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Video Game / X-COM: UFO Defense

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Okay! So you shoot down the UFO and then land and take out the surviving aliens. I think I got thi— HOLY CRAP!!!!

X-COM: UFO Defense (known as UFO: Enemy Unknown if you're in Europe) is the first in the X-COM series of Turn-Based Tactics games, released in 1993.

The year is 1998. Strange things are afoot in our solar system. UFO sightings, previously dismissed as an urban legend, have become commonplace in the night sky. Reports of abductions and cattle mutilation spread terror throughout the population. At first, the global powers attempt to deal with this threat independently. However, after 5 fruitless months of trying to capture an alien craft, a deal is struck to merge these agencies into a global defense force: EXtraterrestrial COMbat Unit. On January 1, 1999, the U.N. council in Geneva rubber-stamps funding for the first X-COM base, with the proviso that future appropriations will be cut if the council doesn't see results—and soon. Meanwhile, members of the ruling body, skeptical of X-COM's ability to fend off the invaders, are secretly putting out feelers for peace...

It all started with Laser Squad, the first turn-based tactics game by Julian Gollop. X-COM was going to be Laser Squad 2 until Microprose suggested that an alien invasion scenario would be more exciting. The box art for the Firaxis remake, XCOM: Enemy Unknown, was designed in such a way to pay homage to the series' roots.

The original X-COM had a (barely) two-year development time, an AI programmed with a few Kb, and was designed to run on an 80386 PC. (To this day, Gollop is not sure how they did it.) The aliens progress according to their own agenda, constantly threatening funding, introducing new types of missions and ultimately building bases. The AI is designed to make the player uncertain of what's around the next corner. Worse, the game does not set any victory goals or narrative at the start. By contrast, the aliens have clearly-stated goals: destroy all X-COM bases, bankrupt X-COM, or make a number of countries leave the X-COM project. Thus, at the beginning of the game the player is fighting a losing war. It's only at the depths of the research tree that the player discovers the tools needed to turn the tide and achieve victory.

Spiritual successors and fan remakes

X-COM spawned a number of mods and remake attempts, such as UFO: Alien Invasion and UFO: Extraterrestrials, both of which are exact copies of the original. Another, Rebelstar: Tactical Command, came out on the Game Boy Advance along with Laser Squad: Nemesis (in and of itself a sequel to X-COM's own predecessor Laser Squad).

In addition, fans have produced their own X-COM-flavored games, most notably Xenonauts, UFO: Aftermath and its sequels Aftershock and Afterlight.

In 2014, an open source clone of UFO Defense (and later X-COM: Terror from the Deep) was released for playtesting. OpenXcom itself has enabled total conversions like the Warhammer 40K mod, The XCOM Files and Piratez.


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  • Abusive Precursors: The Alien Brain in UFO Defense claims that the aliens created humanity. One of the research projects theorises that the aliens seeded Earth with life to harvest.
  • The Aesthetics of Technology: The alien technology is sleek, shiny, and spotless.
  • Aggressive Negotiations: The game over cutscene in the PS1 version has the aliens gun down the human sent to sign the surrender treaty.
  • Alien Abduction: Floaters and Sectoids practice this. They even have a specialised UFO called the "Abductor".
  • Aliens Steal Cattle: One of the few straight but completely non-comedic examples. Several missions involve "Harvester" UFOs sent to meet the aliens' carnivorous needs. They are, of course, equipped with Cow Tools.
  • All There in the Manual:
    • The opening cutscene is laughably inaccurate (chainguns cutting down Mutons with ease? You wish), but the manual sheds a bit more light on X-COM and the nature of their job.
    • The instruction book suggests that the Interceptor is based on Japanese design. See "Tokyo is the Center of the Universe" below.
  • Animesque: The intro of the UFO Defense is proto-animesque (with a 90's comic book aesthetic), and the demo's list of features mentions a "popular 'Manga' look and feel to graphics." The background images for base functions and Hidden Movement retain the art style of the intro. Otherwise, the graphics are about as realistic as can be expected from a game of its age.
  • Apocalypse How — Planetary: If you fail to stop the aliens, they take over the world, destroy human civilization completely, and humanity ends up as a race of semi-intelligent mutants at best. Also, the sky burns.
  • Arbitrary Headcount Limit: A downplayed example, since the limit on how many soldiers you can take on a mission is the space physically available in the transport craft that gets them there, which is perfectly logical. However, it doesn't explain why you couldn't send multiple transport ships to a mission, or make multiple trips to drop more troops off.
  • Armor Is Useless: Played with. Armor does offer protection and increase your troops' chances of survival, but you can still be one-shot even wearing the strongest armor in the game. Theoretically it's possible for your unarmored soldier to eat a triple heavy plasma to the face since damage can roll anywhere from 0% to 200%, but you probably shouldn't hold your breath. Also, Chryssalids ignore armor completely.
  • Artificial Brilliance: This game features some of the best AI of its era, and still holds up very well by modern standards. For the most part, enemy units will not mindlessly wander into your fire. They hide in dark corners waiting to ambush you, shoot from behind cover, pop out of doorways to take a shot and the duck back out. Melee units like the Chryssalid will usually not advance in your direction unless they can make it all the way to their intended target and strike in a single turn. (One hit is all they need.)
    Julian Gollup: "Yeah, obviously when I was programming XCOM stuff we were faking intelligent. We had some very simple tricks to fake it. I talked a bit about the randomness element in XCOM and how we put it in the AI. But in actual fact, being unpredictable is a way of intelligently countering someone who's predictable. If you play poker, for example."
  • Artificial Stupidity:
    • The civilians in Terror Sites. They will run through a door, back through it, then back again! That is if they are not running into the middle of fire fights, because the natural place to stand in a military operation is directly in front of the man with the laser rifle. At best the civilians in Terror missions just wander around aimlessly and pay no heed to the numerous aliens in the process of mowing them down. Just do yourself a favor and stun-rod any civilian you come across. They can't wander in front of your gun muzzle, and they can't get impregnated by space bugs; just zap them in the butthole and be done.
    • It's also not uncommon to see aliens blowing themselves up with their own blaster launchers or grenades. Of course, this can easily happen to your troops as well, especially if you forget where you placed your proximity mines.
    • Sometimes a Chryssalid might run past one of your soldiers and just end its turn. This is because they prefer to perform their insta-kill attack on your soldiers from behind, even though they could easily hit your soldier in the face with no chance of failure. As a result, they run out of Time Units to actually perform the attack in that turn and end up a sitting duck for your troops.
    • Why storm the UFO when you can just clean up the area outside the UFO and then camp out at the entrance until around turn 20? Then the AI logic guiding behavior of alien characters causes them to go on the offensive... right into your firing squad. For best results, throw a smoke grenade to prevent the aliens from shooting your guys.
  • Astral Finale: You fly to Mars to assault the Aliens' HQ, the Cydonia base.
  • BFG: Anything in the heavy weapons category counts, ranging from heavy cannons and autocannons to heavy laser and plasmas. And, of course, there's the Blaster Launcher, which can devastate a large area and bring down buildings with one shot.
  • Big "NO!": A rare written example. The alien brain tries to talk you out of killing it via a computer screen at its base. The screen displays an enormous-font "NO" as the brain is incinerated.
  • Black Cloak: The Ethereals, though the cloak isn't black. A brown cloak and hood is the last thing a number of poor saps will ever see.
  • Boring, but Practical:
    • Laser Weapons: They are significantly outclassed by alien weaponry, but they still have moderate stats and most importantly they don't require ammunition to use. This makes them useful throughout the entire game.
    • Interceptors: While not as durable or fast as alien fighters, they run on conventional fuel, enabling you to save your precious elerium that would be burned up by the more advanced alien craft. Their high fuel capacity enables them to track alien ships for a long time so you can see where they land, and their damage is repaired at a much faster rate than your ships built with alien technology. Furthermore, once you equip them with plasma cannons, they will be able to easily shoot down all alien craft other than a battleship. As such, Interceptors never become obsolete.
    • Skyranger: While it's unarmed and has a much lower capacity than the Avenger, it still has some advantages that make it worthwhile till the end. It runs on conventional fuel rather then elerium, and its massive fuel capacity gives it a very long range. Unlike the Avenger, it can track a target for a long time waiting for it to land or hover in place waiting for daylight to start a mission.
    • Sitting in smoke and waiting for aliens to come out their ship before annihilating them. Unfair? Probably. Effective? Absolutely.
  • Brain Monster: The first game also features the Alien Brain on Mars as the Big Bad.
  • Briefcase Full of Money: A picture of a high-ranking X-COM agent with one of these and silhouettes of obviously armed guards behind him is the background on the screens for the buying/selling of armaments and hiring/sacking of personnel. Merchants of death don't accept charge cards, it seems.
  • Combat Pragmatist: Aliens generally qualify, and the player needs to be one as well, especially early on when fighting against a far superior opponent.
    • Aliens have no qualms about setting up in a half circle around your craft's ramp and mowing down your troops as you disembark, or hiding in structures and shooting your soldiers as you go through the door.
    • Aliens have superior night vision and can see much further than humans, and are very happy to cut you down from the cover of darkness. Unfortunately, XCOM doesn't seem to have heard of night vision goggles.
    • Psionic aliens are more than happy to mind control your troops and let them wreck havoc while they sit in safety far away. Once you have unlocked psionics, this is a good strategy to emulate.
    • One of the most effective tactics is to send a scout forwards to spot enemies, then retreat while your soldiers sitting in smoke or at a safe distance let loose while aliens can't retaliate.
    • On terror missions, aliens try to use civilians as human shields preventing the player from using powerful weapons due to collateral damage. However, a player would be wise to be ruthless here; in all likelihood those civilians are dying either way. If you have unlocked psionics, civilians make decent scouts.
    • Booby trapping choke points on the map with proximity grenades can be very effective, especially on base invasions. Booby trapping your fallen soldiers also works well, by having them carry armed explosives. Just make sure they don't die and drop it on top of you.
    • If you wait a sufficient amount of time (over 20 turns), aliens will magically know your position and start rushing you, allowing you to turn their own ambush tactics against them.
    • Throwing some rookie soldiers on a suicidal charge to capture a valuable enemy or gather vital intel on map layouts and enemy positions can often make the difference between heavy losses and victory. They know what they signed up for!
  • Commanding Coolness: Commander is the highest rank that can be attained within X-COM. A Commander accompanying your troops on a mission will provide some hefty morale boosts, but it also incurs a severe morale penalty when he/she is killed. Fortunately, the Commander's morale bonus applies to all soldiers no matter where he is on the map, meaning it's a perfectly viable strategy to simply leave him safely in the skyranger and let the other troops reap the benefit of his passive morale bonus while they carry out the mission. When you have thirty soldiers or more (combined from all bases), and a vacant position, then the best eligible Colonel is promoted. There Can Be Only One....commander at a time.
  • The Computer Is a Cheating Bastard:
    • Most prevalent in UFO Defense, where aliens don't suffer from Fatal Wounds unless they were inflicted under previous mind control, magically know the entire map (and your soldiers' positions) after Turn 20, and can target any of your soldiers as soon as just one is in visual range (particularly rage-inducing with Ethereals' psi-spamming). Even so, it's possible to fool them by bringing a psi-decoy with low mental defences and no weapons to suck up all their psychic powers, as they are always going to target the people with the weakest minds.
    • Night missions severely reduce your visibility, but have no effect on the aliens at all, enabling them to easily gun your troops down from outside their visual range. This can be somewhat mitigated by bringing flares, but they add an even bigger burden to the Skyranger's 75-item limit, their light range is limited, and you have to waste a lot of time units constantly picking them up and throwing them, to say nothing of how much this slows the pace of the game down. Generally it's better just to avoid night missions, but sometimes the timing of terror missions will require you to run them at night or else take a huge score penalty.
    • Terror missions will routinely start with aliens completely surrounding you, enabling them to easily gun down troops with reaction shots the moment they step off the skyranger. Even more infuriating is that the AI has an annoying habit of putting your highest ranking troops at the front of the line in the transport, forcing them to get off first and walk right into enemy fire.
    • If you kill the last surviving alien in a level while one of your troops is under the influence of alien mind control, that soldier will be considered "missing in action" and counted the same as if they were dead, even though they should be perfectly fine.
  • Covers Always Lie: The European cover art depicts insect-like aliens which do not appear in the actual game.
  • Crazy-Prepared: Nearly any plausible and successful playthrough revolves around the player capturing alien technology, reverse-engineering it, and wielding it to defeat the alien invasion. However the aliens actually planned for this possibility. All of their technology depends on limited supplies of Elerium, which can't be synthesized anywhere in the Solar system. All of the aliens you fight were vat-grown on Cydonia and don't know anything about the origins of the invasion. All of this means that X-Com's victory killed the only being that had any clue why the invasion happened and gained technology that depends on something they'll run out of in a few years.
  • Cutscene Power to the Max: Inverted. The opening animation of UFO Defense features troops facing down Mutons with Personal Armor, a couple of the beginning rifles, and an Auto-Cannon, which in the actual game are nearly useless against the Muton heavy armor. By the time you normally face Mutons, however, you'll be trampling them with Powered and Flying Suit-equipped soldiers packing any combination of Psi-Amps, Laser Rifles, Heavy Plasmas, or Blaster Launchers. Played straight in that you will get your ass kicked. Also, amusingly, in that you will never see a red-suited Muton in the game; the Muton Commander seen in the opening does not exist ingame. Mutons have no commanders.
  • Disc-One Nuke: If you're able to get your hands on psionics, Heavy Plasma, or a Blaster Launcher early on in the game, this gives you a huge boost. The downside is that to unlock these you'll have to capture these weapons / enemies on a terror mission or base invasion, which is easier said than done when you don't have good weapons to begin with.
  • Drone of Dread: The battlescape soundtrack is a constant, low, pulsing drone.
  • Dual Wielding: You can dual wield weapons and equipment, but if it's designed for both hands you'll suffer an accuracy penalty. This is usually best done with two different weapons such as a Heavy Plasma / Blaster Launcher / Psi Amp, though in specific circumstances you could dual-wield rocket launchers to get two shots off in a round.
  • Early Game Hell: The opening stages of the game are absolutely brutal- you only have a single base, giving you minimal global coverage, meaning it can be many in-game days or even weeks till you spot a UFO. Research and production are painfully slow until you invest in more scientists and engineers, the average rookie literally could not hit the broad side of a barn if they were inside the barn, and the fact that they go to battle wearing a pair of natty overalls while even the Sectoids that function as the starter enemies are toting heavy plasma guns means that any hit will 9 times out of 10 be an instant kill, making training them up into an effective fighting force akin to trying to paddle a kayak up a waterfall. Furthermore, new players will not know which research to prioritize or the most efficient means to fight each specific enemy type. Once you get higher-ranked soldiers with better accuracy, powered armor, and can use heavy plasma yourself, things start getting a bit easier. And once you have laser weapons, you at least begin to have some sort of chance.
    • Just how bad can this be? On harder difficulties it's possible to have your first mission as a base invasion. Enjoy starting a new game!
    • What makes the game especially hard here is that you'll often get access to equipment or be able to mitigate threats after the point it would be most useful to be able to do so. For example, once you have many bases with hyperwave decoders to detect UFOs all over the globe, you can shoot down ships trying to carry out terror missions and avoid them entirely. This isn't a bad thing, but by this point you'll probably have good enough equipment and soldiers to make terror missions fairly manageable, whereas being able to avoid them in the early game when you have rookie soldiers with conventional weapons would be extremely helpful. The Avenger is great for its speed and for the extra capacity, but being able to take 12 extra troops or several tanks would be most useful early on in the game when you'll take horrendous losses. Instead you'll get it later in the game, when you have skilled and well geared soldiers, and have much less need for the capacity increase. Flying suits nullify chryssalids which is always helpful, but by this point you should have much better weaponry to take them out, and much more accurate soldiers. All in all, this is why the game gets a lot easier once you push past the initial stages.
  • Easy Logistics:
    • There's no need to stock fuel for conventional craft as it will be automatically purchased.
    • Oddly, after completing a mission captured items arrive at the base instantly, even if your troops that captured them are still flying back with them in their hands!
    • When manufacturing certain items, you don't need to worry about having raw materials, only enough money to make them. A lot of the more advanced equipment does require you to have the raw materials, however.
  • Enemy Scan: The Mind Probe. Comes in handy to find Leaders or Commanders.
  • Faceless Goons: What your soldiers become when wearing power armor. A mod exists which makes it that they are holding their helmets in their hand in the inventory screen, like in TFTD.
  • Fantastic Drug: Sort of. Some UFOs have weird rooms with walls that look like they're covered by shifting blue or orange clouds and have strange silver orbs with red cores. These rooms are revealed to be a form of alien entertainment that stimulate certain sensory regions of the brain. They are described as being similar to hallucinogenic drugs.
  • Flying Saucer
    • One of the smaller alien craft in the first game take this form, as does the first two X-COM-built craft.
    • The Cyberdisc is essentially a miniaturized flying saucer with a powerful plasma cannon and self-destruct mechanism.
    • The hovertanks appear to be based off the Cyberdisc design. As in, they just look like repainted Cyberdiscs with a tank cannon mounted on top.
    • Essentially every UFO is a variation of a Flying Saucer.
  • Form-Fitting Wardrobe: Personal "Armor" looks suspiciously like purple superhero attire. Mutons also get emerald-tinged armor which fits them like a glove.
  • Giant Mook: Reapers and Sectopods are the size of XCOM battle tanks, and just as deadly if you are not careful.
  • Gotta Kill Them All: Missions don't end until every martian is on the floor. Annoying when you've stunned one inadvertently: they'll get up and go for a wander after a while, leaving you to wonder why the mission's not ended after clearing out the UFO.
  • Guide Dang It!: A misprint in the Encyclopedia Exposita entry for Sectopods means their primary weapon counts as a laser attack (which they're weak to) rather than a plasma attack. Combine that with the fact that 2x2 enemies have to be mind-controlled one block at a time and that blocks controlled by opposing sides can fire on one another... Controlling part of a Cyberdisk or Sectopod is, in fact, the easiest way to destroy one.
  • Gunboat Diplomacy: Supposedly why Alien Infiltration missions are carried out by Battleships.
  • Heavily Armored Mook: Mutons are extremely well armored and durable. Even with heavy Plasma, it often takes multiple shots to kill them.
  • Hold the Line: The entire game is essentially a fight to hold the line against the aliens. Every UFO you ground and every base you raid serves only to delay the aliens' eventual victory, buying you time to research a way to launch an invasion of the aliens' homeworld. Otherwise, you will only be fighting a war of attrition, and the aliens have time on their side.
  • Imperial Stormtrooper Marksmanship Academy: Inverted. Aliens tend to be pretty accurate, whereas your soldiers, especially new recruits, are capable of missing from point-blank range. Just how bad your team can be almost has to be seen to be believed.
  • Infinity -1 Sword: Heavy Plasmas aren't the most damaging in the game, but come fairly close. They're lightweight, accurate even when fired one-handed, common later on on the game, and do incredible damage to most enemies, one-shotting many aliens.
  • "Instant Death" Radius: Alien blaster launchers have enough explosive power to wipe out a city block, and will usually kill anyone anywhere within its blast zone, no matter how well armored they are. If you see an alien armed with one, pretty much your only hope for survival is being able to kill him before the end of the turn.
  • It's a Wonderful Failure: In the PS1 version, the aliens agree to a cease-fire, ram a treaty down the U.N.'s throat, then cap the President in the head before the ink is even dry. The PC version recounts the genocide of Earth's culture and people as it becomes a colony of an ancient space empire, while all of your discoveries—and, thus, any hope of future resistance—are lost forever, with the survivors mutated and sent to slave camps.
  • Jet Pack: Flying Armour is basically Energy Armour with slightly buffed stats and a jetpack strapped to it. Its flight ability allows X-COM operatives to take to the air to gain a high ground advantage against the aliens.
  • Level Grinding: It's not required to win, but doing this, especially with psionics once you can mind control and disarm aliens, quickly leads to game-breaking levels of destruction by allowing you to mind control anything, or pick opponents off with pinpoint accuracy from the other side of the battlefield.
  • Linear Warriors, Quadratic Wizards:
    • Psionic troops start out barely being able to affect even the weakest minded enemies at point blank distance regardless of psionic power, but this quickly grows until you're effortlessly mind controlling the strongest enemies from across the map with 100% success.
    • This also applies to a degree with reaction fire. Due to the game mechanics, if a soldier has low reactions then they'll pretty much never fire a reaction shot, and therefore have no chance to ever improve. At high levels you can regularly make them, which then increases your reactions further and leads to even more reaction shots, to the point that any enemy that shows their face is going to get cut down by a hail of fire before they can do anything.
  • Master of None: The Lightning. It can intercept and carry troops, but is a worse fighter than the Firestorm and a worse troop bus than the Skyranger. Contrast the Avenger, a true Jack of All Stats.
  • Mind Rape: Psychic aliens, such as Sectoids, can wreak havoc on your troops' morale. Expect to see rookies suffer panic attacks or even come under alien control at times. With psionics, you can also return the favour.
  • Mini-Mecha: The Sectopods, the heavily armored bipedal chicken-legged robot that serves as the terrorist unit for Ethereals.
  • Misidentified Weapons: The in-game ufopedia calls the Rifle a "sniper rifle". Between its relatively low damage and autofire capability it's obviously meant to be some kind of assault rifle or carbine.
  • Mook Lieutenant: Enemy leaders will show up on certain missions. They are quite a pain to deal with, as they are often equipped with blaster launchers, and sectoid leaders have the ability to use mind control. Capturing one alive is necessary to unlock the last level.
  • Mook Commander: Enemy Commanders are well armored, highly durable, and armed with blaster launchers that can easily wipe out your whole team with a single shot. To make matters worse, unlocking the last level requires capturing one of them alive.
  • Mother Russia Makes You Strong: Alien threat? No sweat — Russia is the only nation in the game that can never be subjugated by the aliens, no matter how bad things get. They'll fight until the last man falls.

  • Never Trust a Title: Alien medics don't actually perform the role of a medic in the game. They don't heal other aliens and are basically no different from regular soldiers, although they are more likely to carry stun launchers.
  • Next Sunday A.D.: The original game was released in 1993 and set in 1999.
  • Nintendo Hard:
    • X-COM: UFO Defense and X-COM: Terror From the Deep are infamously difficult even on the beginner difficulty level, as the game system is very complex, and almost every random variable in the game has a high variance in either direction. No punches are pulled early in the game, with most every enemy type capable of appearing in missions from the get-go, and at no point does a soldier ever become safe from being instantly killed by a stray shot. Even the safest move is a gamble for both sides, although the aliens aren't bothered by losses. In Terror From the Deep, because the (then unknown) bug in UFO Defense locking the difficulty to Beginner prompted the fans to complain about it being too easy, the developers made the Beginner setting of Terror from the Deep as hard as the Superhuman of UFO. There's a common rumour that TFTD had the original's bug backwards, locking difficulty to Superhuman. It doesn't; it's just a lot harder.
    • The way the game generates missions and is also utterly unforgiving. A far cry from today's games that insist on giving you a shallow learning curves and holding your hand through the most simple of tasks, X-COM has no scruples against sending you on a terror mission with nearly bullet-proof Cyberdisks or Chryssalids in the early game, or positioning aliens in a half-circle around your Skyranger's disembarking ramp, ready to mow down whoever tries to disembark. Know when to fight and when to attempt a frantic Tactical Withdrawal.
    • Since they couldn't replicate the original Alien AI with the modern code, OpenXcom developers had to make it smarter than in the original just so it would not be curbstomped, and there is a Sneaky AI option that makes it even harder.
  • Nothing Is Scarier: The combination of Night-time Missions and the Battlescape music is one of the perfect recipes for fear.
  • Novelization: Has had at least two: One by Diane Duane and one by Russian sci-fi author Vladimir Vasilyev.
  • Player-Guided Missile: The Blaster Launcher's Blaster Bombs require the player to input waypoints in order to reach their target. It's quite possible to launch a Blaster Bomb from inside the Skyranger and hit a downed UFO's Elerium reactor and kill everyone on board.
  • Player Nudge: Capturing any live Ethereal, regardless of rank, will bequeath a psionic research discovery. On Easy mode, at least, Ethereals start appearing as ground troops in June. You might even spot a Very Small Scout piloted by only one(!) Ethereal, making them that easier to catch. The other way to learn Psi was to snatch a Sectoid Leader, which was hardly guaranteed given that they rarely appear. By Autumn, the game is telling the player that they'd better hustle and learn psionics if they want to survive Cydonia.
  • Point of No Continues: "Cydonia Or Bust!" You only get one shot at the Mars Offensive. If you lose, it's an automatic game over, regardless of whether you have the resources to build another ship. Perhaps the U.N. pulls the plug on X-COM at that point. Or the aliens panic since you can attack their home base, and nuke the earth.
  • Power Armor: Energy Armour is powered by an Elerium-115 cell and provides a much needed boost to an X-COM soldier's protection. There's also Flying Armour, which is the same, but with slightly better stats and a Jet Pack.
  • Power Floats: Unlike Floaters, whose bodies are 50% comprised of levitation technology, Ethereals seem to float by their own power.
  • Power Pincers: The Chrysallids have them, used to hold their victims for zombification.
  • Psychic-Assisted Suicide: You can be the victim of this if your troops get mind controlled, especially anyone with an explosive weapon. You can turn the tables by researching psionics, and cause enemies to murder each other, blow themselves up with grenades, or fire Blaster Bombs on themselves and their friends.
  • Psychic Powers: High-Level Sectoids and all Ethereals possess these, typically used for Mind Rape. With some research, you can do the same.
  • Pyrrhic Victory:
    • Retroactively added in the Apocalypse manual, which stated that soon after the victory on Cydonia, the world goes into a political and economical chaos while X-COM is all but disgracefully disbanded.
    • Most missions, especially early on, end in this at best as you will inevitably take losses until you get your hands on better soldiers and more advanced tech.
  • Random Number God:
    • Being able to place effective fire when you need it and not getting hit by the aliens really adds to the difficulty of the game.
    • Recruitment is another issue that you have to gamble with as soldier stats are randomly generated. A good word of advice: Soldiers that don't have at least 40 bravery will go berserk and panic much sooner when the situation gets bad.
  • Rank Scales with Asskicking:
    • Blaster Launchers, a.k.a. the portable airstrike, are usually carried by Commanders, Leaders and Engineers. They have no qualms about firing them indoors, or even at point-blank range. This makes them very difficult to capture. Leaders/Commanders tend also to have better armor, speed, and reactions than your troops; in a quick-draw duel, a Commander can plug two agents and still have time to duck out through the door.
    • Sectoid leaders, but only in the first two games. Apart from selling their carcasses, most rank-and-file soldiers aren't particularly useful; the higher up the command structure you go, the more valuable the intel. Of particular note is the Sectoid navigator, who can help you construct a better radar system. A Sectoid leader can teach you psionics.
    • Not necessarily true with human soldiers, depending on whether the player has the officers on the battlefield getting exercise along with the other soldiers or leaves their muscles to atrophy in the back of the Skyranger.
  • Rare Random Drop: Technically, every alien UFO that you assault runs on a supply of Elerium, with each power source containing a stack of 50, which means that you should, in theory, get all kinds of Elerium from all the UFOs you're shooting down. But since you are firing explosive weapons at a ship that then crashes, meaning that nine times out of ten, the power source, and its associated Elerium, will be destroyed long before you touch down. Even if they aren't, a stray bullet from the weakest weapon in the game can destroy the power source in battle, taking the Elerium with it. Landed UFOs are therefore highly sought, and should be carefully attacked, in order to maximize your Elerium theft.
  • Robo Teching: The blaster launcher is a missile launcher that sends it payload to a series of player defined waypoints, making any absurd trajectory possible. However, since the missile can't hit its waypoints with perfect accuracy, the most effective way to use it is to set a waypoint twenty feet above an enemy's head, then another waypoint directly on the enemy, causing the missile to arc over the target, then slam down, ensuring it will explode even if it misses.
  • Shout-Out: The Chryssalids are based around the mutant that appears on the old Penguin cover art for John Wyndham's similarly named novel (though not in the novel itself).
  • Shut Up, Hannibal!: UFO Defense's ending, due to you shooting the brain as a result of its We Can Rule Together speech.
  • Sinister Silhouettes:
    • The bodyguards in the Buy/Sell, Hire/Sack screen.
    • On the Battlescape, sometimes enemies can be visible to your units but still in an area of the map that is unexplored, resulting in this.
  • Slasher Smile:
    • The Chryssalids have one permanently. Fitting, really.
    • Snakemen have a big toothy grin as well, but then again, they don't have any visible lips.
  • Slippy-Slidey Ice World: Arctic and Antarctic missions, thankfully without the slippy slidey part.
  • Squishy Wizard: Ethereals' bodies have atrophied so much that their self-sustaining functions have to be governed by their immense Psychic Powers. Which does not prevent them from having the best armour values and second best hit point totals among the non-terror unit aliens. Their huge cloaks present a considerably larger profile than their actual bodies... hitting the cloak is not necessarily hitting the Ethereal. Plus, there isn't much to damage in their bodies. However, their brains still need an ample supply of blood, and if they lose too much blood because of serious injuries, they die.
  • There Was a Door: One of the more effective tactics, especially when you get access to the heavy plasma, flying suit, and blaster launcher, is to smash through obstacles instead of going through doors, which have a nasty habit of leading to ambushes. The blaster launcher in particular is powerful enough to punch through a UFO's hull, opening up many tactical options.
  • Timed Mission: Technically, it is possible to extend a game into going forever but because the Aliens are actively trying to get each member of the Council to sign a pact, they can and will inevitably still win through diplomatic subterfuge, regardless of how many military losses you inflict on them. Because of that, you have to get to Mars now or never.
  • Too Awesome to Use: The Firestorm ship can both outrun and outfight any alien UFO, but the problem is it uses up Elerium as fuel, it has a very limited fuel capacity, and damage takes an extremely long time to repair. As such, it's only worth using to take down Battleships or ships that are too far away for an interceptor to catch. An interceptor armed with plasma cannons is far more efficient for taking down all other craft.
  • Tokyo Is the Center of the Universe: In the MicroProse continuity, Japan was the first country to assemble an anti-UFO force, dubbed the "Kiryu-Kai". It was eventually folded into the other agencies controlled by member nations.
  • Trailers Always Lie: There are several details that make the Intro very misleading.
    1. You will never see that cool-looking Dropship in the game.
    2. You will never see that red-suited Muton commander in the game, either.
    3. You don't get Personal Armor right away.
    4. Personal Armour doesn't allow your men to attack from the air.
    5. Rifles and Auto-Cannons are hopelessly useless against Mutons.
    6. Aliens never flee the battlefield.
  • The Very Definitely Final Dungeon: The aliens' Martian base located in the Cydonia region.
  • War Was Beginning: The opening cinematic — though the game properly starts before the war has escalated to that level.
  • We Can Rule Together: The brain offers this in the ending cutscene, but you shoot it.
  • We Have Reserves: Players are encouraged to take this approach when it comes to their soldiers. Recruits are the cheapest personnel to hire in comparison to engineers and scientists ($40,000 with a $20K monthly salary), and the average lifespan of a freshly minted soldier means you can expect a lot of turnover.
    • Certain ranks of aliens are incredibly valuable to capture alive for powerful technologies; it's well worth throwing a few rookie soldiers at an alien to capture him and unlock psionics or the Hyperwave Decoder.
    • Psionics allows you to mind control enemy units turning them into cannon fodder. If they get cut down by their friends, not only do you know where enemies are hiding, but it's one less alien you need to kill.
  • Weaksauce Weakness: Chryssalids are a complete terror in the earliest parts of the game, with 120+ action points and the ability to shred your soldiers in a few attacks and use the corpses to spawn more Chryssalids... and then you get Flying Armor. Suddenly, the dread Chryssalids and their claws are reduced to targets, as your troops can hover outside their range and pelt them with plasma.
  • Weird World, Weird Food: The "Alien Food" is a nutrient soup made from body parts extracted from cattle and humans. You can even sell it on the market.
  • You Have Researched Breathing:
    • Most research items are fairly reasonable, but for some reason X-COM has never heard of a med kit or battlefield medicine. This would be justified if this was to learn how to deal with wounds and complications caused by alien technology, but even regular bullet wounds, smoke, fire, etc. can't be treated until you do research first - many of these being covered by basic first aid that every real world combat soldier is taught in training.
    • Researching alien weapons isn't enough to be able to use them; you also have to research the weapon's ammunition magazines separately, as if the world's greatest soldiers and scientists can't figure out how to insert a magazine into a gun with simple common sense.
  • Zombie Apocalypse: Any Snakeman terror mission can turn into this if not properly managed, due to those damned Chryssalids. Every civilian or trooper is a potential zombie, and zombies are the larval stage of new Chryssalids.

Alternative Title(s): UFO Enemy Unknown