Video Game / X-COM

aka: X-COM

Vigilo Confido.^note Loosely "I Am Watchful, I Am Necessary"

"You must not fight too often with one enemy, or you will teach him all your art of War."

— Napoleon Bonaparte (attr.)

The brainchild of Julian Gollop and assorted MicroProse personnel, X-COM is a British series of games created in 1993. Players are put in charge of X-COM, a planetary defense agency, and tasked with maintaining X-COM's budget and catching flying saucers (either by storming their landing sites or shooting them down). What follows is a mix of Turn-Based Tactics and resource management. Although the games have a fair amount of randomness, the better player will tend to win.

The first title, UFO: Enemy Unknown (marketed as X-COM: UFO Defense in North America) was a watershed title for the genre. Despite its modest origins, the X-COM legacy was not a solo act: While Gollop's team set to work on a sequel called X-COM: Apocalypse, an in-house crew at MicroProse beat him to the punch in 1995 with a Mission-Pack Sequel: X-COM: Terror from the Deep, set 40 years after the First Alien War. Apocalypse took place another 40 years later in an isolated city, and included the option to play in real-time. The last days of MicroProse (and its acquisition by Hasbro Interactive) saw three Genre Shifted offerings: X-COM: Interceptor (1998), an interquel which kept the base management elements while swapping out the strategy missions for a space-bound flight sim. Next was X-COM: First Alien Invasion, an e-mail game. Then came X-COM: Enforcer (2001), a Gaiden Game which ditched the strategy outright in favor of an FPS. As of March 2016, all three games of the classic series (along with Enforcer and Interceptor) are available at GOG.com^note Link goes to the first game. as well as Steam.

Afterward, the future of X-COM became uncertain due to the rights passing between various companies. In 2010, 2K Marin announced that they were rebooting the storyline: an FPS set exclusively in the USA in The '50s. The fandom's response to the reboot was negative enough that Firaxis Games (a subsidiary of 2K and developers of the Civilization series) were tasked with creating a title closer in-line with the original X-COM. The result was XCOM: Enemy Unknown. The FPS reboot was retooled into a third-person tactical shooter: The Bureau: XCOM Declassified, intended as a prequel to Enemy Unknown. (The game's three separate iterations are documented here.)

In 2016, Firaxis released a sequel to Enemy Unknown which re-imagines X-COM as an underground resistance cell fighting against alien occupiers. The 2020 spin-off XCOM: Chimera Squad is a combination of Apocalypse (on-the-street storyline) and the 3D games (a smaller specialized squad).

Entries in the franchise:

• MicroProse continuity:
  • UFO: Enemy Unknown, released as X-COM: UFO Defense in North America (1994), the game that first began the alien-hunting insanity of the series. In the then-close future of 1999, an Alien Invasion threatens Earth, and X-COM is founded to combat the threat from beyond the stars. The player is thrust into the role of commander, and must manage finances, research, manufacturing, base facilities, government relationships, and of course, sending in ground troops to lay the hurt on the aliens.
  • X-COM: Terror from the Deep (1995), a Mission-Pack Sequel to Enemy Unknown, which meshes the alien invasion themes of the first game with a Ocean Punk Lovecraft Lite game set beneath the seas. Fourty years after the first game, X-COM has disbanded, but the sudden rise of a group of Eldritch Abomination Starfish Aliens from beneath the oceans convinces the fractured governments of the world to start pumping funds back into the project again. It's up to you to fight back the aliens, travelling across the world's seas to combat them.
  • X-COM: Apocalypse (1997), a post-apocalyptic survival-themed game that is quite different to the previous two games. By the late 2080's, the Earth is in ruins and the only hopes for survival lie in Judge Dredd-esque mega-cities, such as Mega-Primus, where the game is set. X-COM is refounded when a race of mysterious horrors from another dimension begin invading, and the player is tasked with both leading the combat group and also managing their political standings, public perception, and reputation with other Mega Corps.
  • X-COM: Interceptor (1998), a spaceship fighter-themed Gaiden Game that is an interquel between Terror from the Deep and Apocalypse. By the year 2066, the Earth's resources are pretty much depleted, and humanity seeks a new home with better resources. With the player as the commander of X-COM's space station, they find that the aliens from the first game aren't quite done with humanity just yet, and it falls to you to keep humanity's fledgling space colonies safe with their star fighters and combat bases.

• Hasbro continuity:
  • X-COM: First Alien Invasion (1999), an e-mail based multiplayer Player Vs Player skirmish.
  • X-COM: Enforcer (2001), a Third-Person Shooter.
• Firaxis continuity:
  • XCOM: Enemy Unknown (2012)
    • XCOM: Enemy Within Expansion Pack (2013)
  • The Bureau: XCOM Declassified, prequel to Enemy Unknown developed by 2K Marin (2013)
  • XCOM 2 (2016)
    • XCOM 2: War of the Chosen Expansion Pack (2017)
  • XCOM: Chimera Squad (2020)
  • XCOM Legends (2021, still in Early Access)

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The X-COM series or multiple entries in it, provide examples of:

Tropes A to C

• A-Team Firing: Grumble... Most recruits will hit everything except the aliens.◊
  • This is less the rookies' fault as it your weapons. This is especially evident when using Auto Fire (which makes soldiers shoot 3 less-accurate shots in rapid succession). Agents can even be firing an accurate weapon like any of the Rifles at point-blank on full auto and have the shots knock down the walls and trees behind an alien without even grazing it. Aimed Shot (a single, more-accurate shot that eats up more of your Time Units for the turn) is practically a necessity for any enemy who isn't in point-blank range. On the other hand, Plasma weapons are vastly more accurate than ballistics or lasers; with those in place, even an auto-shot will prove effective with enough training in Firing Accuracy.
    • An unusual case comes from the starting Rifles in X-COM: the basic rifle is described in the fluff as being a sniper-capable weapon which has burst fire, and it shows - the weapon is more accurate than any plasma or laser weapon if you used Aimed Shot, but its accuracy takes a serious nosedive if you fire it on auto.
  • Auto shot is preferable early on when you know even the soldier's aimed shot will most likely miss. First, it has a chance to hit aliens multiple times, stray bullets will sometimes hit other aliens (even those you didn't notice), and if the alien can see you, a single burst will only trigger reaction fire once as opposed to aimed or snap shot which trigger reaction on every shot. Even if you only have a 20% hit chance, in a burst of three it means 48.8% chance that at least one will hit. Once you have laser weapons, you most likely use auto shot at every opportunity.
  • Snap Shots, on the other hand, are only useful if you're standing nose-to-nose with an unarmored alien; otherwise you hit air. You're better off spending your TUs on 1-2 Auto-Shots than flushing them down the toilet on a Snap Shot. Waving your gun around like a lunatic and blindly spraying bullets into the air is preferable, literally, to carefully kneeling and firing off a Snap Shot.
  • Experimentation has shown a few oddities with accuracy in the first two games. In particular, the quoted % accuracy is actually understated a majority of the time. The reason for this is that a "miss" is not actually a miss, but rather a random deviation applied to the bullet. If you're lucky (or at point blank range), this deviation will be small enough that the bullet hits anyway.
• Adventure-Friendly World: See Crapsack World. This works out fine as the backstory of a hyper-lethal squad combat game: the utter monstrosity of your enemy means that as long as any humans survive, the Non-Entity General can always find vengeance-crazed replacements for troops lost in combat, or at least someone willing to die for a carrot, and there is an unending supply of alien baddies to kill, capture and vivisect. But taken out of context, X-COM is essentially sending unaccountable death squads against an enemy that can never really be beaten without desperate measures.
• Airborne Mook: The Floaters, their equivalents in the sequels, and various terror monsters.
• Alien Autopsy: The player's scientists can perform these to learn more about the enemy.
• Aliens Are Bastards
  • The first two games played straight.
  • Would have been subverted with the canceled Alliance, where the stranded X-COM team form an alliance with the friendly aliens against the hostile ones.
  • Downplayed with in Apocalypse. The new aliens are certainly bastards, but some of the ones we've been previously familiar with now co-exist peacefully with humans.
  • The reboot trilogy (Enemy Unknown/Within, XCOM 2 and Chimera Squad) plays it both ways: the Ethereals are almost universally bastards, but their various Slave Mooks are as much their victims as humanity is. In fact, as EXALT and Shrike can attest, humans can be bastards too.
• Alien Blood:
  • Green and Yellow seems to be most common ones.
  • Ethereals have silver blood (though it's dark red in its Autopsy picture).
  • Aquatoid blood is orange.
  • Lobsterman blood is teal.
• Alien Invasion: Though alien threat comes from a new source—space, underwater, and another dimension respectively.
• All Deserts Have Cacti: Any desert you visit in UFO Defense has Cacti. Even the deep Sahara or the Rub al Khali. Even the desert in Enforcer has cacti.
• All Your Base Are Belong to Us: A major gameplay element; you have to design your hidden underground bases with defense in mind, since aliens will eventually find and attack them. Later in the game, of course, you get to do the same to them. (Or earlier, since unless you're doing a really bad job, you'll find some alien bases before they find yours.) Innovations in technology will eventually provides missile and psychic defenses to fend off UFOs or, in the case of the latter, cloud detection of the base completely. The Skyranger isn't exactly a safe haven either, both on the ground or in the air.
• Alliance Meter: UFO and TFTD has this in form of Funding Nations. Scaled up in Apocalypse with 25 factions waging corporate wars for political and economical power in Mega-Primus during the alien invasion.
• America Saves the Day:
  • Zig-zagged in UFO/TFTD; X-COM is an international organization, but the US is your biggest financial contributor in UFO/TFTD. Geographically, it's one of the most difficult regions to defend (the most difficult being Australasia) while still keeping a radar umbrella over the other donors, separated as they are between two vast oceans. Not a good site for a starter base; keeping a close watch on it with Skyrangers until you can afford a secondary base is the best way to go.
  • The logic behind this trope is eviscerated in the manual for Interceptor, which mentions that one of the first nations to step up and do something about the alien threat was Japan, forming a specialized task force for the purpose - and having to disband it after five months with no successful UFO interceptions, because a single nation simply didn't have the money or equipment to adequately deal with things, leading to the formation of the multinational X-COM.
• And Your Reward Is Clothes: Each difficulty level you beat in Enforcer (in single play) unlocks a few new skins for the title robot.
• Apocalypse How:
  • The result of failing to defeat the aliens (and sometimes even when succeeding). See the more detailed AP examples in each games respective sections.
  • Interceptor: If you fail, the alien superweapon utterly obliterates Earth, leaving a smoldering husk behind. You get to turn the tables on them, though, using the Nova Bomb to cause a supernova in their pocket dimension solar system. Technically, you can do it as much as you want, which is a little frightening.
• Appropriated Title: The series started as UFO: Enemy Unknown. It had to relabel itself X-COM when somebody complained there's already a game called UFO.
• Armchair Military: The "rear commander" tactic. Since high-ranking officers contribute to the Morale level (and significantly hamper morale when they get themselves killed), it will behoove you leave them behind in the Skyranger. The officer will continue to gain EXP and receive promotions, with the rookies and squaddies stuck doing all of the legwork. Once you go into psionics they can still make themselves useful, either mind-raping aliens or (if they're too weak psychically) scanning them with the Mind Probe. They can also use the Blaster Launcher to bombard enemies from long distances (though Save Scumming is advised if firing it from inside the Skyranger, as there's a chance of the Blaster Bomb hitting the inside of the hull).
• Armor Is Useless: Armor won't be much use to somebody who just got shot right in the sphincter, either from behind or one floor below. Fortunately, this holds true for the aliens and mechs, as well.
  • A soldier with maximum health and the best armor can still be killed in one shot if the damage roll is high enough. Even the best armour has at best a 50/50 chance of stopping a Heavy Plasma shot, though it does make troopers immune to many human weapons and it provides much better protection than most alien units have. To clarify, X-COM soldiers take 0 to 200% of the listed damage from firearms; 50 to 150% from explosives. Unarmoured troopers can survive several heavy plasma blasts and take absolutely no damage... only to be offed by a single pistol shot the next turn.
  • The manual does state that the default coveralls do offer excellent protection from modern weapons, although it skimps over the plasma resistance capability...
  • Zig-Zagged in Terror: The front of the Ion Armor can let soldiers take point blank Sonic Cannon blasts or Lobstermen's claws and take no damage as long as it hits the front armor (unless random chance screws you over), but still played straight with Bio Drone explosions and Tentaculats. Also, Ion Armor is much weaker at the sides, meaning the alien waiting around the corner can easily take out your soldier if you're not careful.
  • Averted in Apocalypse. Megapol Armour is fairly competent, particularly against light friendly fire and early disruptor weapons, but is terrible against devastators. Marsec's flying armour is weaker but allows flight. On the other hand, X-COM manufactured "Disruptor Armour" transforms soldiers into nigh-unstoppable death machines who can practically waltz through multiple explosions without even taking a mortal injury. The shields certainly help, though.
• Attack Drone
  • Cyberdiscs and Bio-Drones.
  • Enforcer's protagonist. Recursively, he too can get an Attack Drone.
• Awesome, but Impractical:
  • Several weapons and base components, either due to how easily their replacements can be researched or by being Nerfed by the game mechanics.
  • The Sonic Cannon of TFTD is the biggest offender. It can firing snap shots or aimed shots and inflicts about 15% more damage than the Sonic Blasta-Rifle. However, firing a snap shot will take half of your time units, and an aimed shot requires 75%, meaning you have almost no ability to manuever. In addition, it has five fewer rounds per clip, and is so heavy you're limited in what else you can carry. The Blasta-Rifle is superior in every way except damage and, to much a lesser extent, accuracy, but since you can fire two snap shots and move with the Rifle, the slight damage increase the Cannon offers is negligible. Fortunately, the computer will use the Cannon, and all its attendant problems, exclusively about two-thirds of the way into the game.
  • The Griffon Tank in Apocalypse: Huge, has a BFG. Awesome stats for something you can get at the start... but because of a coding decision, will be destroyed if the road under it gets damaged, no matter what its current health is. Also, it's slow; flying vehicles can easily avoid it.
  • Heavy infantry-carried weapons, at least in the first two games — launchers such as the Auto-Cannon can inflict serious amounts of damage, but their weight means rookies will have problems carrying them. In general, equipping rocket launchers, auto-cannons and the like to inexperienced soldiers (which are all you've got in the early-game!) will mean they may not have enough TUs to actually fire them effectively or, not to mention, move. The Blaster Launcher is the main exception and a Game Breaker.
  • Interceptor: The Nova Bomb is this trope incarnate. Capable of snuffing out a star and its associated planets with a single shot, and destroying or killing everything in that system. That being said, it's a literal star destroyer in a game where you're supposed to be protecting the Frontier so that Earth can get the resources that are being mined from it. Blowing up those stars and planets doesn't exactly help with that mission (and each Nova Bomb is prohibitively expensive anyway).
• Awesome Personnel Carrier/Cool Plane
  • The Skyranger VTOL jet.
  • Terror from the Deep introduces the Triton, a submarine equivalent of the Skyranger.
  • The ultimate troop transports (the Avenger, Leviathan, and Annihilator) are also the ultimate fighter craft!
• BFG: The series is full of them, from the Heavy Cannon to the Rocket Launcher to the Heavy Plasma to the Blaster Launchers and their counterparts.
• Back Stab: The Rear section is one of the weakest parts of wearable Armor, naturally leading to this.
• Battle Amongst the Flames: When the battlefield is full of explosive material and/or the X-COM soldiers are equipped with incendiry ammunition, it can lead to this.
• Bee People: The Sectoids and Aquatoids are described as such. The Apocalypse aliens as well.
• Bizarre Alien Biology: Autopsy results. Some are fairly mundane, some are heavily cybernized, and some who by all means should have been dead when they were alive. ^note Many of the aliens are described as having "severely atrophied" or vestigal internal organs, suggesting that it's some other force besides biology that keeps them going. This is especially true of Ethereals, whose bodies have withered considerably since it's implied they use their psionic powers for virtually everything.
• Black Box: Even when research is done, there are still something that bugs the scientists, usually the autopsies of the more exotic aliens and miscellaneous tech. They sensibly ignore it rather than taking the (extra) time to figure it out. Shows up most often in Terror from the Deep, with the implication that the boxes are the alien connection to the molecular control network.
• Black Market: Though not explicitly stated in the games themselves, the manuals say that X-COM sold goods to buyers of questionable reputation, and when the times became rough they even stopped bothering asking about who's buying as long as they had the cash.
• Body Horror: Chryssalids, Bio-Drones, Tentaculats, several of the Apocalypse aliens, and so forth.
• Boring, but Practical: Laser pistols and rifles, which are cheap to manufacture, fairly accurate and use up no ammunition. Thanks to decent rate of fire and damage, they remain useful for entire length of game, with sole exception being Mutons. You will later find yourself dusting off your old Heavy Lasers once Sectopods come out to play.
• Boss Rush: Completing Enforcer on Xtra Spicy grants access to the XtraSpicy bonus level, where each boss in the game attacks in pairs (at the minimum).
• Bottomless Magazines
  • Only for laser weapons in the first game, the major reason they are so good. Hideously averted for everything else (see Easy Logistics below) except for aircraft and HWP energy weapons and even those just have very large magazines (100 or 255).
  • While the first game went with the "more powerful weapon = more ammo in clip" method (the plasma pistol has 15 rounds, while the heavy plasma has 35), TFTD decided that more powerful weapons need smaller clips (the Sonic Pistol has 20 rounds, the Sonic Cannon has 10).
• Brain in a Jar: The final opponent of UFO Defense, later miniaturized into an enemy unit in TFTD.
• Brainwashed: The common state of victims of Ethereals, high-ranking Sectoids, and their successors. Often, they're also crazy.
• Bullethole Door: Great for reducing the effects of drone blockage during Terror Missions. Busting through the walls of UFOs, however, will take well-placed/lucky plasma holes (interior) or Blaster Launcher shots (exterior). Or lots of plastic explosives, but that's another trope entirely.
• Character Level: The Soldier ranks are a lesser example of this, and which soldiers get promoted is out of the player's control (though OpenXcom has a mod for manual promoting) based somewhat on the performance of the soldiers and how many of them are in your employ^note The soldier promoted is based on their stats, instead of their experience, with a soldier with higher overall stats that participated in one mission getting promoted over a soldier with lower stats that participated in half a dozen missions. Functionally it's usually the same, since a soldier must not be a rookie to promoted, and soldiers that are not rookies experience stat growth, meaning that usually the deserving soldiers are promoted, but not always. For the record, every 5 soldiers gets you a Sergeant, 11 soldiers gets a Lieutenant, 21 soldiers gets a Captain, and 30 soldiers gets a Colonel (you can only have one Colonel). The higher the rank, the better the morale the soldiers have^note in theory, they also provide a bonus to lower ranking soldiers nearby, from everything from resisting mind control to accuracy to damage resistance, but functionally, the random numbers gameplay nullifies any bonuses. Getting the high ranking officer killed will also make the morale of lower ranked soldiers drop like a rock.
• Charles Atlas Superpower
  • With sufficient combat experience, a soldier can eventually beat out a tank in health, movement, accuracy, etc. Oh, and tanks can't get those nifty Psi abilities.
  • XCOMUtil's modified HWPs, on the other hand, are absolutely terrifying, and are capable of reliably hitting an enemy from a considerable distance away. And if they miss, well, that's why you use the Rocket Tanks... until you get the Fusion Ball Tanks. Which can never miss, unless you're bad at setting in the missile course.
  • Also demonstrated by Commander units on the enemy forces, particularly in X-COM and TFTD. Your average Floater, for example, dies if you so much as glare at it. Floater Commanders can take several rifle rounds to bring down, on the other hand. Rank distinctions were removed in Apocalypse, however, though enemy stats could vary greatly.
• Clone Army: Alien autopsies reveal that, with few exceptions, most of the aliens are clones.
• Les Collaborateurs: Repeated screwups in a particular funding nation or outright political manipulation thereof by the aliens can result in said nation cutting its remaining funding to X-COM and signing a nonaggression pact with the grey bastards. Most annoyingly, when you spot a UFO or USO on a "diplomatic mission", if they've landed, you're already too late. You can assault the aliens, kill every single one, loot their ship and prevent any further incursions into that particular nation's airspace, and at the end of the month be told that they've signed a non-aggression pact with the aliens. Even if the ship was only on the ground for five minutes.
• Colonized Solar System: Mars is alien HQ in UFO, colonized by humans after TFTD and is humanity's main source of elerium-115.
• Colonel Badass: The Commanders of both sides, though the actual rank of Colonel is the second highest. TFTD has the Captain and Commander as the highest and second highest ranks respectively.
• Combat Medic: Anyone with the medkit, and boy, you're gonna need them. You can also pick up a downed soldier's own medkit and use it on him, as knocked-out soldiers will instantly drop all their equipment on the ground.
• Concealment Equals Cover: Since all objects can stop at least one shot. Shame aliens tend to fire on full auto.
• Cool Starship: Completing a game often requires research and construction of an "Ultimate Craft" and interrogation for the whereabouts of an alien stronghold to drive it to.
• Cow Tools: Aliens bases and some ships are filled with these. Some you can research, some just look appropriate.
• Crapsack World: All but stated. An unknown, but likely large portion of the galaxy is ruled by an Always Chaotic Evil Hive Mind. Humans might be able to destroy the local node if they become The Unfettered — abolish every civil liberty and article of war. And there's another, unattached (albeit slightly less advanced) node in the Gulf of Mexico. And its destruction would reduce Earth's biosphere to the algae level. And there's an entire planet of Hive Mind aliens just one dimension over. And the best weapon against all these irredeemably hostile aliens are Half Human Hybrids with Psychic Powers... who will eventually become a permanent underclass treated like parolees from cradle to grave and not allowed to breed without permission (which tends to be withheld between invasions). In short, not only is The 'Verse irrefutably hostile, but it runs on From Bad to Worse.
• Critical Encumbrance Failure: Of the "carry items up to the soldier's Strength in weight, then take Time Unit and Stamina penalties for going overboard" type.
• Critical Existence Failure:
  • Averted with soldiers. Those lucky enough to survive alien gunfire (and that won't be many of the unarmored ones, mind you) will leak HP from "Fatal Wounds" to their various body parts until they fall unconscious and are either treated with a Medi-Kit or left to die. More often than not, it's the latter. Wounded troopers also suffer an accuracy penalty.
  • Played straight with Cyberdisks. Due to how 2x2 monsters work, a stunned cyberdisk is effectively a dead cyberdisk. Actually killing it results in a rather impressive boom. Which can also cause chain reactions, if other cyberdisks are close enough. The biggest problem is that the game generates the corpse first, then the explosion, which can and usually does destroy the corpse, making researching a Cyberdisc corpse a tricky proposition^note The best way to do it is to kill a Cyberdisc that's flying, specifically on the second height level or above. The corpse will drop to the ground, but the explosion will be generated at the point of death up in the sky. Fortunately, Cyberdisc autopsies aren't strictly required to progress.
  • Played straight in Terror from the Deep with Bio-Drones, which explode when killed, presenting the same problems as Cyberdiscs (with the same solution).
• Crouch and Prone: In UFO and TFTD Soldiers can crouch to improve accuracy, become a smaller target, have more cover and to allow the standing soldiers behind the crouching ones to shoot over their shoulders (though be careful, there's still a risk of hitting the guy in front of you). Soldiers automatically stand up straight when moving. Apocalypse also has a prone position.
• Cyborg / Bio-Augmentation: Most of the alien mooks are modified one way or another.

Tropes D to G

• Damage Over Time: Most attacks have a chance to cause wounds that will bleed the victim to death if left alone.
• Death from Above:
  • The Floaters and their equivalents.
  • Players can also do this once they research a means of flying.
  • Some Enforcer enemies will do this. In particular one floating buzz-saw thing likes to reach you and flip up to where you can't possibly get an angle on it, attacking all the while.
  • The best way to use the Blaster Launcher and its cousins is typically to have the round rise to the top level of the battlescape, where it will not be obstructed, navigate to the target, and then dive straight down on top of whatever hapless alien you're blowing away. This ensures a detonation; if it doesn't hit the alien, it'll hit the ground.
• Death Cry Echo:
  • Pay attention to these. Aliens only scream if they're dead. If you didn't hear a scream, they're only taking a (brief) nap.
  • The Lobstermen in Terror from the Deep are nasty, but hearing their amusing death scream^note It sounds like an irritated elephant! makes the effort of killing them worthwhile.
• Decapitated Army: In most games killing the alien leader and destroying the main base he was in makes you a winner.
  • One tactic for assaulting larger alien craft that have landed or been shot down involves blowing a hole to the bridge and killing the alien officers first. The remaining aliens tend to panic after a few turns and drop their weapons.
  • The same is unfortunately true of X-COM's forces. If the highest-ranking officer is killed, the lower ranks suffer a major morale penalty. One reason why experienced players tend to leave the Commander inside or near the dropship, where he can launch Blaster Bombs at the enemy bridge (see above).
• Deconstruction: Of children's cartoon series such as G.I. Joe and Transformers. X-COM is a team of elite soldiers who wear cool-looking armor and have a fancy Cool Ship that they travel the world in to save the world from goofy-looking aliens... and then suffer a relentlessly high fatality rate, crippling technological inferiority, and severe funding troubles. Anyone Can Die, often in rather brutal ways, and 50% or higher casualty rates are common in successful missions, with failures usually resulting in no survivors whatsoever. The cool-looking armor is good for little else besides appearance. The Cool Ship costs ludicrous amount of money to lease and is completely unarmed. The goofy-looking aliens outnumber us over a thousand to one and have technology that outstrips ours to such a degree that X-COM might as well be fighting them with sticks. The Man in Washington will happily cut funding at the drop of a hat, even if there's a UFO landing outside the White House. It is not a very pleasant situation. Ironically, after Hasbro acquired the franchise they briefly attempted to make it into a children's cartoon series, which is a rather curious decision considering X-COM's almost insanely high casualty rate.
• Destroyable Items: Repeat after me: No grenades or rockets in the alien engine room. Explosions can destroy any object lying on the ground, including corpses, unconscious units, and loot. Oddly enough, ammunition and other explosives are unaffected by explosions.
• Disadvantageous Disintegration: Someone got hit with the Blaster Bomb to the face in the room full of stuff Made of Explodium? No trace of a body and equipment.
• Disaster Dominoes: When enough units are low on morale, mistakes will start piling up and feeding on each other, until recovering from a losing battle becomes almost impossible.
• Disc-One Nuke:
  • Laser Weapons and Personal Armor, in that order: laser weapons have better accuracy and damage than the basic ballistic weapons, allowing you to kill the basic aliens (Sectoids and Floaters) with one or two shots while obviating the need for ammunition, and Personal Armor at least provides a chance for your soldiers to survive and get better at combat for the next time.
  • In Terror From The Deep, Gauss weapons aren't as much of an improvement over basic weapons that Lasers are from the first game, but Plastic Aqua-Armor, while much more difficult to get than Personal Armor^note It requires capturing a Deep One corpse, which won't show up until the first terror mission at the end of January, and also requires successfully completing the first terror mission, ends up being a huge improvement on your casualty rate, at least until Sonic Cannons and Lobstermen become more common.
  • In Interceptor, the Gatling Laser if you're good enough with it: it's not as powerful as the Standard Laser or Heavy Laser, but it shoots so much faster than either that it will chew through standard shields and basic armor plating like nothing else (providing far more damage-per-second, even with a lower damage rating). Even the Plasma Cannon, the first alien weapon you typically get in the game, can't keep up with it. You'll likely be using nothing else until the aliens start using tier 2 shields and armor, and even then, it's still an excellent weapon.
  • Through a New Game Plus or by starting a multiplayer server, the most powerful of upgrades are unlockable at the beginning on Enforcer, including the nuker.
• Doing Research: Any facility or weapon beyond the pitiful starting gear must be researched, which usually requires some alien material or corpse to reverse-engineer.
  • Oddly enough, Interceptor doesn't have you doing research. Research is completely immediately by the Galactic Science Group. What you're doing is downloading the files, the speed of which is determined by your bandwidth and the size of the files you're downloading. For some reason, you still need to have the prerequisite files on hand in order to be able to download the files that use that research (such as requiring a download of the Cold Fusion file before allowing you to download the Fusion Torpedo file).
• Doomsday Device:
  • TFTD: The sunken city of T'Leth.
  • Interceptor: The Aliens' Project Doomsday and our own Nova Bombs.
  • XCOM 2: The Avatar program, which the X-COM commander (that's you) hijacks for their own purposes.
• Drop Ship: Skyranger and Triton from UFO and TFTD respectively.
• Dude, Where's My Respect?: You're up against the outer space equivalent of the Legions of Hell, including little gray men that indulge in abduction and cattle mutilation and killer crabs that give a Face Full of Alien Wing-Wong. The Funding Nations don't really care about your situation, and sometimes consider siding with Aliens as a better alternative.
• Dungeon Bypass:
  • Tired of slogging through Cyberdisks and Sectoids while being panicked and mind-controlled? Breach the hull at the top floor and reach their Leader immediately with a Blaster Bomb! Other weapons can also breach the less-durable inner walls of UFOs, and human buildings are all too easy to destroy. A common early-game tactic is to spam rockets and autocannon grenades on buildings that aliens might be hiding in rather than engage in costly room-to-room or building-to-building combat.
  • In Apocalypse, collateral destruction is a viable strategy, if you didn't mind getting stuck with the bill. Instead of scattering troops across large, multilevel facilities to hunt down aliens in dark corners, you could set fire to or blow the floors out from under their suspected hiding places and wait for the sound of their screams. Or just level the building with combat vehicles.
• Dynamic Difficulty:
  • Regardless of the difficulty a given campaign starts at, most of the games will see fit to ramp up alien activity to correspond with consistent positive performance.
  • If the player puts off going for the Big Bad in Terror From the Deep, alien bases will start to proliferate faster than the player can keep up with them. In other words, X-COM are fighting a losing war against superior technology. If they do not exploit their weak point by finding the Big Bad, the enemy will become stronger and stronger until players have no chance of survival.
• Early Game Hell: The X-Com franchise is known for being rough on beginners.
  • In UFO Defense, the kid gloves come off about 4-5 months in, and you're expected to have your house in order. Aliens will begin dragging along Heavy Plasmas as early as month two; meanwhile, your researchers have cracked laser weapons at best. Pistols and machine guns are functionally useless by this period.
  • Your starter base is comprised of three hangars, one at each corner, with a lift in the middle. It's very elegant. In practice: the worst imaginable schematic. Good luck fending off an invasion fleet with four separate modes of entry. Expect to sink five hundred grand into demolishing and moving those helipads. It should be mentioned that OpenXCOM offers an option to design the first base from scratch. It annoyed a lot of people.
• Earth-Shattering Kaboom: Interceptor's Nova Bomb is designed to take out a star and everything orbiting it (a lower-level Class X-2 on the Apocalypse How scale).
• Easy Logistics: Averted. While ammunition for conventional weapons can be bought as long as there is money, more advanced weapons require manufactured or captured ammunition to work. And then there's allocating a limited stockpile of Elerium between manufacturing and aircraft fuel.
  • Laser weapons are considered overpowered specifically due to the fact that they don't require ammunition, such that when you have to upgrade to plasma weapons, the concept of carrying your ammunition may be entirely foreign to you. Inversely, the reason that Gauss weapons in Terror from the Deep are not nearly the Disc-One Nuke that Lasers are is because you must manufacture all your ammunition: you'll never find any from a battlefield and can't buy it, giving the second tier of weaponry a marked disadvantage.
• Elaborate Underground Base:
  • A necessity due to X-COM's covert nature, often leading to All Your Base Are Belong to Us should the aliens stumble upon it (hopefully there is more than one base built by the time an Alien Retaliation fleet comes calling).
  • Aliens have underground installations which need to be broken into to kidnap high-ranking officers for interrogation to complete the game.
• Elite Agents Above the Law: X-COM has permission to operate in more-or-less any country. So long as you do a good job of fighting off the alien forces, none of the funding nations will withdraw support. You can be given requests by these funding nations, but are not obligated to complete them. The penalty for failing (or simply not attempting) the requests is typically minimal.
• Elite Mooks:
  • Alien Squad Leaders in general.
  • Enforcer bosses, which are usually giant versions of other mooks like Reapers or Chryssalids, with special attacks.
• Emotion Bomb: "Panic Unit", the easier use of psi powers.
• Enemy-Detecting Radar: Motion Trackers, though they can only detect units that moved within the last turn. So always check the corners in case something's lurking.
• Enemy Scan: Mind probes, which allow the player to view an enemy's stats.
• The Enemy Weapons Are Better: Damage-wise at least.
• Energy Weapon: Laser and Plasma weapons. Sonic weapons are clearly energy weapons as well, just a different kind of energy, and Gauss weapons fire a form of "bullet plasma", making them qualify as well.
  • Lasers: In the first X-COM, they're extremely useful throughout the early and mid-game and retain effectiveness in the late game, as they use no ammunition. Laser pistols also have the added advantage of an very low TU cost to their autofire, making them ideal for room-to-room combat against anything short of Mutons and Snakemen missions with Chryssalids. Sectopods, the Ethereal's terror units, are more vulnerable to laser beams than plasma.
• Encyclopedia Exposita: The UFOpaedia in its various forms across the generations. Even more so the fansite of the same name. And there is more or less an online version of the in-game UFOpadias.
• Ensign Newbie: Your newly hired and unranked recruits, thanks to their randomly created stats, are potentially capable of being incredible marksmen, Made of Iron or — when you have researched a Psionic Laboratory — mindraping any alien they see into committing treasonous and suicidal acts of violence against their own side. (But more likely they're completely useless and you'll have to sack 8 out of 10 when you finally get their psi evaluations.) If you know what the limits are for a fresh recruits stats (for example, they can start with 40 to 70 time units), then you'll quickly realize that most of your recruits literally are cannon fodder, being at the bottom rung of effectiveness.
• Everything Breaks: Walls, trees, even entire buildings can be shot to pieces or just plain blown up in firefights. Even downed UFOs can be breached by blowing open the Hull or, with a lucky enough shot, can be obliterated from the inside with the Blaster Launcher. Care should be taken around vehicles, fuel pumps, and Elerium cores, as a stray shot can lead to Stuff Blowing Up.
• Exclusive Enemy Equipment: Subverting this is X-COM's specialty. There are few things the aliens have that your technicians cannot reproduce, including the alien fuel material. Everything else, up to and including their power sources, navigation and weapons can be reverse engineered, adapted and fielded within a few days or, in the case of your own flying craft, a few weeks.
• Exploding Barrels:
  • Fuel drums in your bases, gas pumps in Terror Missions, and certain UFO components all explode when shot. Frustratingly, so do Elerium pods exposed to explosions.
  • In TFTD, the normal skirmishes (USO Recovery) sometimes have what seems to be oil pumps. Also, apparently sunken aircraft's engines are Made of Explodium.
• Exposed Extraterrestrials: Sec/Aquatoids, the rest of non-terrorist TFTD aliens and all of Apocalypse ones.
• Face Full of Alien Wing-Wong:
  • Chryssalids don't necessarily use the face, but they do reproduce by forcibly implanting eggs in human hosts that burst upon death to reveal a new-born Chryssalid ready to fight..
  • Tentaculats and Brainsuckers reproduce in similar fashion in Terror from the Deep and Apocalypse, respectively.
  • Brainsuckers attach onto people's heads and empty their innards down their throats. If you're lucky, you'll be fine (your armor will protect you). If you're unlucky, you're immediately dead.
• Fake Difficulty: Terror From the Deep is probably the worst offender, but the game balance would not suffer if the standard rifle from UFO Defence were capable of reliably hitting anything a distance greater than it could be thrown.
• Fan Remake / Fan Sequel: Free ones include and are not limited to UFO2000, UFO: Alien Invasion, OpenXcom, and UFO: The Two Sides. Commercial ones include and are not limited to the UFO: After Blank series, the UFO: Extraterrestrials series, and Xenonauts.
• Fear-Induced Idiocy: In the series, friendly losses and psionic attacks can cause your soldiers to panic, causing them to take random actions on their own. When this happens, there's a good chance they'll do something tactically stupid, like running out of cover, taking extremely inaccurate shots, skipping their turn, or even committing friendly fire.
• Flaming Skulls: Skull-shaped explosions.
• Friendly Fire Proof: Averted, and with the average accuracy of X-COM soldiers, frequently painful.
• Gameplay and Story Segregation/Retcon: The manual for Interceptor states that the First (UFO) and Second (TFTD) Alien Wars lasted 3 and 6 years, respectively. In-game, you'll likely reach the limit of your research and win or lose within the first year, early second if things drag out.
• Gatling Good: The Autocannons and their successors. Regular and incendiary ammo rapidly become obsolete, but high explosive rounds remain viable throughout the game. Being able to saturate an area with high-explosive bullets never ceases being effective or awesome.
• Genre Shift: What happened to every single X-COM game after the third one.
• Geo Effects: On the Strategic scale, where you land determines what kind of terrain it will be in the battlefield. For example in TFTD landing in seas around Europe makes it very likely that the mission will take place among the Underwater Ruins, and in the very deep areas it's dark as in the night mission even during the day.
• Giant Enemy Crab:
  • The Chryssalids in UFO Defense.
  • The Lobstermen in Terror from the Deep.
• Giant Mook:
  • Many terrorist aliens.
  • The Megaspawn from Apocalypse.
  • Enforcer bosses.
  • UFO Defense gives us the Reapers and Sectopods, the former a glorified alien attack dog and the latter a heavy assault mecha. Terror from the Deep has the Xarquid, a giant nautilus, the Triscene, a dinosaur with Sonic Cannons, and the Hallucinoid, a prehistoric jellyfish with chemical freezing agents.
• Global Currency: Everything bought and sold in the main games is apparently done so in U.S. dollars.
• The Goomba: Sectoids in most continuities. In the Geoscape, the "Very Small Scout" is the UFO equivalent. In fact, the score for capturing it intact is lower than what you would get for blowing the sucker to pieces.
• Grenade Hot Potato: With a little coordination and luck, a soldier in the back can prime and pass a grenade to the front.
• The Greys: The sectoids are the classic little grey aliens with big heads. They're the weakest enemies in the game and have psionic powers.
• Grid Inventory: Multiple grids throughout the body and uniform (and multiple Time Unit costs for movement of items from location to location) make a refreshing take on the Inventory Management Puzzle. The true Inventory Management Puzzle (at least in the first game or two) was deciding what 80 pieces of gear to bring along on a mission. A fully loaded Avenger/Leviathan (holding 26 soldiers) could consume 52 of those slots just giving each soldier a gun and its ammunition. And that's without bringing extra ammo for reloading.
• Guns Akimbo: Doing this in UFO and TFTD only gave you another weapon to fire from with penalties. In Apocalypse, it greatly increases the fire rate of the soldier, but only pistol weapons can be dual-wielded. However, it only works in Real-Time mode.

Tropes H to P

• Harder Than Hard:
  • Superhuman. "Ironman" Mode saves the game after each turn, thus preventing the player from fixing mistakes.
  • Enforcer: XtraSpicy is unlocked after beating the game on hard. The most obvious difference is Numerical Hard.
• Harmless Luminescence: In X Com Enemy Unknown and its sequel XCOM 2, flashbangs will disorientate aliens and their allies, but will do nothing to your own soldiers.
• High Turnover Rate: If you're not good enough or just plain unlucky, most X-COM soldiers will not last more than a month or two, leading to this.
• Hive Mind
  • The aliens in UFO Defense take orders from one, another in Terror from the Deep tries to tell a Cosmic Horror Story while it's at it.
  • The true threat in X-COM Apocalypse are actually colonies of microscopic organisms that are sentient in groups. Every alien life form you encounter in that game is merely one they've managed to take control of and manipulate to their own ends; the "brainsucker" life form that turns your comrades against you just injects their brains with an overload of micronoids. Late in the game, some UFOs try to take control of buildings and organizations by directly sprinkling lots of micronoids onto the building in question to influence the minds of those within.
• Hoist by His Own Petard: This is a theme in all X-COM games. The aliens invade with superior technology; X-COM captures and reverse-engineers that technology; ultimately X-COM adapts and uses that technology against the invaders with great effect.
• Hold the Line:
  • The objective of any Base Defense mission. Can literally turn into Hold The Line if you choose to adopt such tactics, although in some cases it's not so much line-holding as shooting fish in a barrel with a BFG. This probably only applies if your base is attacked early in the game where aliens' psi attacks turn it into a nightmare. But, once you screened your recruits (and sack the weak-minded ones) and researched alien weapons, even if you have a poorly designed base, a defense mission is just a shooting gallery.
  • Two early missions of Enforcer. The first requires defending against incoming waves while travelling on a hover boat, and the second in the following mission where you defend four humans in a forcefield. A late mission requires you do destroy on an aircraft while defending the pilots. (Only "hold the line" missions have vulnerable civilians. In all other cases, they'll simply scream due to nearby weapon fire.)
• Hollywood Healing: Averted, wounded soldiers have to stay on lengthy medical leaves, with the most serious cases taking months.
• Hovertank: With your choice of Fusion Bomb launcher or Plasma cannon. Arguably, the Cyberdisc can be considered one of these sans turrets.
• Hub Under Attack: In most of them your land base(s) are detected by the aliens and they launch an offensive against it/them. In XCOM 2 your mobile flying base is forced down by an EMP emitter and you have to destroy the emitter while fending off waves of enemy troops trying to board you.
• Humanoid Aliens: Most of the weapon-using aliens you face are humanoid in appearance, and in some cases were human before being genetically modified. The rest, with few exceptions, are non-humanoid terrorist units that support their masters.
• Human Resources: Many research reports state that the aliens "harvest" humans for various purposes, from research to organ extraction.
• Idiosyncratic Difficulty Levels:
  • Beginner, Experienced, Veteran, Genius, Superhuman.
  • Apocalypse is a bit simpler: Novice, Easy, Medium, Hard, Superhuman.
• Immune to Bullets: Because of how armor works and damage is rolled, certain enemies are actually immune to standard rifle or pistol rounds. Some are even highly resistant to otherwise powerful alien weapons (hello, Sectopods and Lobstermen).
• Imported Alien Phlebotinum: About 75-90% of the gameplay revolves around the acquisition, understanding, and implementation of cool alien toys. Or in the RPG terms: Kill them, take their stuff, reverse-engineer it, repeat. Reversed in Apocalypse: when you sell some of your stuff to a MegaCorp that's been infiltrated by aliens, the aliens will import your phlebotinum.
• Instant 180-Degree Turn: Averted. Turning costs Time Units, though it will not trigger alien reaction fire. Sometimes, troopers who have to turn to face the enemy wind up without sufficient TUs to take the shot.
• Instant Sedation: The enemy is stunned if the stun damage exceeds the normal health. Thus, it is usually played straight for weaker aliens and those with weakness to stun damage, unless you are unlucky, but generally averted for stronger ones.
• Isometric Projection: The perspective used for Battlescape.
• Item Crafting: Manufacturing the reverse-engineered alien technology and our own creations.
• It's Up to You:
  • The world governments tried to stop the alien threat individually and failed (some had initial success, like Japan being able to shoot down a UFO, but failed to be good enough at everything to be effective). As a result, X-COM is given the best of everything from every country (people, tech, etc) and told that they're the last hope.
  • Terror from the Deep: X-COM was disbanded after the first war due to the lack of a viable threat, and went corporate. When a new alien threat emerges, the world governments turn to the company best suited to handle it: The X-COM Corporation.
• I Want Them Alive!: When researching Alien Origins and later items down the line, the reports state that you need to capture higher-ranked aliens.
• Jet Pack: Your troops get these during the late game (or from the start in case of Apocalypse). The flight-capable aliens (except for the psychic aliens who use their powers to fly) usually have these... built in.
• The Joys of Torturing Mooks: If you can survive long enough to craft blaster bombs and flying suits, breaching UFOs turns into a turkey shoot. Until then, you may content yourself with setting jungles on fire, torching UFO interiors to cook aliens from inside the shell, and levelling their sniper's nests with TNT...
• Kill It with Fire: Burning the zombies (with incendiary ammunition) will also kill the chryssalid\tentaculat without it popping out.
• Kill Streak:
  • The total number of "kills" in each soldier's profile.
  • Enforcer: The "hot streak" is increased by killing aliens, but is reduced by taking damage. As it increases, it treats weapons as being at least one level higher than the research level.
• Law Enforcement, Inc.: After the Second Alien War of TFTD, X-COM becomes this to avoid underfunding. X-COM's more ambitious cousin Marsec started out as a replacement for the former in guarding the martian colonies so that they could concentrate on potential alien threats but soon becomes a para-military corporation with a ruthless reputation. Megapol from Apocalypse, in addition to being a police force, also operates other 24-hour services, the firefighters and the hospitals.
• Lensman Arms Race: As X-COM improves their arsenal and knowledge via research and reverse-engineering, the aliens will start sending bigger UFOs with larger groups of better-trained soldiers wielding bigger guns with nastier support monsters, after which X-COM will improve their arsenal and knowledge via researching and reverse-engineering of anything this new wave had on their dead bodies. Rinse and repeat.
• Let's Split Up, Gang!: A great tactic, in movies as well as computer games! Seriously, though, bunching up your squad isn't such a good idea, either, as they tend to attract grenades^*Except in the first game, where an AI bug means that aliens will never throw grenades. You're still vulnerable to Small Launchers and Blaster Launchers, so watch out. A balance between the two is best.
• Lightning Bruiser: Mutons and especially the Lobstermen are big, strong, tough and pretty good shots with their guns and grenades.
• Lore Codex: The UFOpedia, which contains information on the enemies that you researched after capturing or killing them, as well as their ships, their weapons, their useless but interesting technology, and their society. It also contains information on your ships, weapons, items, and base facilities, making it the one-stop shop for any info you're looking for.
• Machine Monotone: Enforcer has various phrases normally said in an excited fashion, except that they're said by the Enforcer.
• Made of Explodium: Lots of objects on the battlescape will explode when shot. Special mention goes to the Cyberdisc and its successor, the Bio-Drone. When they die, they explode with stunning force, causing collateral damage. This can help for better or for worse, depending on who the explosion kills.
• Marathon Level: Two-parter missions can go on for quite a while, which may strain the player's resources.
• Mecha-Mooks: Various Terrorist aliens, most of them being mini-Flying Saucers.
• Meet the New Boss: Pretty much every new alien threat faced in the original series, when it comes down to how they act and their goals, is essentially the same product in new packaging of the original aliens: aliens want Earth, humans in the way, destroy all humans. Apocalypse throws a bit of a curve in that the interdimensional invasion is from aliens desperate to escape their dying world.
• Mercy Mode: Having a particularly bad month performance-wise or worse, a string of bad months, will make the game take pity on you by making the "X-COM agents discover the Alien Base". Technically possible even if you're doing fine, but much more common when you're doing bad^note If a base is undetected for several consecutive months, someone else does the recon for you and points it out, regardless of your score. However, if you're having a bad string of months, the game specifically spawns a base and then points it out to you to give you a chance.
• Mind Control: The harder, but much more useful, use of psi powers.
• Mind Probe: A handy tool for either side to gather information on the other. Best used for determining how close an enemy is to collapsing from stunning, or whether that alien right there is a Soldier/Medic (Mook), Engineer (useful for research), or a Commander (Boss, crucial to capture in the late game). Becomes obsolete once you get high-psi strength units equipped with psi-amps, which can take total control of an enemy and allow you to see its stats at any time for the remainder of the turn.
• Monster Compendium: Via UFOpaedia.
• Money for Nothing: UFO parts and corpses sell quite well and X-COM itself can self-finance through arms manufacturing.
• Morale Mechanic: Casualties and psychic attacks can cause your soldiers to panic, moving and shooting at random. The presence of a high-ranking officer can reduce morale loss from casualties, but an officer's death has a larger effect on morale.
• Multinational Team: You recruit from around the world. However, recruit names are exclusively drawn from Russian, French, German, Japanese, and British/American pools (the last two being a little difficult to distinguish). TFTD adds Spanish and Italian pools.
• My Brain Is Big:
  • The Sectoids and Aquatoids are small, impish humanoids with enormous heads. Certain variants have psychic powers.
  • Ethereals aren't exactly under-endowed in the grey matter department. Their design in Interceptor has a brain large enough to apparently need air-cooling.
  • The Alien Brain, which is precisely what it sounds like, and the final boss of UFO, is very big indeed.
  • The Psilords (Interceptor) are apparently all brain.
• Mythology Gag:
  • The "Gollop" chamber.
  • Marsec's first appearance was in Laser Squad, the spiritual predecessor to X-COM.
  • Enforcer features a mishmash of resources from two fellow X-COM titles scrapped during its development, Genesis and Alliance.
  • In X Com Enemy Unknown the player is shown a cutscene after researching laser and plasma weaponry, which shows a researcher test out the new gun on a cardboard cutout of a Sectoid and a Muton respectively. The depictions of the aliens, however, come from X-COM: UFO Defence. Same thing happens in XCOM 2 when you develop Magnetic and Plasma weapons, but this time the Sectoid and Muton cutouts are made using their images from XCOM: Enemy Unknown.
• N.G.O. Superpower: X-COM in a nutshell. Able to freely cross borders, intervene militarily with impunity, and dedicated to Earth's defense, rather than any particular country, X-COM is answerable only to its budget. As long as the organization maintains a positive account balance and has at least one supporting country^*and in Apocalypse, you can even ignore that requirement, it will continue to fight against the alien invasion. Justified by the desperate straits of the situation, and the funding councils are quick to pull support if they can justify it or the second the invasion seems to have been thwarted.
• No Hero Discount:
  • Your starter fleet. Until you begin building your own crafts, you're stuck leasing the hand-me-downs from Earth's military, built entirely from crap Terran technology.^*The Interceptor and Skyranger actually represent the pinnacle of available Earth technology in the XCOM universe, they're just hopelessly outmatched by alien weaponry Each one costs a half million a month, and it adds up fast. They must be insured, though, because you can completely trash them with zero penalty.
  • In general, this is played straight for any Terran gear you want to buy, and for the wages of your staff. You're expected to stay within your budget or else find alternative ways of funding your operations.
• Non-Lethal Warfare: Stun Rods (melee spears), Stun Bomb Launchers (basically a grenade launcher that fires stun bombs) and their successors. The only other way to capture aliens is to make them pass from pain from normal weaponry.
• Nothing Is Scarier: Night missions can be exceptionally creepy, especially in Terror from the Deep. It's pitch dark and there are aliens packing enough firepower to drop soldiers in one hit, and furthermore, since it's so dark, you don't know where they could be hiding. It can get even worse if you're on a Terror Mission with Snakemen, and you know that there are Chryssalids just waiting for you to screw up.
• Omnidisciplinary Scientist: The same staff of scientists does everything from reverse-engineering captured weapons to designing new aircraft to interrogating prisoners. Although considering that you NEED a lot of them to have a decent research progress, it could be handwaved that, say, a research on Plasma Weapons is led by the specialists in the field with everyone else following instructions. In Apocalypse we got three types of scientists: Engineers, Quantum physics and Biologists.
• One-Hit-Point Wonder: Your units actually have a life bar but, until they gain lots of experience or get some BETTER armor, they might as well have one hit point. This is only averted at the start of the game by the very rare occasion of a soldier surviving a Plasma/Sonic shot in their starting armor due to a low damage roll.
• One-Hit KO:
  • Chryssalid melee attack. The same goes for its successors.
  • Soldiers can be easily killed in one hit from a Plasma gun, even if he is wearing a Power Suit, if the damage roll is high enough.
  • Vibro Blades in Terror from the Deep are capable of killing most aliens in one or two hits, including the Implacable Lobstermen.
  • Interceptors in UFO Defense and Barracudas in Terror From The Deep are your initial vehicles for shooting down UFOs and USOs respectively. They have a maximum health of 100. Battleships (and Dreadnoughts in TFTD) have weapons that do 150 points of damage, and greater range than every craft weapon^*The exception is the Disruptor Launcher and the Pulse Wave Torpedo, which have the greatest possible range, but still don't have enough damage potential to shoot down a Battleship/Dreadnought alone. Curb-Stomp Battle is the only possible outcome.
• One Stat to Rule Them All: Psionic Strength in the first game (and its cousin MC Strength in the second) is the only stat that cannot be trained and it determines both resistance to alien mind control and the soldier's ability to control aliens. Actively using psionic abilities provides experience for all but three other stats.
• One-Steve Limit: Averted due to limited names pool. With only a relatively small amount of names to pick from when a new soldier is randomized, it's not uncommon to see several share a name.
• Only a Flesh Wound: Averted. Arm and leg wounds will greatly reduce a soldier's fighting ability, just like head and torso wounds. And that's on top of bleeding to death.
• Organic Technology: All sorts of purpose-bred aliens in the first two games, and practically every aspect of the alien threat in Apocalypse.
• Organization with Unlimited Funding: Zig-Zagged; the Funding Nations/Senate are huge cheapskates, but once enough engineering facilities get going and start cranking out weapons to sell, X-COM can effectively go rogue. However, the better the player does at protecting a given nation, the more they'll increase funding. As the game only ends when the player is in the red for too long or if all nations sign non-aggression pacts with the aliens, it's possible to keep protecting a few nations at a time and building up their funding over time to replace the nations that drop out. In a sufficiently long game, it's not uncommon to have the USA providing 14-20 million dollars a month to X-COM... as the only nation still funding it.
• Pacifist Run:
  • UFO and Terror From the Deep: To progress, the player needs to capture enemy aliens alive to interrogate or inspect them. Cue the player loading up on stun rods and other nonlethal equipment (depending on which installment in the franchise) so they can capture most or all aliens alive in one mission (and then get back to the slaughter once research is complete).
  • In Apocalypse if a player raids an organization without killing anybody or damaging any property, the relations aren't penalized, despite the stolen loot. Plus Apocalypse has stun grenades, ranged stunners and mind control available from the start. Many players raid Marsec for all the cool weapons not available from the start or in short supply. There are also Mind Shields, which were cut and cannot be bought.
• The Paralyzer: From Stun Rods to Stun Bombs, a variety of nonlethal arms gradually come into X-COM's possession and employ for the capture of necessary live aliens.
• People Jars: You will find these in the Alien bases. Unfortunately, they contain what left of their occupants.
• Player Headquarters: Though there is no HQ in the strict sense once you have multiple bases, the cost and time associated with building bases and the subsequent maintenance fees will make the first starter (and already developed) base your main base of operations. Which is bad, because it's the most likely base to be attacked, and has an extremely difficult-to-defend layout^*As a general rule, because of the difficulty of defending the base, it makes the most sense to cram as much base defenses into the first base as possible, especially once you know that the aliens are searching for the base. While this takes up valuable space for other facilities, that can be solved by diversifying your bases elsewhere (setting up a dedicated manufacturing base, for example). The only problem is that constantly replacing the base defenses with upgraded defenses is time-consuming, expensive, and provides periods of vulnerability while the new defenses are being set up. As a result, it's important to rush either the second or third tier defenses (laser/gauss or plasma/sonic, depending on the game) as quickly as possible so that you don't have to replace them later.
• Player Mooks: You can hire as many soldiers as you want, as long as you have the money for it. Try not to get too attached, they don't have very good life expectancy.
  • Faceless Mooks: Once you get Power Armor in UFO Defense, all of your soldiers become this.
• Powered Armor: Power Armor (and Flying Armor) in UFO Defense uses Elerium-115 to power defenses and muscle enhancers (and in the case of Flying Armor, the flight ability). Flight and robust protection are the only benefits; Power Armor has no bearing on a soldier's strength or other stats (the muscle enhancers are just fluff, since they don't affect anything directly, not even carry weight).
  • Ion Armor (and Magnetic Ion Armor) serves the same purpose in Terror From The Deep, with the added benefit of an actual strength bonus for carry weight when it is being worn.
  • Apocalypse provides Flying Armor for purchase right from the start, and provides additional armor upgrades from there. The basic Marsec Armor, however, is unpowered.
• Power Crutch: The PsiAmps and their variations that enable X-COM soldiers to use psychic powers.
• Power-Up: All powerups, whether weapon or conventional, need to be researched in order to be equipped and/or randomly dropped (in Enforcer).
• Properly Paranoid: Anyone who takes great care while handling Terror Missions. If you aren't covering all the angles, you're just Tempting Fate.
• Psychic-Assisted Suicide: Aliens won't shoot themselves, but they can be made to drop primed grenades at their own feet or drop their guns (only in the first game).
• Psychic Powers:
  • Of the telepathic kind, making victims panic (or go berserk) to controlling them.
  • The second game renamed Psi to Molecular Control, which is suitably more horror-inducing.
• Psychic Block Defense:
  • Androids in Apocalypse cannot be controlled at all, on account of being robots.
  • The protagonist of Enforcer is [[implied]] immune to mind control, considering the situations the player gets into.
  • HWPs and SWSs in UFO and Terror From the Deep. Being unmanned vehicles, mind-affecting powers do not affect them.
  • One of the novelizations has a guy who happens to have a Psi Strength of zero. It makes him unable to use psi powers at all but they don't work on him either.
  • There are only two aliens in Apocalypse that are easily affected by Psionics, them being the Anthropod and Skeletoid. All other creatures are resistant to Psionic attacks because they are either less intelligent (which somehow boosts resistance), in the case of Multiworms or Spitters, or possess Psionic abilities themselves, like the Micronoid Aggregate and Psimorph.
  • Apocalypse has Mind Shield — an item increasing psionic defense when used in the battlescape. Due to a bug the increase is permanent and cumulative, thus any operative can become invulnerable. The item was supposed to be removed completely from the game, but due to another oversight may be encountered during missions in Marsec buildings. Fans have come with an in-universe explanation that permanency and cumulation were unexpected side effects, Marsec found them disastrous for their business — killing the market both for Mind Shields and Mind Benders — and recalled all unsold items shortly before the game start.
• Purely Aesthetic Gender: Recruits can be either male or female. This has absolutely no effect on starting stats or stat growth. All it does is paste a slightly different head on the sprite and give ladies a different scream when they die. (In the second game, at least. In the first game, all aliens and all soldiers sound the same when they die.)

Tropes R to Z

• Race Against the Clock:
  • Even if your service is exemplary each month, you can't stop the funding nations from dropping out of the project. (Taking out the "Infiltrator" UFOs slows down the process, but it ultimately cannot be halted.) Lose enough donors, and you might go bankrupt. Lose all of them, and the program is shut down.
  • Averted in Apocalypse, if only because it doesn't matter if everyone hates you as long as you have funding.
  • Also technically averted in Interceptor: in theory, the aliens are constantly working towards their goal of building the Planet Destroyer to raze Earth. In practice, you can take as much time as you need, as long as you don't go bankrupt^note There is a time limit that can be extended by destroying alien Ore Processing Platforms, bases, and supply convoys, but the time limit is so generous as to be functionally meaningless anyway.
  • The Avatar Project serves as the clock in XCOM 2. When it's completed, it's replaced with an actual clock. Once that hits zero...
• Randomized Damage Attack: The weapon stats displayed in game show average damage. Guns roll from 0 to 200% of that, while explosives roll 50-150%. Lucky, unarmored soldiers can survive point-blank heavy weapons fire while unlucky, armored ones die to stray pistol rounds. TFTD adjusted it so all weapons roll 50-150%, making the above mentioned situations less common, but not impossible.
• Randomly Generated Levels: Using an algorithm to procedurally construct levels from "tiles". Just as likely to spawn your exit ramp in front of a Muton priming his grenade, alas.
• Random Number God: In addition to accuracy rolls, all weapons and explosives do a random amount of damage. A lucky soldier can survive multiple bursts from heavy weapons, whereas an unlucky one dies from an ally's missed shot. For a comprehensive, heartburn-inducing list, there is even a Murphy's Laws of X-COM.
• Realpolitik: There is a little bit of this in how the Council of Funding Nations reevaluates its funding of X-COM. Ex: X-COM performed excellently in one month, except for that time where a few particularly large UFOs flew over Country A unopposed, causing trouble, giving Country A enough reason to reduce funding. However, since the Council's majority opinion of X-COM is overwhelmingly positive that month, Country A has no choice but to stay quiet, not increasing the funding as their only means of protest. This will only generally occur if XCOM has a total score of 600 or more at the end of the month: if the score is less than 600, then the funding nations are more likely to act according to the respective UFO/XCOM activity, though the majority will still rule. However, if a country is treated terribly by XCOM (say, a terror site is ignored), then even if XCOM manages to recover enough to have the rest of the nations provide a funding increase, then the offended country will still lower their funding, realpolitik be damned.
• Real-Time Strategy: The Geoscape/Cityscape screen is real-time, pausing for events like delivery of ordered items, an alien sighting, or the arrival of troops at a mission site.
• Reconstruction: The Firaxis games are basically reconstruction of the concept deconstructed by the original series as detailed in Deconstruction:
  • High casualty rate? For justified reasons (such as how the aliens move fast in Enemy Unknown and how the aliens are taking over everything but the wilderness in XCOM 2), the XCOM fields around 4-6 operatives every operations to minimize the potential of large number of casualties. And they're trained to fight what appears to be hopeless odds stacked against them.
  • The goofy-looking aliens outnumber us over a thousand to one and have technology that outstrips ours to such a degree that X-COM might as well be fighting them with "sticks"? An intrepid science team manages to timely study the enemy and humanity eventually fight back with their technology. Which such thing happened in the original game, in the Firaxis continuity, research is generally faster, and some researchs managed to turn what seems to be a Ragtag Bunch of Misfits into The Dreaded, as The Spark and Alien Ruler based armors could passively induce fear toward the aliens.
  • The Man in Washington will happily cut funding at the drop of a hat, even if there's a UFO landing outside the White House? Humanity already acknowledge how impossible the war it seems against the aliens that they'll entrust everything to XCOM (apart from being falsely accused to house EXALT in Enemy Within), and the "cut funding" is done "happily" usually by having the government representative being mind-controlled by aliens. By XCOM 2, what remains of the free humanity are usually housed in secluded havens in the wilderness across the world.
• Red Eyes, Take Warning:
  • The Reapers in UFO.
  • The Aquatoids in Terror from the Deep.
• Red Shirt Army: At the start of the game, the player's soldiers are all ridiculously fragile, and as likely to die as to inflict any damage at all. If you arm them correctly, they may survive a shot or two. Assuming you aren't save scumming, an efficient play-through will likely burn through dozens—if not a hundred—rookies and vets by the end. This is normal, and as the weary saying goes: you don't fly to Cydonia, you climb there on a mountain of dead rookies.
• Regenerating Health: Available in Enforcer as a researchable passive ability.
• Ridiculously Fast Construction: Building a base gives you an instant lift. Other than that, the game avert this.
• Roboteching: Blaster Launchers and their equivalents with their diabolical waypoint-based targeting system.
• RPG Elements: Soldier stats in all games.
• Save Scumming: A common strategy, unless you think this is cheating or dishonorable — it is possible to win the game with 0 casualties. The game designers do make a token effort to discourage it; you can't load a saved game during a combat mission, although you can save all you want in the middle of a mission.
  • This is potentially defied by the reboot games which have an 'Ironman' option which prevents you from having more than one save file, which autosaves every turn- but, being optional, it's only for if you really want to play that way.
• Scary Dogmatic Aliens: The bad endings classifies the aliens as the Conqueror type, who attack Earth for its resources.
• Screw the Rules, I Have Money!: While X-COM is supposed to protect the whole world from the aliens, you'll quickly find that selling the extra stuff you find gives more money than the supporting nations ever can. Thus, as long as one country remains protected, you can let all the others rot.
• Secret War: All of them start as one, but according to the manuals all of them become open secrets later. The backstory in the manual for Terror From The Deep is explicitly a former high-ranked X-COM soldier being interviewed about the first alien invasion, ending with the ominous warning that he's being called back to service. He's the poor sap killed in the video intro.
• Seeing Through Another's Eyes: Through mind-control.
• Sensor Suspense: Motion detectors: a good way to avoid becoming Cannon Fodder when facing alien weapons, but since you don't know whether the blip is from alien or civilian and on which floor, dealing with the results can be... interesting. Two words: Hidden Movement.
• Settling the Frontier: The region of space in which the game takes place in Interceptor is explicitly called "The Frontier", and is stated to be a particularly resource-rich area, which is why the corporations of Earth are trying to set up resource outposts and more permanent installations. Unfortunately, it's also why the aliens are trying to set up resource outposts and more permanent installations, and why X-COM is there to fight them.
• Sequel Stagnation: Averted. After Terror from the Deep, which was basically an underwater rehash of the first episode, new elements and even Genre Shifts were introduced — unfortunately, they didn't result in good games.
• Shiny-Looking Spaceships: UFOs of the first game. X-COM fighters in Interceptor.
• Shout-Out:
  • The warp nacelles on the Avenger craft and the cylindrical Elerium reactors.
  • On the Firestorm, the primitive substitute for a UFO engine sits dead-center in the craft and bobs up and down, much like a TARDIS console.
• Smoke Shield: Caused by specialized smoke grenades and explosive terrain features.
• Sorting Algorithm of Evil:
  • In UFO Defense Floaters are the lowest threat enemies^*Though you're likely to meet Sectoids first, since they're the stereotypical "Little Gray Man", followed by Sectoids. Sectoids are one-upped by Snakemen, who are themselves outclassed by Mutons, and finally Ethereals. Psionics mess with the algorithm a bit, however^*Mutons are incredibly weak to psionic attacks, while Snakemen have a bit more resistance, swapping their positions in the sort...though you're unlikely to have psionics the first time you run into Mutons; similarly, Sectoids can use psionics, making them more of a threat than Floaters, even though Floaters are technically stronger than Sectoids.
  • In Terror From The Deep, Gillmen are the lowest threat enemies, followed by Aquatoids. Aquatoids are displaced by Lobstermen, who despite their early appearance, remain the top tier of enemy even after the Tasoth are introduced later.
  • In Interceptor, Sectoids are the least capable pilots, followed by Mutons, with Psi-Lords at the top of the list.
  • Also lampshaded in Guava Moment's Apocalypse LP.
• Splash Damage Abuse: The great vulnerability of ground-based vehicles in Apocalypse, including the tank. Also, most units take more damage from explosives that go off at their feet because of lower rated under armor.
• Sprint Meter: While Energy/Stamina is used for everything, its biggest consumer is moving around. It only partially regenerates at the start of each turn (Less when carrying heavy gear), so if an X-COM soldier moves a lot without stopping (such as when reserving Time Units for an Reaction Shot), they eventually will be too tired to move more than a few tiles.
• Star Killing: The Nova bombs in Interceptor.
• Stat Grinding: How the soldiers improve their stats.
• Stock Sound Effects: Some of the sounds that occur while navigating the menus of the original X-COM have spread far and wide across various media, recently being used in the title character's HUD in the big-budget movie Iron Man!
• Strong Flesh, Weak Steel:
  • With experience and armour, soldiers eventually gain much better stats than tanks and become more durable. However, tanks do retain a few advantages in that they cannot be stunned, mind controlled, or bleed out.
  • Inverted in Enforcer, where you will chew through Sectoids, Snakemen, and Chryssalids with one shot each while their feeble attempts to harm you bounce off your armored hull. It will give your positronic brain much amusement.
• Subsystem Damage: Head, Body, Separate Arms and Legs, with penalties one soldier's efficiency depending on injuries. Assuming the soldier in question survived the first shot.
• Super-Soldier:
  • Mutons and Lobstermen. Your soldiers will become this if they are lucky enough.
  • Enforcer's protagonist, who racks up over a hundred dead aliens a mission, and sometimes as many as four hundred fifty.
• Tactical Withdrawal: You always have the option to abort a tactical mission, and it is occasionally the best available option. Aborting a mission preserves the soldiers that are on the X-COM craft, lets you take home any artifacts they managed to recover, and keeps you from losing the X-COM craft itself^*a costly proposition, since you lose the craft and all the soldiers and gear on it, which all has to be replaced. You also have to pay to "buy" the new craft, and will be without one for 3 days. And you'll have a huge penalty to your mission score (and therefore your end-of-month score) for all the soldiers killed, the gear lost, and the special penalty for losing the X-COM craft. The downside is that the mission is considered a failure, which the funding nations will hold against you at the end of the month. The immediate consequences are also a potential concern^note Landed UFOs will take off immediately, preventing you from launching another assault and losing points for an "unintercepted UFO flight"; bases will continue to operate and will restock all their soldiers, meaning the mission isn't getting any easier; Synonium sites in Terror From The Deep disappear, which advances alien plans tremendously; and so on. The best case for aborting a mission is when you are not prepared to handle a terror mission: ignoring the mission entirely results in a -1,000 score penalty. Landing at the site and then immediately aborting only has a penalty equal to the total number of civilians killed times 30 (maximum is -360), which is far more manageable.
• Take Cover!: Very important, given the computer's cheating tendencies and the power of alien weapons. Unfortunately, most forms of cover can be destroyed.
• Tank Goodness:
  • HWPs are a refreshing alternative to the hopeless rookies in the early game, at least in Enemy Unknown.
  • Terror From the Deep: SWSes do make good scouts if you don't like sacrificing rookies for that. Once you get a Sonic Displacer, you will like it for its ability to float, get 200 shots clip which gets reloaded for free every missions, and ultimately, SWSes can't be harmed by tentaculats. If you already have the bigger ships, you will always want to bring one (or two) on every missions.
• Team Title: Subtitles aside, the series is named for the anti-alien unit commanded by the player.
• Technology Levels: Human Starter Tech < Advanced Human Tech < Alien Tech = Alien-based Human Tech.
• Tech Tree: While almost all physical alien artifacts can be researched as soon as you recover them, several conceptual lines of research require either the interrogation of live aliens or a series of prerequisites.
  • The Tech Tree in UFO Defense is generally pretty straightforward: if you capture alien alloys, you can research alien alloys, for example. However, the Tech Tree in Terror From The Deep is extremely complicated: you can't research the equivalent of alien alloys (Aqua Plastics) until you researched a Deep One Corpse^*Specifically because the Deep One is using Aqua Plastics as a type of integrated armor, prompting the study of how the plastics work, for example. Given the fact that the first game had just about every autopsy be completely optional, the sudden shift of importance to the study of corpses and interrogations, as well as the implied extra time required to do so, makes Terror From The Deep much harder as a result.
• Telepathic Spacemen: Ethereals, experienced Sectoids, their underwater cousins Aquatoids, Gill Men commanders, Tasoths, Psilords in Interceptor, the list goes on...
• Terror Hero: Your psionic soldiers can use their psi abilities on the aliens to cause them to panic, making them easier to kill or capture. They can do the same to you, distressingly. Morale is another factor as aliens are as susceptible to losing their command structure as anyone else. Taking out a boatload of aliens without a single human loss can result in the alien leader going off his nut and panicking; killing the leader first (via floating up to the bridge and blaster-bombing the living hell out of it) causes his directionless troops to scatter.
• Time Keeps On Slipping: The various incarnations of the Geoscape allow you to pass the time by anywhere from 1 second per second (slowest setting in Apocalypse) to 1 day per second (fastest setting in UFO Defense and Terror from the Deep) while you're waiting for the next alien sighting.
• Time Skip: Forty years between UFO Defense and Terror From the Deep, then forty more until Apocalypse.
  • For the remakes, XCOM 2 takes place twenty years after Enemy Unknown.
• Total Party Kill: X-COM soldiers are not the most durable of people. Bad tactical decisions (or even good tactical decisions) can result in an entire squad being wiped out quickly and without remorse.
• Trick Bomb: Smoke^*Dye in Terror From The Deep and Proximity^*Particle Disturbance in TFTD Grenades. The former are for obscuring vision, the latter are throwable mines.
  • The reboots contain even more that you can create, particularly XCOM 2 which includes grenades coming in flavours such as Incendiary, Acid, EMP, and Gas, as well as tricky devices that can be thrown out like Mimic Beacons and Battle Scanners.
• Turn-Based Tactics: The Squad-Level type during the battlescape.
• Unobtainium
  • Elerium-115, the alien element that becomes a cornerstone for advanced technology and can only be looted from downed UFOs.
  • Ununpentium has long been theorized to work that way, but currently doesn't.
  • Also, Terror from the Deep's Zrbite.
• Underwater Base: T'leth in Terror From the Deep and the unnamed base in XCOM 2.
• Unusable Enemy Equipment: Which will become usable after research.
• Unfriendly Fire and/or The Uriah Gambit: Note that the post-mission analysis does not have a spot for "X-COM Operatives Killed by X-COM Operatives." Your use of this oversight to justify friendly fire or the immediate court-martial of an alien-controlled operative will practically be a given.
• Urban Warfare: Terror missions. Most of Apocalypse.
• Videogame Caring Potential: Just try not to get attatched to your soldiers who got promoted to Sergeant or above rank.
• Videogame Cruelty Potential:
  • What happens if you make a bunch of rookies designed explicitly to be cannon fodder and/or scouts (yes, the two jobs overlap frequently). This makes for some delicious Black Comedy as you can name the unfortunate saps such names like "Coward", "Ray Charles", "Dead Man Walking" and "Meat Shield".
  • Parodied in Zero Punctuation's Halo 5 review, in which Master Chief is inexplicably disinvited from the mission to find Cortana, and Yahtzee decides the UNSC must want to "level up some of their rookes". Cut to a queue of mini-Chiefs labeled "Fadge", "Jools", "Nobby", all of them Lvl. Ones. (Master Chief is labeled "Lvl. Like a Billion.")
• The Very Definitely Final Dungeon: The various Aliens' HQs. Failing the missions results in instant Game Over:
  • Cydonia, the "Face on Mars".
  • The city of T'leth in Terror From the Deep.
  • The Temple ship in the X-Com remake.
  • Interceptor: The Star system housing the Doomsday project, hidden on the other end of the event horizon of a black hole, not only necessitating your fighter piggybacking on another carrier to get in and out, but justifying the use of the Nova Bomb.
  • The Underwater Base in XCOM 2.
• Veteran Unit: The Lucky Soldiers who survived enough battles and killed enough aliens.
• Vichy Earth:
  • Gillmen are the worst. Not only are they lousy soldiers, but they're traitors to boot. Gillmen serve no advantage from a tactical standpoint, and are only working with the aliens to reclaim the surface world, which they deserted during an extinction event sometime after the Mesozoic era.
  • Earth slowly becomes this over the course of the games if you do badly or take too long, as more and more countries submit to the aliens. Apart from Glorious Mother Russia. Fan studies of long-term games have concluded that out of the Council of Funding Nations, Russia will never be infiltrated by aliens. The newspapers will instead probably show Sectoid ambassadors' corpses nailed to the gates of Kremlin.
  • The entire plot of XCOM 2 is based on Earth having been conquered after a particularly bad playthrough of XCOM: Enemy Unknown and a puppet government installed.
• The War of Earthly Aggression: Mentioned in the backstories of Interceptor and Apocalypse.
• Weak-Willed: Some soldiers and aliens are way easier to mind-control than others. On the plus side, the aliens tend to almost exclusively target the mentally weakest soldier on the team, who can be used as an unarmed mind control magnet while the rest of team is relatively safe.
• We Come in Peace — Shoot to Kill: During peace talks with the funding nations, one or more alien battleships will appear in the stratosphere and land. Battleships also sometimes engage in infiltration missions. Unlike the smaller UFOs, they make a beeline for the nearest major city and land on top of it a la the Visitors from V. An infiltrator battleship has a 100% success rate when forging pacts.
• We Have Reserves
  • Rookies make good scouts.
  • The game mechanics actually encourages a We Have Reserves mentality. If you feed TFTD rookies to keep it happy, the game can be quite manageable... but if you've truly mastered your tactics and so almost never lose a man, you're screwed.
  • This mentality is sort of averted in Apocalypse. If you're good enough to consistently keep your squads alive in the early game, the difficulty will scale up quickly, but the aliens will be getting better weapons before better units (and an Anthropod holding a Devastator Cannon is still just an Anthropod), so if you really are that good, you can stay on top of the game all the time.
  • The death of a rookie is less damaging to a squad's morale than the death of a higher ranking agent. And if you're feeling particularly cold, the aversion of Easy Logistics makes it a lot easier, and cheaper, to send rookies in to combat with a bare minimum of equipment so that higher ranking and more skilled agents can get the good stuff.
• We Sell Everything: Played straight for most of the series. It makes one wonder what the people do with the alien artifacts you sell, especially the corpses.
• With This Herring
  • With this bunch of folks who would have failed the physical for any self-respecting military and have the reflexes of a dead fish, you must save the world.
  • The standard-issue X-COM rifle is supposedly based on the best traits of a variety of human firearms, combined into one package perfect for your work. Unfortunately, it was built by the lowest possible bidder^note It is, in fact, more accurate than any other projectile weapon in the game, but only when fired with an Aimed Shot. Since most shots will be Auto or Snap shots, the rifle suffers tremendously (as it has lower Snap Shot and Auto Shot accuracy than most other projectile weapons).
  • Played even straighter in Terror from the Deep. The standard equipment you get is worse than their UFO counterparts, and about half of them only work underwater. In this game, it reaches bang-your-head-on-the-wall levels: at first you're limited to your subs, darts guns and some harpoon launchers, since nothing you had before would work underwater. Then, you can have to fight the aliens on dry land as part of a terror mission. Why, then, must you still carry dart guns, instead of old Earth-made laser weapons, and wear a heavy submariner suit when you could have crates and crates full or armor from the first alien war? Heck, local millitias should be better armed and prepared than you at this point!
  • Despite that fact that "Starlight" night vision scopes and binoculars have been available since at least the Vietnam War and passive infrared night vision has been around since the 1980s... you're reduced to throwing flares.
  • In Apocalypse your starting weapons are a bit better, and Earth has some weapons on par with alien ones. Money is short, but you can raid the Cult of Sirius since they'll never like you anyway. But you can only buy what is available in the city stores, which get new shipments only on Mondays. You cannot buy the best weapons and equipment (flying armor, mini-launcher, plasma pistol, plasma sword, powerful vehicle computers and engines, the heaviest vehicles) until the start of the second or third week. And if you try to Zerg Rush UFOs with rocket and plasma hoverbikes, Megapol, Marsec and Solmine quickly run out of missiles and elerium to sell to you.
• Who You Gonna Call?: Type 4, international government funded organization.
• Yet Another Stupid Death: Players who are unlucky, forget to take precautions, or just play poorly, will get lots of these. Even a seasoned player will have some of these from time to time.
  • That being said, it's possible to recover from just about any supposed fail state, since the only things that will end the game immediately are losing your last base, or losing your last funding nation. Everything else can be recovered from. Maybe.
• You All Look Familiar:
  • Soldiers will have similar appearances on the inventory screen.
  • Played Straight in missions. On the map they virtually all look alike. The guys all have Guile haircuts and the women have ponytails. Ditto for civilians. (Veterans may remember the "Island of Identical Blue Bikinis" missions very well.)
• You Require More Vespene Gas:
  • Money, required to fund everything you do. Your official source is from the funding nations, who increase or decrease based on your performance. Your unofficial source is selling your spoils of war and manufactured goods on the black market.
  • Alien Equipment, with the most important of them being the Elerium, the alien power source that cannot be reproduced, only salvaged.
  • Hangars, Living Quarters and General Stores for increasing the Craft, Population and Item caps, respectfully. Similarly, having more Laboratories and Workshops will allows more Scientists and Technicians to be able to work.
• Zerg Rush
  • On a larger scale, X-COM typically has extremely high casualty rates in all three games and Zerg Rushing strategically to replace lost soldiers and interceptors is the only way to keep your head above water.
  • One-robot Zerg Rush is probably the best way to play Enforcer, as it lets you get those research points.
  • You can take down the largest UFOs in Apocalypse using the smallest flyer available, hoverbikes. They're practically impossible to hit with the right settings. Worked for the Rebels.
  • However, do not attempt to Zerg Rush a battleship with Interceptors (or Barracudas in Terror From The Deep). Yes, you can send as many as four Interceptors against the same target, and if you're lucky, you can use the Disrupter Launcher (or Pulse Wave Torpedo) to do horrendous damage to a Battleship. But holy cow, you'd better believe that the Battleship will One-Hit KO an Interceptor.

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*pew* *pop* *pew* *pop*

End Turn

HIDDEN MOVEMENT

*slither* *slither* *slither* *slither* *slither* *pit* *pat* *pit* *pat*

*BOOM*

"Aiiieeegurgle gurgle..."

THAT'S X-COM, BABY!

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