's aircraft R&D department (officially the Advanced Development Programs), which produced such warplanes as the SR-71, F-22 and F-35.
*** "[[WesternAnimation/CaptainPlanetAndThePlaneteers By Our Powers Combined!]]" in ''Enemy Within'' is earned by fielding a squad of MEC Troopers from all 4 different base classes.
*** Also from ''Enemy Within'', you earn "[[Franchise/{{Terminator}} Rise of the Machines]]" for fielding a squad of at least 4 made up entirely of [[AttackDrone S.H.I.V.s]] and [[MiniMecha MEC Troopers]].
*** "Ours are the Furies", the achievement for completing the final mission of ''Operation Progeny'', is a reference to Literature/ASongOfIceAndFire, where House Baratheon has the motto "Ours is the fury".
*** Yet another from ''Enemy Within'', which is tied to a new mission type (Covert Operations, which are intended to disrupt EXALT cells and gather clues as to where EXALT's main base is): killing three EXALT troopers with the covert operative assigned to the mission gets you [[{{Videogame/CovertAction}} "Remington...]] [[{{Film/JamesBond}} Max Remington".]]
** A soldier mind-controlling an enemy might say:
-->''"[[Series/StarTrekTheOriginalSeries My thoughts to your thoughts.]]"''
** Bradford occasionally delivers several lines when you're in the Situation Room. Some of them are:
-->''"Are you really using our tracking terminal to play ''VideoGame/{{Civilization}}''?! I at least hope you're going for a Military victory."''
-->''"Some nut calling himself [[Series/{{UFO}} Commander Straker]] has been all over the news talking about 'SHADO agents'."''
-->''"...and you're positive the report states that the alien craft crash landed in [[Series/{{Alf}} the garage of a suburban middle-class family... Tanner residence.]] Roger, we'll look into it."''
** Using the Arc Thrower to stun an alien results in soldier dialog. Some of the random bits that play are:
-->''"[[Film/BackToTheFuture 1.21 Gigawatts]], baby!"''
-->''"[[{{Music/Metallica}} Ride the lightning]]!"''
** The Chryssalid autopsy research project is codenamed [[Creator/RidleyScott Ridley]]. [[ChestBurster Very]] [[Franchise/{{Alien}} appropriate]].
** One of the Cyberdisc's abilities is the [[Film/TheLastStarfighter Death Blossom]].
** The EMP Cannon research project's codename is "Ion". Ion cannons in the ''Franchise/StarWars'' universe function similarly to real-world EMP devices.
** [[http://cdn3.sbnation.com/entry_photo_images/7286641/2KGMKT_XCOMEU_Screenshot_DLC_Slingshot_09.jpg One helmet]] in the ''Slingshot'' DLC is obviously inspired by [[VideoGame/HaloReach Emile's]] [[http://farm5.staticflickr.com/4144/4969654691_e4660762d3_z.jpg skull-patterned visor]].
** When one of your soldiers spots an alien squad, they might announce it by saying, "It looks like [[Film/ETTheExtraTerrestrial E.T. phoned home for backup."]]
** Another achievement called [[Videogame/TeamFortress2 G'day]] when you [[SniperDuel kill an EXALT Elite Sniper with one of your own]].
** One of the options you can select in ''Second Wave'' mode is the requisite that psionics can only be learned by interrogating psionic aliens. This option is called [[TabletopGame/{{Warhammer40000}} The Greater Good]].
** One of the possible clues to the EXALT headquarters' location is that it's "Not in a country you can play in [[VideoGame/{{Civilization}} Civilization V]]", another Firaxis game.
** The Seeker autopsy research project is codenamed [[Creator/HPLovecraft Lovecraft]].
*** There's also a Council mission with a highly Lovecraftian feel: All contact with a fishing village in Newfoundland is lost after a strange ship arrives, and your team is sent to investigate. [[ScrewTheRulesIHavePlot They even bend the rules a little to make the comparison better]] [[spoiler: as the mission features zombified townfolk, even though they should've turned into Chryssalids by the time you get there.]]
** ''Enemy Within'' introduces medals that you can award to your soldiers for buffs. One of them is named the [[Franchise/MassEffect Star of Terra]] by default.
** The trope FastballSpecial isn't actually used, but soldiers occasionally say this word-for-word when throwing a grenade.
** The [[spoiler:base defense mission]] in ''Enemy Within'' is code-named "Ashes and Temples", a reference to Thomas Macaulay's classic poem [[http://www.bartleby.com/360/7/158.html Horatius at the Bridge]], an epic about Horatius Publius and his companions as they HoldTheLine against assaulting enemies.
--> ''Then out spake brave Horatius,''
--> ''The Captain of the Gate,''
--> ''"To every man upon this earth,''
--> ''Death comes soon or late.''
--> ''And how can a man die better,''
--> ''Than facing fearful odds,''
--> ''For the ashes of his fathers,''
--> ''And the temples of his gods?"''
* ShutUpHannibal: A Sniper may do this to the [[spoiler: Uber-Ethereal]] mid-speech.
* ShootTheMedicFirst:
** {{Averted}} against aliens, as they don't focus on medics any more than other soldiers.
** Advised when you're facing EXALT, because their Medics can heal other EXALT units with their version of the Medikit, and the Elite version's HealingFactor also heals fellow soldiers within close proximity.
* ShortRangeShotgun: For emphasis, ''pistols'' will be more accurate than them at greater ranges for the base weapons. Later shotgun variants have better range to close the gap a bit, but the "Improved Pistol II" Foundry Project increases pistol accuracy to widen it again. A tip will even mention using the pistol to make shots against far away enemies if equipped with a shotgun.
* SinisterShades: Thin Men wear these in order to hide their HellishPupils.
* SkewedPriorities: Aliens in Terror! missions will often target civilians even when there are soldiers about to shoot them.
* SleevesAreForWimps:
** The gene-modded troopers in ''Enemy Within'' wear lighter suits with no armor or clothing over their arms. No matter what armor or customizations, their arms will still be exposed.
** Elite EXALT operatives can be identified by their rolled-up sleeves, which also exposes their [[TattooedCrook tattoos]].
* SpyCatsuit: The Psi Armor is very form-fitting, even if it's more armored than most examples. Tone it in black to complete the effect.
* SoleSurvivor: The tutorial mission ends with only Delta 2 from Argentina surviving. Losing three-quarters of your initial squad ''in the tutorial'' sets the tone for the rest of the game: it will not be easy. People ''will'' die.
** You can avoid that if you skip the tutorial, although you'll miss the chance at some early loot and a starting Heavy. [[EarnYourHappyEnding Unless of course you use that first tactical mission to utterly annihilate every X-Ray you see and come out with zero casualties.]]
* SpareBodyParts: In ''Enemy Within'', you can give your soldiers a second heart. This ensures that, [[CriticalExistenceFailure rather simply dying]], they are always Critically Wounded the first time per mission their health drops to zero and extends their bleed out time, giving you a better chance to resuscitate them. As a bonus, they also don't gain the permanent Will penalty for having been Critically Wounded.
* SuddenlyVoiced: EXALT operatives normally have their radio chatter shielded by massive static, but if you hit them with a flamethrower, you can hear them clearly say things like "I'M LOSING CONTROL OF THE SITUATION!". Interestingly enough, some of them seem to have a slight Asian accent no matter what country EXALT is in.
* TheSpartanWay: As you lose your veteran soldiers, you'll need to bring in rookies to replace them. The problem is that rookies are much less capable, so there's a vital need to train them up - and the only way to do that is to send them on missions. The lucky ones get to tag along with the vets on a mission, which means that it's entirely likely that the first alien they'll see will be a Muton or Chryssalid. But if you have a [[TotalPartyKill Code Black]] with your vets, you may end up sending an entire squad of rookies on a mission that will definitely get some of them killed. But at least the survivors will be tougher for the experience.
* SpitefulAI: During Terror missions, enemies will often attack civilians instead of your soldiers if they're in a situation where they only have one move before your squad ventilates them. Sometimes, they'll do it even when they're in a secure position and your soldiers make easier targets.
* SpySatellites: Used to search for [=UFOs=] outside of your main base's radar coverage. Keeping satellite coverage heavy is important to keep the various nations from withdrawing from the Council (and more importantly, funding ''you'', as only countries with satellite coverage will give you monthly donations) and the aliens visible and chaseable. If you don't diligently shoot down [=UFOs=] with your interceptors, your satellites can be shot down, necessitating an expensive and time-consuming replacement. Fortunately, you can also research stealth enhancements for your satellites at the Foundry, making them harder for the aliens to find.
** Satellite coverage has another, less-advertised result: if a country has coverage at the start of a month, it will no longer be possible for the aliens to start abductions in that country. Thus, in addition to giving you the continent-specific bonus, locking down a continent with complete coverage will stop its panic level from rising (assuming you don't fail any Interceptions, Raids or Terror Missions).
* StormingTheCastle: Two story missions and one optional mission.
** The assault on the [[spoiler: alien base, which will be XCOM's first encounter with advanced psionic abilities. [[DiscOneFinalDungeon Not that it slows the alien invasion much]].]]
** The final mission is an assault on [[spoiler:the [[FinalDungeon Temple Ship]], pitting XCOM against the masterminds in charge of the alien invasion. Succeeding here stops the invasion in its tracks.]]
** Once you finally narrow down the location of EXALT's HQ, you can choose to storm it to eliminate them as a threat.
* StrongFleshWeakSteel: It is possible, with Titan Armor and Chitin Plating, to make a Major-ranked Assault ''tougher'' than an armored SHIV. Assaults gain an ability that gives them bonus health based on the armor they wear. With both the armor and plating equipped, an Assault can have up to 29 hitpoints, making them far more durable than even an Alloy SHIV, which can only have up to 18 hitpoints.
** Subverted with the inclusion of the MEC Trooper, which can have the same amount of hitpoints by using a Tier III "Paladin" MEC Suit with the "Shaped Armor" Foundry Project. Coupled with abilities that allows a MEC to reduce incoming damage and even repair damage taken, [=MECs=] can often soak up more damage than an Assault can.
* StuffBlowingUp: Grenades and rocket launchers are extremely effective at completely blowing the stuffing out of the aliens. The downside is that they blow up any salvageable material (including Weapon Fragments, if you kill an alien with them) in their blast radius, but hey, if you get the opportunity to completely waste a group of weak enemies, then by all means, annihilate them! Better than losing your squad. Also, melee-only aliens like the Chryssalids don't provide Weapon Fragments in the first place, so feel free to blow them to pieces. They also tend to be bunched up when initially encountered.
** You can also use them to just blow up the aliens' cover, allowing your other troopers to shoot them without an accuracy penalty. Using them to soften up a group of very tough enemies is also viable, as Weapon Fragments are only lost if they're ''killed'' with explosives.
* StupidityIsTheOnlyOption:
** The tutorial involves the initial squad charging into unknown territory and subsequently getting ambushed while investigating a German soldier acting oddly. Because of the structure of the tutorial, it happens while trying to disarm the (armed, unresponsive) German soldier by sending one man to him in plain view before the team establishes Overwatch.
** Even if you know your mind control ability is only temporary, you can't have your squad shoot or stun your mind controlled subject until he breaks free, unless you use up your limited amount of explosives. Having the aliens kill it for you gives your squad a Will penalty for the rest of the mission, since it's marked as a teammate while mind controlled, so that's out too. It gets ridiculous when one of your squad ''panics'' because a mind-controlled Sectoid gets blown up.
*** The Will penalty was removed in a patch, but you still can't preemptively apply a shotgun slug or Arc Thrower to their head. Of course, this also means that the aliens can't do so when they have ''your'' forces mind controlled.
* SuicidalOverconfidence: {{Zig Zagged|Trope}}. Most aliens avert this; they'll sound the retreat, fall back to better cover and call for help if they feel they're outnumbered and/or outgunned. Chryssalids and Muton Berserkers play this straight; these two will (usually) charge ahead instead (note that they can move, but not attack in your turn), allowing you to shoot them point blank in the face. In the case of the Berserkers, there's a good chance an Assault can shoot one 3 times in one turn with the right abilities and when in the right position.
* SuperpowerLottery:
** How receiving the [[PsychicPowers the Gift]] works. The game uses [[http://forums.nexusmods.com/index.php?/topic/888002-psi-soldier-chance/ a complicated formula]] to determine if the soldier you enter for testing will emerge as Psionic, and can even be [[SaveScumming Save Scummed]] to get good results.
** When the "Training Roulette" modifier is on. For every [[DiscOneNuke Bullet Swarm Sniper]] or [[BulletTime In-The-Zone Assault]] you find yourself blessed with, you'll get a Squadsight Sniper [[UselessUsefulSpell with Grenadier and Revive]].
* SurpassedTheTeacher: [[spoiler: The entire invasion was really a training program intended to uplift humanity to the point where we could serve as part of the Ethereals' army. Unfortunately, like most other alien invaders, they underestimated just how [[HumansAreWarriors tough]] humans are. [[NintendoHard Assuming you win.]]]]
* SurprisinglySuddenDeath: Always a possibility, depending on your soldiers' health. Aliens can pop out from rooftops and kill soldiers in one shot, Berserkers can [[BarrierBustingBlow smash through walls]] to kill someone, even if you can't see them, and Sectopods can launch rocket barrages that can annihilate your squad from well beyond visual range.
* SuspiciouslySmallArmy: XCOM can only field 99 soldiers in total, which is barely more than two platoons at best, and then send a maximum of 6 soldiers to clear a city of aliens. Yet they're tasked with stopping an entire global invasion. Somewhat justified, as XCOM is more of a black-ops unit tasked with assaulting key objectives, while leaving the heavy fighting to the rest of the Earth's militaries.
** Additionally, XCOM's mandate isn't to fight the war directly, but rather to ''win'' it, by identifying the aliens' weaknesses and exploiting them to stop the invasion. XCOM isn't a conventional military organization, but rather a very narrowly-focused, specialized unit, like a self-contained Delta Force.
* TakeCover: The biggest gameplay change over the original (aside from the removal of Time Units) is this. Your troops will hunker down next to various objects when possible and this is absolutely vital to not getting your soldiers' heads blown off. Technically, you could take cover in the original X-COM too, but only through micro-managing your troops' time units to duck out from behind walls before ducking back in; here, it's all automatic.
* TakeThat: A subtle one to ''VideoGame/TheBureauXCOMDeclassified''. William Carter, the protagonist of the game, is available here as a Hero unit, but he's inferior compared to the other XCOM Heroes, and even your regular soldiers can eventually surpass him in everything but health. [[SoOkayItsAverage Pretty much mirrors the fans' reaction]].
** Carter is also the only fictional Hero unit obtainable, so what if [[FridgeLogic it's meant to be a representation of Carter as an X-COM unit?]]
** EXALT troopers closely resemble Bureau operatives and have [[ArtificialStupidity questionable]] AI.
* TakeYourTime: What's that? A gigantic ship huge enough to cause earthquakes where it pleases just appeared out of nowhere? It'll wait as long as you want for you to attack it. [[spoiler: Which is exactly what it wants you to do since you'll be bringing your best Psionic Soldier on that attack.]]
* TechnologyPorn: Once you complete certain research projects, construct a building for the first time or manufacture certain weapons or vehicles for the first time.
* TechLevels: Ballistic Weapons < Laser Weapons < Plasma Weapons. Several class abilities refer to the weapon's tech level.
* TeleportingKeycardSquad: Thin Men sometimes drop out of the sky after you complete some objectives in Council missions. The ''Slingshot'' Council missions have a Chyrssalid and several Mutons do the same. In ''Enemy Within'', EXALT sometimes does the same in both kinds of Covert Ops.
* ThemeNaming:
** All the research project [[OperationBlank codenames]] for the various plasma weapons and the Alloy Cannon are various types of [[AnimalThemeNaming birds]].
** In ''Enemy Within'', the three survivors rescued in "Furies", the final mission of ''Operation Progeny'', are nicknamed [[ReligiousAndMythologicalThemeNaming "Alecto", "Megaera" and "Tisiphone"]], three of the Greek Erinyes, also known as the Furies.
* ThereWasADoor: Your squad's A.I. will always use the straightest possible path to get to a given location, often causing them to smash windows en route unnecessarily. And of course, you can use rockets and grenades to create convenient 'shortcuts'...
* ThisCannotBe: [[spoiler: The Uber-Ethereal when you kill him. Shades of WhatTheHellHero as well. He genuinely believed that humans would willingly join the Ethereals to fight whatever bigger threat they were preparing for, and killing him destroyed their only source of information.]]
* TitleDrop: The tooltip for "Autopsy Required"[[note]]Only shows up when looking at the Target Info of an alien that hasn't been autopsied yet[[/note]] starts off with "Enemy unknown".
* TortureTechnician:
** Not a character, but a continent: South America's continent bonus is called "[[WeHaveWaysOfMakingYouTalk We Have Ways]]", allowing XCOM to perform Autopsies or Interrogations instantly. Pain is the universal language!
** Dr. Vahlen, who designed the interrogation system, an off-screen process which avoids the translation barrier by almost literally ''ripping the information out of their brains and/or implants''. Officer Bradford admits that he is a bit creeped out by her methods.
*** The end of the first mission in the ''Operation Progeny'' mini-campaign in ''Enemy Within'' has Bradford explicitly mention how Dr. Vahlen is also good at interrogating '''humans'''!
* TotallyRadical: Some of your soldiers' order confirmations veer into pretty silly territory.
--> (When moving): ''"Starting to motor!"''
--> (When moving): ''"Rodger dodger!"''
* TragicMonster: In a way, [[spoiler:''all'' the aliens qualify. Each was its own separate race until the Ethereals had them twisted and changed for their own purposes. When they were finally deemed as "failures," they were then simply converted into proxy soldiers for the Ethereals' next invasion.]]
* TrailersAlwaysSpoil: Some of the trailers for ''Enemy Within'' spoil the [[spoiler: attack on XCOM HQ]].
* TransformingMecha: The Cyberdiscs can transform between a nigh-invulnerable but unarmed disc form and a vulnerable but heavily-armed floating insect-bot form.
* TrickBomb:
** The Support's [[SmokeOut Smoke Grenades]], which can also be enhanced to double as a combat stim that buffs your troops, or just provide extra-thick concealment fog.
** The Sniper's [[EnemyDetectingRadar Battle Scanners]], which are good for revealing distant enemies or invisible foes.
** ''Enemy Within'' introduces several new grenade types.
*** [[FlechetteStorm Needle Grenades]] cover a wide radius but don't go through cover (useful if you don't want to shred cover you intend to take, or have a guy hiding right behind a chest-high wall next to a bunch of Thin Men).
*** [[InvisibilityCloak Ghost Grenades]] turn everyone in the area invisible for a turn, perfect for sneaking around enemy interception shots or patrols.
*** [[ThrowingTheDistraction Mimic Beacons]] send out decoy noises to draw enemies into your kill zone.
*** [[BlindedByTheLight Flashbangs]] greatly reduce enemy's movement and aim, as they stumble around blindly.
*** [[DeadlyGas Gas Grenades]] poison enemies and force them to avoid the poison clouds (and their aim is terrible when they're poisoned).
* TwentyFourHourArmor: Equip your soldiers with Titan Armor and its variants, and you can see them relaxing and exercising in the Barracks with it still on. Apparently, the armor is environmentally regulating and very agile, plus probably being a real pain to take off and soldiers potentially needing to scramble at any minute. Still, one must wonder where that "evacuation" port is.
* TwentyMinutesIntoTheFuture: The game is set in 2015, but the world is almost exactly the same as it was on the game's release date in terms of technology and geopolitics, with a few exceptions. For example, military technology is slightly more advanced, Scotland seems to be an independent country, and gas costs around nine or ten dollars a gallon (though the last may be due to the alien invasion rather than an ongoing energy crisis).
* {{Unobtainium}}: Elerium and the alien alloy. Neither of them can be found on Earth or artificially created, meaning your only source is from the cold dead hands of the aliens.
** So far. Both Dr. Shen and Dr. Vahlen muses that, with a few years of concentrated research, they could make the stuff become widely available. Problem is, you don't have months available, let alone years.
* UnusableEnemyEquipment:
** Played Straight at first, but {{Justified}}; alien weapons self-destruct when they're killed (without using explosives). Subverted later on, as you can capture intact alien weapons if you use an Arc Thrower on the enemy (but still can't swap it in-mission, {{Justified}} as they're not built to human ergonomic standards and would be awkward to use at best). Additionally, you'll soon be building your own, human-adapted weapons and modify the ones you capture in the same fashion.
** ZigZagged in ''Enemy Within''. EXALT weapons are recovered after missions and can be used by your own soldiers. However, they're [[PaletteSwap mechanically identical]] to your own weapon counterparts and [[VendorTrash are meant to be sold once you decide you have enough]]. Played straight with the unique gene mods on most of their Elite units, which are "Iron Skin" (Elite Heavies)[[note]]reduces damage by 25%[[/note]], "Regen Pheromones" (Elite Medics)[[note]][[HealingFactor regenerates the health of the Medic and nearby friendlies by 1 every turn]][[/note]] and "Adrenaline Rush" (Elite Operatives)[[note]][[TurnsRed increases Aim and Critical Chance by 10% when injured]][[/note]]. {{Justified}} due to [[EveryoneHasStandards surpassing Dr. Vahlen's ethical limits]].
** Completely intact [=UFOs=] can't be commandeered after being secured, even if you've reverse-engineered their navigation, power and propulsion systems. They can only be dismantled for their components and raw materials. [[spoiler:Then again, once you reach the late-game, you don't ''need'' a commandeered alien ship, as XCOM Firestorms with fusion lances can handily win dogfights with anything the aliens send at you.]]
* UnstableEquilibrium: Early-game is typically the hardest part of the game. You've got no territory, little income, inexperienced soldiers, no technology and the aliens outnumber you. Later on, you have the option of getting goodies that even the aliens wish they had and soldiers with ImprobableAimingSkills who can mow down aliens like Rambo even with [[RockBeatsLaser basic ballistic weapons]] and snipers who can pop the aliens' heads from across the map. Then psi powers enter the game, and the rules change... and again, once you have one or more psi troopers of your own.
** Some veteran XCOM players call this the "Snowball" effect: at first, your chances of victory seem very low, but as you gain momentum and more advantages, you quickly start to overpower your previously unstoppable enemies.
* UrbanWarfare: All alien abductions and Terror missions take place inside major population centers. ''Enemy Within'' adds Covert Operations against EXALT and even a few urban UFO crashes to the list.
* UpdatedRerelease: Unlike the PC version, ''Enemy Within'' was released as the ''Commander Edition'' for the PS3 and {{Xbox 360}}, which includes the base game and all {{DLC}}.
** The PC version plays with it. While the game is still called ''Enemy Unknown'' in the Steam game library, ''Enemy Within'' adds a game launcher that lets the player choose between playing the original ''Enemy Unknown'' and the expansion.
* UpliftedAnimal: [[spoiler: Most of the aliens that serve the Ethereals have been conquered and uplifted or altered to some degree in their search for "gifted" species. The Chryssalids are the most striking example, since they began as feral animals... and didn't really evolve from that state.]]
* VendorTrash:
** Some items, usually damaged ship components, alien surgery equipment and the like. Vendor Trash items are clearly labelled in your inventory as "having no use for research projects".
** In ''Enemy Within'', EXALT weapons are only cosmetically different from your own, including the basic ballistic weapons. Since you already have an infinite supply of statistically identical weapons, you might as well make some money. Don't get too excited, though: they're only worth 1 or 2 credits.
* TheVeryDefinitelyFinalDungeon: [[spoiler:The Temple Ship, which floats ominously over the Atlantic Ocean after you recover the Ethereal Device.]]
* VFormationTeamShot: On the box art. Also, your team prior to deployment will stand like this, allowing you to review them and their gear, standing around, looking awesome, [[http://www.youtube.com/watch?v=PJ1rL8Ts7Ro with appropriate rockin' music playing in the background]]. Contrast this with the ''after mission summary'', especially when things go south.
* VideoGameCaringPotential:
** Unlike the original game, you'll (probably) get attached to your soldiers this time, and not just treat them as {{Red Shirt}}s. Especially the [[SoleSurvivor Argentinian Heavy]] from the tutorial.
** There's even an achievement, called "Ain't No Cavalry Comin'", which you earn if you take a soldier through every single mission. It's not enough to merely have him/her survive from the very start until the end of the game, but he/she must take part in each and every mission you take on. If you play with the tutorial enabled, this soldier will inevitably be the aforementioned Argentinian Heavy because he's the only one to survive the tutorial mission, which does count towards the achievement.
** Name your soldiers personally if you really want to get attached. Go ahead, name one of the soldiers after someone you know and care about deeply and see how much care you take in not getting them blasted by an alien. This does lead to awkward explanations to your loved ones of how their name ended up on the memorial wall, though.
* VideoGameCrueltyPotential:
** Have four Heavies? Check. Four civilians next to a truck you wanna use for cover? Check. Sending in anyone to rescue them? Nah. Sending a rocket to blow it to hell along with the four civilians? Check. [[KarmaHoudini Earning an Excellent rating? Check]].
** Rookies cost $10-$15 each, which is pretty cheap (except very early on in the game). If one pisses you off by [[ATeamFiring repeatedly missing the alien they're standing next to]], the options of making them go check out the scary noise in the building on their own, or drawing fire, or just plain being used as bait always exists.
** Is there one little Sectoid left on the map? Check. Have a Shotgun Wielding Assault with Ghost Armor and an Alloy Cannon? Check. [[TheresNoKillLikeOverkill It WILL bring a smile to your face when you decorate the wall/tree/car/bulkhead that Sectoid is hiding behind with its innards.]]
** Is there a single Muton Berserker left on the map? Check. Can one of your soldiers use Mind Control? Check. Now take the Berserker, move it to an open area with no cover, then have your squad line up in firing range, turn on Overwatch, and wait for the Mind Control to wear off. Cue MoreDakka.
*** Better yet, in ''Enemy Within''. Is that Berserker close to one of your MEC units? Does it have the "[[PowerFist Kinetic Strike Module]]"? ''Punch it clear across the map.'' It gets even better if it's an EXALT agent. You can punch them into cars so hard the cars ''explode''.
** Mind Controlled a Muton or Elite Muton? Does he have buddies around? Why not have him stroll over to his friends and then casually drop his own grenade at his feet?
* ViolationOfCommonSense: One wrong click, and you sent a soldier out of cover with [[ThisIsGonnaSuck a Sectopod warming its laser cannon in anticipation]], and your remaining two soldiers have no moves that can affect the enemy's hit chance? If the Sectopod is the only enemy, just have them run out of cover as well, standing two tiles apart from each other. [[SchmuckBait When presented with a delicious cluster of enemies stacked too far away to hit with one laser blast]], [[ArtificialStupidity the Sectopod will use its first turn to charge a rocket barrage]], ending its turn and giving you a free move to escape.
* VirtualPaperDoll: You can customize your soldiers to a great degree, particularly in ''Enemy Within''. Names, nicknames, physical appearance, armor color, voice, language, and hats are just some of the things that can be modified, [[AnyoneCanDie which makes it all the more painful if they get killed]].
* VomitIndiscretionShot: Zombies will violently heave on their third turn. It's a helpful visual reminder to deal with it before you have to stop worrying about the zombie and more about [[ChestBurster that new Chryssalid]].
* WalkieTalkieStatic: "EXALT Activity!" plays this sound when it's EXALT's turn during a covert op, and they also seem to make this noise to each other when communicating.
* WakeUpCallBoss:
** The Chryssalids.
** Regular Mutons and Heavy Floaters are not-so-subtle nudges that it's time to upgrade to Laser and Plasma weaponry respectively if you haven't already.
** On Impossible difficulty, Thin Men. They appear before the first month is over, have 6 HP each (double what they have on Easy/Normal) and can do up to 6 damage on a non-critical hit. Given that most of your soldiers won't even ''have'' 6 HP at this point, nearly any successful shot from a Thin Man will result in a OneHitKill. They also often attack in groups and have very high aim, not to mention also being able to poison you. They are still threats on lower difficulties, but not to the same extent.
* WallOfWeapons: Between the Barracks and the Control Room is the Armory, which naturally sports one of these. It only has ballistic weaponry, however.
* WarMemorial: In the Barracks you can go to a memorial to fallen soldiers, which will list all of the units that have [[FinalDeath fallen in gameplay]] (including the three [[ButThouMust killed off in the tutorial mission]]).
* WaveMotionGun:
** The Sectopod has ''two'': a fusion lance for burning your dudes to a fine, ''fine'' ash, and a plasma beam for the reaction shots.
** The Battleship UFO has one, which can be adapted for your Firestorms if you salvage an intact Fusion Core from one.
* WeAllLiveInAmerica: No matter which country you deploy in, the buildings and cars (especially the yellow cabs) will often look like American cities or towns, not to mention the complete lack of accents for your soldiers prior to ''Enemy Within''. Occasionally, you'll also find maps which are inexplicably European or Chinese urban areas. Since each map is hand-crafted, however, this is understandable.
* WeAREStrugglingTogether:
** Averted for the most part. The Council is made up of most of the G20 countries and a few others that give you money and support to keep everyone alive. That said, countries will bail if they feel they would be better off on their own.
** Several news blurbs mention how many rival political and intellectual groups are blaming the alien attacks on each other.
** This is why Zhang defects to XCOM during the special Council missions included in ''Slingshot''. He realized that the Triads squabbling for money and power is kinda pointless when the Aliens are attacking everyone.
** Finally played straight with ''Enemy Within''. EXALT is another human faction that seeks to use the alien's "gifts" to empower themselves and directly opposes XCOM.
* WeBuyAnything: The good ol' Gray Market is the secret auction house for XCOM's funding nations and if you don't think you're going to be using that pile of Sectoid corpses (though you can craft stuff with them, so don't sell too many) you may as well sell them for money. Early-game, this will probably be your primary means of income.
* WeHaveReserves: The aliens certainly seem to work off this mentality, as does EXALT in ''Enemy Within''. Losing several high-ranking troopers midway through the game can make you do it as well. Throwing dozens of rookies into the meat-grinder can yield a handful of solid squadmembers via Darwin.
* WeirdMoon: Each return trip from a mission shows your Skyranger flying toward a full moon on a clear night, no matter what the date or Mission Control time actually is. To top it off, it's an unskippable in-engine animation so you ''will'' be seeing it quite often.
** Additionaly, most maps take place either at night or at day. Most maps don't switch between the two time periods, so it is very likely that your soldiers will arrive to the mission at noon only for it to be as dark as midnight. Also inverted by the times you deploy on a map where the sun shines bright even if it's 3 AM.
* WelcomeToCorneria: The original game had this problem with Bradford's limited, often-repeating mission briefings, but ''Enemy Within'' rectified it somewhat by adding more descriptions.
* WhatHappenedToTheMouse:
** One of the Large Scout ship maps has an empty, still-running truck of a civilian who came to investigate and left a trail of flares leading to the ship. This isn't commented on, and nowhere in the map is this person's body, living or otherwise.
** Most of the Escort mission [=VIPs=] as well. Anna Sing, in particular, should be able to provide information on the Alien's abduction methodology, but nothing further is heard from her.
** You never find out what happens to the gassed people that you saved by completing an abduction mission. Same for the people trapped in the alien stasis pods and surgery tables.
** As UFO crashes can occur in urban areas in ''Enemy Within'', you'd think there'd be a few civilians sticking around, or at least their corpses on some of the more brutal crashes. Still, absolutely nobody there, apart from you and the aliens of course.
* WhatTheHellPlayer Dr. Vahlen gets pretty pissed off if you repeatedly capture aliens without an Alien Containment Facility to house them in.
* YouLoseAtZeroTrust: Nations have a Panic Meter that goes from 1 to 5. When it hits 5, they are in grave danger of pulling their funding from the XCOM project by the end of the month (if you fail a Terror mission in their country or incorrectly accuse them of harboring EXALT HQ in ''Enemy Within'', they pull funding immediately, even if they have less than 5 panic), as they decide to redirect their funding to keep their own people under control. You lose the game when you lose eight nations total (half of the founding nations, in other words), regardless of the panic levels in the other nations, as the Council of Nations decides that the project is a failure. This will happen a whole lot more often on harder difficulties. {{Justified}}: [[spoiler: If you lose eight nations, then the aliens successfully mind control the Council.]]
* YouRequireMoreVespeneGas: You've got four basic resource types in this game:
** Money, the Gold equivalent. It's used for pretty much everything. You get awarded by the Council on a monthly basis based on which nations have satellite coverage, as well as for some Abduction missions, Council missions and requests. You can also sell scavenged alien materials on the Grey Market if you're strapped for cash.
** Alien Alloys, Weapon Fragments, Elerium and various specialty items like UFO computers, power sources, and occasionally dead bodies, the Lumber equivalents. These are all used for the research and manufacture of advanced tech, but you can only get them by scavenging after missions. ''Enemy Within'' adds "Meld", which can be collected during missions and is used for Genetic Mods and MEC Troopers. Meld is collected from canisters that degrade over time, so they need to be collected quickly lest they expire. Killing Mechtoids and Heavy Floaters also provides a small amount of Meld.
** Power is actually the Population equivalent, despite its name. All the facilities in your base need power to run, which is provided by constructable Generators. You can't build a facility if it requires more power than is available, but there is no other penalty to having insufficient Power, making it more of a cap on how many facilities you can have at the same time. Power demand also cannot exceed its supply under normal circumstances[[note]]The only way to do so is to play on Easy, which grants bonus Power, then switch to a harder difficulty mid-game[[/note]] and existing facilities continue working at full efficiency even if you manage to do so.
* ZergRush: Surprisingly, not used by the aliens, but by the human EXALT. Their fanaticism and superior numbers means that when they want an objective, many members will dash out into the open to get there faster, knowing that you can't kill them ''all'' before they start flanking your guys.
* ZombieApocalypse:
** Chryssalids can easily cause one if left unchecked during Terror missions, due to those 18 tasty civilians running around.
** "[[spoiler: Site Recon]]" in ''Enemy Within'' takes place in the aftermath of one. [[spoiler: A fishing village has been completely overtaken by zombies (and the Chryssalids that made them). At the end of the mission, [[DeathFromAbove the whole town is flattened by an airstrike]].]]
----

''Good luck, Commander. [[CatchPhrase And remember,]] [[TheOmniscientCouncilOfVagueness we]] [[ParanoiaFuel will be watching.]]''