UFO: Enemy Unknown

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UFO: Enemy Unknown
X-COM - UFO Defense Coverart.png
European cover art
Developer(s) Mythos Games
Publisher(s) MicroProse
Producer(s) Tim Roberts
Designer(s) Julian Gollop
Nick Gollop
Programmer(s) Julian Gollop
Nick Gollop
Artist(s) Julian Gollop
John Reitze
Martin Smillie
Composer(s) John Broomhall
Series X-COM
Platform(s) MS-DOS, Amiga, CD32, PlayStation, Windows
Genre(s) Strategy, turn-based tactics
Mode(s) Single-player

UFO: Enemy Unknown (marketed as X-COM: UFO Defense in North America) is a science fiction strategy video game developed by Mythos Games and MicroProse. It was published by MicroProse in 1994 for MS-DOS and Amiga computers and the Amiga CD32 console, and in 1995 for the PlayStation. Its European PlayStation release is titled X-COM: Enemy Unknown.

Science fiction Genre of speculative fiction

Science fiction is a genre of speculative fiction that has been called the "literature of ideas". It typically deals with imaginative and futuristic concepts such as advanced science and technology, time travel, parallel universes, fictional worlds, space exploration, and extraterrestrial life. It often explores the potential consequences of scientific innovations.

A strategy video game is a video game that focuses on skillful thinking and planning to achieve victory. It emphasizes strategic, tactical, and sometimes logistical challenges. Many games also offer economic challenges and exploration. They are generally categorized into four sub-types, depending on whether the game is turn-based or real-time, and whether the game focuses on strategy or tactics.

Mythos Games

Mythos Games was a British video game developer company founded by Julian Gollop with his brother Nick in 1988 as Target Games. It is best known for its 1994 strategy game UFO: Enemy Unknown. Following the closing of Mythos Games in 2001, Gollop founded Codo Technologies.


Originally planned by Julian Gollop as a sequel to Mythos Games' 1988 Laser Squad , the game mixes real-time management simulation with turn-based tactics. The player takes the role of commander of X-COM – an international paramilitary organization secretly defending Earth from an alien invasion. Through the game, the player is tasked with issuing orders to individual X-COM troops in a series of turn-based tactical missions. At strategic scale, the player directs the research and development of new technologies, builds and expands X-COM's bases, manages the organization's finances and personnel, and monitors and responds to UFO activity.

Julian Gollop British video game designer

Julian Gollop is a British video game designer and producer specializing in strategy games, who has founded and led Mythos Games, Codo Technologies and Snapshot Games. He is known best as the "man who gave birth to the X-COM franchise."

<i>Laser Squad</i> video game

Laser Squad is a turn-based tactics video game, originally released for the ZX Spectrum and later for the Commodore 64, Amstrad CPC, MSX, Amiga and Atari ST and PC computers between 1988 and 1992. It was designed by Julian Gollop and his team at Target Games and published by Blade Software, expanding on the ideas applied in their previous Rebelstar series of games.

Construction and management simulation (CMS) is a type of simulation game in which players build, expand or manage fictional communities or projects with limited resources. Strategy video games sometimes incorporate CMS aspects into their game economy, as players must manage resources while expanding their project. But pure CMS games differ from strategy games in that "the player's goal is not to defeat an enemy, but to build something within the context of an ongoing process." Games in this category are sometimes also called "management games".

The game received strong reviews and was commercially successful, acquiring a cult following among strategy fans; several publications have listed UFO: Enemy Unknown as one of the best video games ever made, including IGN ranking it as the best PC game of all time in 2007. It was the first and best-received entry in the X-COM series and has directly inspired several similar games, including UFO: Alien Invasion , UFO: Extraterrestrials and Xenonauts . An official remake of the game, XCOM: Enemy Unknown , was created by Firaxis Games and published by 2K Games in 2012. Mythos Games' and Julian Gollop's own original spiritual successor project, The Dreamland Chronicles: Freedom Ridge , was cancelled in 2001 and later partially turned into UFO: Aftermath by another developer. Gollop's new X-COM spiritual successor project, Phoenix Point , is currently in development.

Cult following Group of fans who are highly dedicated to a specific area of culture

A cult following comprises a group of fans who are highly dedicated to a work of culture, often referred to as a cult classic. A film, book, musical artist, television series or video game, among other things, is said to have a cult following when it has a small but very passionate fanbase. A common component of cult followings is the emotional attachment the fans have to the object of the cult following, often identifying themselves and other fans as members of a community. Cult followings are also commonly associated with niche markets. Cult media are often associated with underground culture, and are considered too eccentric or subversive to be appreciated by the general public or to be commercially successful.

<i>IGN</i> American entertainment website

IGN is an American video game and entertainment media website operated by IGN Entertainment Inc., a subsidiary of Ziff Davis, itself wholly owned by j2 Global. The company is located in San Francisco's SOMA district and is headed by its former editor-in-chief, Peer Schneider. The IGN website was the brainchild of media entrepreneur Chris Anderson and launched on September 29, 1996. It focuses on games, films, television, comics, technology, and other media. Originally a network of desktop websites, IGN is now also distributed on mobile platforms, console programs on the Xbox and PlayStation, FireTV, Roku, and via YouTube, Twitch, Hulu, and Snapchat.

A PC game, also known as a computer game or personal computer game, is a type of video game played on a personal computer rather than a video game console or arcade machine. Its defining characteristics include: more diverse and user-determined gaming hardware and software; and generally greater capacity in input, processing, video and audio output. The uncoordinated nature of the PC game market, and now its lack of physical media, make precisely assessing its size difficult.


The story of X-COM, set in the near-future at the time of the game's release, begins in the year 1998. The initial plot centers on increased reports of UFO sightings as tales of abductions and rumors of attacks by mysterious aliens become widespread. The nations of the world come to perceive this as a threat and attempt to form their own forces – such as Japan's Kiryu-Kai force – to deal with the crisis, but these efforts are unsuccessful. On December 11, 1998, representatives from some of the most powerful nations in the world secretly meet in Geneva to discuss the issue. From this meeting is born the clandestine defense and research organization Extraterrestrial Combat (X-COM), over which the player assumes control at the start of the game. [3]

Unidentified flying object Unusual apparent anomaly in the sky that is not readily identifiable

Unidentified flying object (UFO) is the popular term for any aerial phenomenon that cannot immediately be identified. Most UFOs are identified on investigation as conventional objects or phenomena. The term is widely used for claimed observations of extraterrestrial spacecraft.

The terms alien abduction or abduction phenomenon describe "subjectively real memories" of being secretly kidnapped by nonhuman figures (aliens) and subjected to physical and psychological experimentation. Most scientists and mental health professionals explain these experiences by factors such as suggestibility, sleep paralysis, deception, and psychopathology. Skeptic Robert Sheaffer sees similarity between the aliens depicted in science fiction films, in particular Invaders From Mars (1953), and some of those reported to have actually abducted people. People claiming to have been abducted are usually called "abductees" or "experiencers".

Geneva Large city in Switzerland

Geneva is the second-most populous city in Switzerland and the most populous city of Romandy, the French-speaking part of Switzerland. Situated where the Rhône exits Lake Geneva, it is the capital of the Republic and Canton of Geneva.

In the beginning, the player will only have access to conventional weapons, but as the game progresses, the player learns more about the enemy, their species, mutated creations, and technology. It is ultimately revealed that the "leaders" behind the alien invasion are a race known as Ethereals which possess powerful mind control abilities and enslave other races of aliens to perform their bidding and that their main base in the Solar System is located in Cydonia region of Mars. The player must then prepare the final assault team, attack Cydonia and destroy the mastermind behind the alien invasion, the biocomputer Alien Brain.

Solar System Planetary system of the Sun

The Solar System is the gravitationally bound planetary system of the Sun and the objects that orbit it, either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, such as the five dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury.

Mars Fourth planet from the Sun in the Solar System

Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war, and is often referred to as the "Red Planet" because the iron oxide prevalent on its surface gives it a reddish appearance that is distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys, deserts, and polar ice caps of Earth.

The game may end in several ways. If the player's performance is poor or worse for two consecutive months, the player runs a deep deficit for two consecutive months, all the player's bases are captured, or the player mounts an assault on the aliens' Mars base and loses, the game ends in defeat in which the council of funding nations makes a futile attempt to negotiate with the aliens. If, however, the player is victorious in the final attack, the game ends in mankind's victory.


The game takes place within two distinct views, called the Geoscape and the Battlescape. [4] According to GameSpy, "Playing it again in 2012, it comes off as both completely brilliant and slightly insane. In effect, X-COM melds an SSI Gold Box RPG with a highly detailed 4X game like Master of Orion , making it in some ways two entirely different games." [5]

GameSpy defunct video game company

GameSpy was a provider of online multiplayer and matchmaking middleware for video games. The company originated from a Quake fan site founded by Mark Surfas in 1996; after the release of a multiplayer server browser for the game, QSpy, Surfas licensed the software under the GameSpy brand to other video game publishers through a newly established company, GameSpy Industries, which also incorporated his Planet Network of video game news and information websites, and GameSpy.com.

Gold Box video game series and game engine

Gold Box is a series of role-playing video games produced by SSI from 1988 to 1992. The company acquired a license to produce games based on the Advanced Dungeons & Dragons role-playing game from TSR, Inc. These games shared a common engine that came to be known as the "Gold Box Engine" after the gold-colored boxes in which most games of the series were sold.

Role-playing game Game in which players assume the roles of characters in a fictional setting

A role-playing game is a game in which players assume the roles of characters in a fictional setting. Players take responsibility for acting out these roles within a narrative, either through literal acting, or through a process of structured decision-making regarding character development. Actions taken within many games succeed or fail according to a formal system of rules and guidelines.


A gameplay screenshot of the continuous-time strategic scale Geoscape mode, with the game's main menu to the right UFO Geoscape.jpg
A gameplay screenshot of the continuous-time strategic scale Geoscape mode, with the game's main menu to the right

The game begins on January 1, 1999, with the player choosing a location for their first base on the Geoscape screen: a global view representation of Earth as seen from space (displaying X-COM bases and aircraft, detected UFOs, alien bases, and sites of alien activity). The player can view the X-COM bases and make changes to them, equip fighter aircraft, order supplies and personnel (soldiers, scientists and engineers), direct research efforts, schedule manufacturing of advanced equipment, sell alien artifacts on black market to raise money, and deploy X-COM aircraft to either patrol designated locations, intercept UFOs, or send X-COM ground troops on missions using transport aircraft. [6] [7]

There are twelve regions of the globe where the player may put bases (North America, South America, Europe, Siberia, North Africa, South Africa, Central Asia, Southeast Asia, Australasia, Arctic, Antarctic, and Pacific) and where alien activity may occur. Aliens have several possible missions they can run, from harmless research missions designed to collect data about the Earth and its inhabitants, to terror attacks on cities with the aim of convincing governments to reduce X-COM's funding.

Funding is provided by the 16 founding nations of X-COM. At the end of each month, a funding report is provided, where nations can choose to increase or decrease their level of funding based on their perceived progress of the X-COM project. [8] Any of these nations may quit if the nation's government has been infiltrated by the invaders. [5] Through reverse engineering of recovered alien artifacts, X-COM is able to develop better technology to combat the alien menace and eventually uncover how to defeat it. [6] [7]


A gameplay screenshot of the turn-based Battlescape tactical combat mode, showing an Alien Terror type mission in urban environment, featuring civilians (click on the image for a more detailed description) Xcom2.png
A gameplay screenshot of the turn-based Battlescape tactical combat mode, showing an Alien Terror type mission in urban environment, featuring civilians (click on the image for a more detailed description)

Gameplay switches to the tactical combat phase whenever X-COM ground forces come in contact with aliens. [4] In the Battlescape screen, the player commands a small group of selected soldiers (at least one) against the aliens in an isometric view and turn-based battle taking place on a semi-randomly generated map. There are nine different terrain types in the game (farmland, desert, forest, ice, mountain, jungle, urban, alien base, XCOM base), each of which pose advantages and disadvantages to the player.

The combat features a system of action points, known in the game as time units, that can be spent for movement and a variety of actions (through an icon-based GUI), including managing equipment, picking up or throwing objects, kneeling down, using items, or priming hand grenades. The time units can be also spent on managing ammunition and discharging firearms, using either a snap shot, an aimed shot, or possibly a burst if a given weapon has an autofire mode (some weapons can also have alternate types of ammunition loaded, such as high-explosive rounds or incendiary rockets). A feature called opportunity fire enables combatants to automatically shoot at a spotted hostile during the enemy turn in case if enough of their time units have been reserved for this. In addition, some aliens possess mind control abilities that can be used to temporarily take control of human soldiers or cause them to panic. By capturing a mind control-capable alien alive, the player will be able to harness these abilities for his squad and eventually use them against the aliens.

One of three mission outcomes is possible: either the human forces are eliminated, the alien forces are neutralized, or the player chooses to withdraw. The mission's score and the result are based on the number of X-COM operatives lost (either dead, unconscious, or under alien control), civilians saved or perished, aliens killed or captured, and the number and quality of alien artifacts obtained. Troops may also increase in rank or abilities if they made successful use of their primary attributes (e.g. killing enemies). [8] Instead of gaining experience points, surviving human combatants might get an automatic rise (a semi-random amount depending on how much of the action in which they participated) to their attributes, such as Psi or Accuracy. The soldiers who have been killed on a mission will remain dead, but can be replaced with raw recruits back at base. In addition to combat personnel, the player may use unmanned ground vehicles that are outfitted with heavy weapons and well armored but large, costly, and not gaining experience. Recovered alien artifacts can then be researched and possibly reproduced. Captured live aliens may produce information, possibly leading to new technologies and even an access to psionic warfare. [6]

One reason for the game's success is the strong sense of atmosphere it evokes. [9] Soldiers are vulnerable to alien attacks even when armored (a single shot from an alien has a good chance of bringing a soldier in perfect condition to death), and the use of features such as night-time combat, a line of sight, and opportunity fire allows for alien sniper attacks and ambushes. [8] The enemy comes in numerous forms, and the players that are new to the game will run into new kinds of aliens without any knowledge of their characteristics and capabilities beforehand. The course of skirmishes is also dictated by the individual morale levels of their participants on both sides; a low morale can result in them either dropping their weapons and fleeing in panic or going berserk and opening fire indiscriminately. [5] At night, the battlefield needs to be illuminated by flares or fires or else the humans can only spot their enemies at a very short range.

Fan-created content

Fan-made patches fix a notorious bug which results in the game always resetting to the easiest difficulty level ("Beginner") after completing the first Battlescape mission, no matter what difficulty level has been selected. This glitch was not noticed by MicroProse and was not fixed in the official patches, resulting in the very high difficulty of the sequel [5] due to many complaints from veteran players who believed that the original game was still too easy even on seemingly higher levels. IBM Master Inventor Scott T. Jones' noted [6] 1995 patch-turned-mod, named XComUtil, [10] fixes it as well as addressing many interface problems and better balancing the game; [6] in 2010, a task of its further development was given to David Jones. [11] OpenXcom is an open-source reimplementation of that game to fix all the known bugs and limits, improve the AI and user interface, localize in more languages, and to provide cross-platform builds, e.g. for Linux and Android. [12] [13] [14] The second focus of OpenXcom is to enable customizing, modding and expansions like the notable total conversion X-Piratez. [15]


The game was originally conceived by a small British video game developer company, Mythos Games – led by Julian Gollop – as a sequel to their 1988 science fiction tactical game Laser Squad , [16] [17] "but with much neater graphics using an isometric style very similar to Populous ." [18] The initial 1991 demo presented a relatively simple, two-player tactical game then known as Laser Squad 2 (or Laser Squad II), which ran on the Atari ST. The Gollop brothers (Julian and Nick) approached three video game publishers, Krisalis, Domark and MicroProse, eventually brokering a deal with MicroProse. [1] [19] Julian Gollop was especially happy about it because he greatly respected MicroProse and believed it was probably the best video game company in the world at the time. [1] [16]

"When we first got the contract with MicroProse we were very pleased but concerned about what they might require us to do. We did have a few arguments in the beginning because they didn’t understand the game design I had written. [...] I had a tough job trying to explain it, and I had to produce a few more documents and attend a big meeting with their in-house designers, producers and head of development."

Julian Gollop [16]

Although supportive of the project, the publisher expressed concerns that the demo lacked a grand scale in keeping with MicroProse's hit strategy game Civilization . The Civilopedia feature of Civilization also inspired an addition of the in-game encyclopedia, called the UFOpaedia. All that and the UFO theme was suggested by MicroProse UK head of development Pete Moreland. [1] [20] Julian Gollop's personal inspirations included several traditional games, in particular, the board wargame Sniper! and the tabletop role-playing game Traveller . [1]

Under MicroProse's direction and working at its Chipping Sodbury studio, [18] Julian Gollop said that while the research and technology tree somewhat emulates the role of advances in Civilization, "it also helped to develop the storyline." [20] He changed the setting to modern-day Earth and expanded the strategy elements, among them the ability to capture and reproduce alien technology. [16] He has cited the 1970s British television series UFO as one of the influences for the game's storyline, in particular, an idea of an international counter-UFO organization and the psionic powers of some alien races, [16] [19] even as the series itself was "a bit boring". [21] A book by Bob Lazar, where he describes his supposed work with recovered UFOs at Area 51, inspired the concept to reverse-engineer captured alien technology. [19] Timothy Good's 1991 book Alien Liaison provided inspiration for several of Julian Gollop's revisions, such as the notion that world governments might seize alien technology or secretly conspire with the invaders (a negative result which can occur in-game). [16] Inspirations also included Whitley Strieber's book Communion and other "weird American stories". [21]

MicroProse UK graphics artists John Reitze and Martin Smillie provided what MicroProse described as "popular 'manga' look and feel" [22] visuals. Julian Gollop credited Reitze with "a distinctive comic book style" and Smillie with "very detailed environment graphics". John Broomhall composed the music while Andrew Parton handled the sound effects. [1] There were also major contributors who were not acknowledged in the game's credits, such as the designer Steve Hand, [23] a Laser Squad fan who helped the project get signed, put input into the "big game" concept, actually came up with the name X-COM (derived from Mike Brunton's initial idea of X-CON, where "CON" originally stood for "contact"), and helped to define the comic book-like art style. [1] Hand thought the original design document was very poorly written, especially regarding the initial, more interactive and action-oriented UFO interception system; nevertheless, the final game turned out to be very close to it. [1] Certain creature types deemed "boring" were removed during the development, as were the Men in Black, who were unused due to a perceived conflict with MicroProse's abortive project to make a MIB-themed standalone game. [23] [1]

A public demo of the game was released under the North American version's working title X-COM: Terran Defense Force. [24] Despite numerous changes from the first demo, the tactical part of the game remains true to the turn-based layout of Laser Squad and the Gollop brothers' earlier Rebelstar series. [16] The AI system of those games formed the basis for enemy tactics, with Julian Gollop programming his own unique algorithms for pathfinding and behavior; in particular, the aliens were purposely given an element of unpredictability in their actions. [1] [16] It was the first game programmed by them for the PC. [19] In retrospect, Julian thought he should have concentrated on game design and left all of the programming work to Nick. Producer Tim Roberts was described by him positively as "very laid back" and for most of the time allowed them to work on the game without any interference and schedules, only checking in once in a month to conduct meetings in a pub. [1]

The original contract was for the game be completed within 18 months. [1] In the course of its development, the game was nearly canceled twice: in the first instance due to the company's financial difficulties, and the second time under the pressure from Spectrum HoloByte after it had acquired Bill Stealey’s shares in MicroProse in 1993. [18] [25] Julian Gollop said the quality assurance team (Andrew Lucket, Phil McDonnel, and Jason Thompson) helped save the game from cancellation; their feedback also helped to polish the game. [1] The game was in fact officially ordered to be canceled by Spectrum HoloByte, but MicroProse UK bosses Pete Moreland, Adrian Parr, and Paul Hibbard held a meeting and decided to ignore it and simply not inform Gollop about any of that. Thus, the development team continued their work without any knowledge of the parent company's executives, [23] [1] until it was eventually completed in March 1994, [16] after 30 months in development since the initial contract. During the final three months, after Spectrum HoloByte was eventually informed of the game still being in production, the Gollop brothers were forced to work 7–12 in order to finish it before the end of the fiscal year. The overall development of the PC version cost £115,000. [1]


The finished product was marketed as UFO: Enemy Unknown in Europe and Australia and as X-COM: UFO Defense in North America. [26] The latter features a different box cover, faithful to the game's contents (the original cover of UFO: Enemy Unknown depicts the aliens and their spacecraft design that are unlike anything actually seen in the game [27] ) and its cartoonish art style. [26] [28] In Japan, the game was renamed by Culture Brain as X-COM Michi Naru Shinryakusha(X-COM 未知なる侵略者,X-COM: Unknown Invaders) [29] and released with a cover using a different art style and better reflecting the actual game content. [26]

Ports and re-releases

The Amiga conversion was done by Julian Gollop's brother Nick and "it was quite tough because the Amiga wasn’t quite as fast as PCs were becoming at that time." [19] The Amiga ECS/OCS version displays lower quality graphics than the PC version and is missing light source shading during combat missions, [21] but the sound quality is improved; the graphics are better in the AGA Amiga version. A Limited Edition for the Amiga CD32 came with a MicroProse travel alarm clock. [26]

The original PC release from 1994 was distributed on floppy disks and requires the player to enter copy protection codes from a provided booklet. A year later, a CD version was released that removed the copy protection and made a few changes such as different alien death noises.

The 1995 PlayStation port has retained the original graphics due to time restraints (adding only some 3D models as illustrations for the UFOpaedia) but features much higher quality music than the PC version (55 minutes of CD-quality tracks and 8 minutes of 16-bit tracks instead of the 8-bit MIDI music). [30] The new music was composed by Allister Brimble, who later also created the music for the first sequel, X-COM: Terror from the Deep . It is compatible with the highly recommended [31] [32] [33] PlayStation Mouse and requires five PlayStation memory card blocks for a Battlescape saved game. [31]

The game was re-released as part of the compilations X-COM: Unknown Terror by MicroProse and Prima Games in 1996, [34] X-COM (Collector's Edition) by MicroProse in 1998, [35] X-COM Collection by Hasbro Interactive in 1999, [36] X-COM: Complete Pack by 2K Games in 2008 and 2K Huge Games Pack in 2009, [37] as well as in the "Classic Games Collection" CD featured with the July 2000 issue of PC Gamer . In X-COM: Complete Pack (also known as X-COM Collection [38] ), all five X-COM games were released for paid download on Steam with added Windows XP and Windows Vista support. [39] There were also several Amiga and PlayStation re-releases.


Diane Duane's 1995 X-COM: UFO Defense – A Novel ( ISBN   0-7615-0235-1) tells the story of Jonelle Barrett, commander of X-COM's newly established Swiss base. [40] According to Rock, Paper, Shotgun's negative review of Duane's novel, it is hampered by a poor understanding of the game, a lack of focus, emotional resonance and tension, and an unstructured plot. [41]

Another novelization of the game, Враг неизвестен ("Enemy Unknown") written by Vladimir Vasilyev, was published in Russia in 1997. The book tells the story of one of the original eight X-COM troops from beginning of the conflict to the final raid on Cydonia. [42]


Aggregate score
GameRankings PC: 94% [43]
PS: 93% [44]
Review scores
CGW PC: Star full.svgStar full.svgStar full.svgStar full.svgStar full.svg [45]
EGM PS: 8.8/10 (9.5/9.5/8.5/8.0) [46]
Game Informer PS: 8.5/10 [31]
GameSpot PC: 9.0/10 [7]
IGN PC: 9.4/10 [6]
PS: 9.0/10 [32]
Next Generation PS: Star full.svgStar full.svgStar full.svgStar full.svgStar full.svg [33]
Amiga Action 9.2/10 [47]
Amiga Format 9.0/10, 9.0/10 [48] [49]
Amiga Power 3.6/10 and 6.6/10 [50]
AGA: 7.5/10 and 8.5/10 [51]
CU Amiga 8.5/10, 9.3/10 [52] [53]
AGA: 8.9/10 [54]
The One 7.3/10 [55]
AGA: 8.9/10 [56]
CD32: 8.6/10 [57]

The game was released to very positive reviews and commercial success, selling more than 600,000 units on the PC DOS platform, not counting the later ports—for the Amiga platforms and the PlayStation—and re-releases. Half of the game's net sales were in the United States, a rarity for a European title at the time. Gollop has attributed the game's North American success to its title (X-COM), as the television series The X-Files had premiered a year earlier. [16] More than 400,000 units were sold at full price, with little marketing from its publisher. [58] Together with its sequel, X-COM: Terror from the Deep , its sales had passed 1 million copies by March 1997. [59] The game earned the Gollop brothers just over £1 million in royalties. [1] The game became very popular also in Russia, even as there were no royalties from that market as it was only distributed there via software piracy. [19]

Computer Gaming World rated X-Com five stars out of five. Describing it as "one of those rare and dangerous games capable of drilling into your brain, putting a vice-grip on your imagination, and only releasing you when it has had enough", the magazine praised its detailed and varied combat system and lengthy gameplay, concluding "Resistance is futile". [45] A preview of the PlayStation version in Next Generation called it "one of the best PC strategy games ever". [30] GameSpot said, "put simply, X-COM is a bona fide modern classic, standing proudly alongside Civilization and Populous as a benchmark in the evolution of strategy gaming". [7] Electronic Gaming Monthly stated of the PlayStation version that "any person who likes strategy games will fall in love with this title ... if you could afford to buy one game for the PS over the next year, X-COM would be it. It has it all and then some!" [46] A reviewer for Next Generation criticized the PlayStation version for being little more than a straight port, arguing that the game could have been improved if the console's capabilities were used. However, he praised the game itself for sophisticated, enjoyable gameplay, and concluded, "X-Com was a smashing PC title, it's lost nothing of practical value in the translation, and makes a marvelous addition to the console market". [33] GamePro disagreed: "You have to be a major sim-freak to enjoy X-Com. It's an interesting and complex game about planet colonizing, but the extensive manuals and one-dimensional music really bore you to alien tears after a while". [60]

Amiga ports received lower ratings than the PC original (which holds an average score of 93.60% at GameRankings [43] ), according to Amiga HOL database having averaged scores of 79% on the ECS/OCS Amigas, 82% on the AGA Amigas and 73% for the Amiga CD32 version. [61] [62] [63] A common point of criticism for the floppy disk version was the need to frequently swap the disks in the Amiga systems not equipped with a hard disk drive, while the CD-ROM based CD32 version does not allow the users to save the progress of any other game without wiping out the save game of UFO. Nevertheless, a review in Amiga Action called it "easily the most original and innovative game in the history of the Amiga", [47] a review in Amiga World called in "the shortest path to heaven" for a strategy gamer, [64] and a review in CU Amiga of the 1997 budget range re-release called it the "game everyone loves". [53]

Computer Gaming World gave X-Com its Game of the Year award. [65] PC Gamer US presented Enemy Unknown with its 1994 "Best Strategy Game" award. The editors wrote, "X-COM's classic mix of action and strategy will have you hooked for hours, and made this one of the finest games of the year." [66]


In 2009, Edge called X-Com "the title that first brought turn-based wargaming to the masses." [16] It has often appeared in top video game lists by various publications. Computer Gaming World ranked it as the 22nd (1996) [67] and third (2001) best computer game of all time; the magazine's readers also voted it for tenth place in 2001. [68] It was ranked as the 26th top game of all time by Next Generation in 1996 ("breathed new live into turn-based strategy genre"), [69] the 35th best video game of all time by GameSpy in 2001 ("stellar game design can withstand the test of time"), [70] as the second best video game since 1992 by Finnish magazine Pelit in 2007, [71] and as the 78th best video game "to play today" by Edge in 2009. [72] Polish web portal Wirtualna Polska ranked it as the 13th best Amiga game, [73] as well as the third most addictive game "that stole our childhood"; [74] it was also retrospectively ranked as the eighth best Amiga game by the Polish edition of CHIP . [75] In 2015, Rock, Paper, Shotgun listed it as their 6th "Best Strategy Games Ever Made" ("in the thick of a terror mission, with chrysalids seeming to pour out of the walls, or in those last hours when you finally seem capable of taking the fight to the aliens, there’s nothing else quite like X-COM") [76]

IGN named it as the number one top PC game of all time in 2000 ("the finest PC game we have ever played") and 2007 ("there's still no PC game that can compete with the mighty X-COM"), [77] [78] as well as ranking it as the second top "modern PC game" in 2009. [79] IGN also included it on several lists of the best video games of all time on all platforms, including it at eighth place in 2003 ("a game that will live on in the annals of computer gaming history"), [80] at 12th place in 2005 ("for us 1994 will always be remembered as the year of X-COM"), [81] and at 21st place in 2007 ("one of the most memorable and perfectly executed strategy games ever seen"). [82] PC Gamer ranked it as the seventh (1997), [83] eighth (1998), [84] third (2001), [85] eighth (2005), [86] tenth (in both 2007 and 2008, as a "truly groundbreaking game" that "still plays fresher than almost anything else that begs passage through these pages"), [87] [88] 11th (2010, the editors adding that everyone who would not vote for this game is "dead" to them) [89] and 12th (2011, describing it as a "brilliant game whose individual elements have been copied many times but whose charm has never been duplicated") best PC game of all time; [90] it was also voted at 15th place by the magazine's readers in 2000. [91]

It was also inducted into several halls of fame, including by CGW in 2005 ("a great game which proves that pushing the technological envelope is often less important than stoking the gamer's competitive fire"), [92] by GameSpot in 2003 (featured among The Greatest Games of All Time as "one of the defining games of the turn-based strategy genre"), [93] and by IGN in 2007 ("if this game were a woman, we'd marry it"). [94] In 1996, CGW ranked it as the number one sleeper hit of all time. [95] In 1999, the game's Xenomorph-inspired [21] alien race of Chryssalids was ranked as fourth on the list of best monsters in gaming by GameSpot, where X-COM was also called "one of the scariest computer games ever". [96] In 2012, while awaiting the remake, The Escapist ran a feature article about "why X-COM is the greatest game ever" [8] and game designer Ken Levine named it as one of his all-time personal favorites. [97] That same year, 1UP.com ranked it as the 90th most essential game of all time, commenting that "with its unrivaled balance of tactics and tension, XCOM remains a masterpiece." [98] [99]


The success of the game resulted in several sequels and spin-off games, as well as many unofficial remake and spiritual successor titles, both fan-made and commercial. Julian Gollop himself designed the third game in the X-COM series, 1997's X-COM: Apocalypse , which was also developed together by Mythos Games and MicroProse. The game also received an unofficial sequel in the 1997 expansion set Civ II: Fantastic Worlds for MicroProse's Civilization II , in a scenario set on the Phobos moon of Mars. [100] During the late 1990s, MicroProse was developing a quasi-reboot game, X-COM: Genesis , but this was canceled.

The Gollop brothers' ambitious attempt to create their own independent, 3D quasi-remake, The Dreamland Chronicles: Freedom Ridge , was cancelled in 2001 due to financial problems and a failure to find a publisher, resulting in the bankruptcy of Mythos Games (resources from the unfinished game were then bought by a Czech company Altar Games and turned into UFO: Aftermath , which was itself followed by two sequels, UFO: Aftershock and UFO: Afterlight ). Julian Gollop's new company, Codo Technologies, released two low-budget tactical games with the gameplay reminiscent of the Battlescape mode of Enemy Unknown, Laser Squad Nemesis (2002, retitled in Poland as UFO: Gniew Boga [101] ) and Rebelstar: Tactical Command (2005), both of them also sharing with X-COM the theme of a human-alien war. His new X-COM spiritual sequel project, Phoenix Point , is currently in development by Snapshot Games for a planned 2019 release.

An official remake, titled XCOM: Enemy Unknown , was developed by Firaxis Games, led by MicroProse's co-founder Sid Meier. The game's prototype was actually a modernization of the original, with all the classic gameplay features, [7] [102] but then gradually evolved into a completely "reimagined" version. The game was released by 2K Games for Microsoft Windows, PlayStation 3 and Xbox 360 in October 2012, winning multiple Game of the Year awards. In a retrospective article in Eurogamer, Alec Meer compared both games with "a sort of objectivity from me that hasn't been remotely possible over the last two decades of worshipping at its VGA shrine," stating: "I can see a game that can and will co-exist with rather than be supplanted by its remake. X-COM and XCOM are completely different games, both ingenious and both flawed in their own ways. I'd kill for a hybrid of the two, but having two rather than one sure is nothing to sniff at." [103] In a positive review of the remake, Dan Stapleton of GameSpy added: "I leave the title of Best Game Ever with the original." [104] Julian Gollop himself commented that "Firaxis did a terrific job with the new XCOM," although he "would have done things differently for sure. (...) I tried many times for many years to get a remake underway, but Firaxis finally did it. Also, there is a promising and more faithful remake called Xenonauts ." [105]

The game also had a big influence on the development team of the role-playing video game Fallout . Project director Tim Cain said they "all loved X-COM" and that the original version of Fallout (known as Vault 13, before the game was redesigned after they lost the GURPS license) had a very similar combat system. [106]

Related Research Articles

Strategy game type of game in which the players decision-making skills have high significance in the outcome

A strategy game or strategic game is a game in which the players' uncoerced, and often autonomous decision-making skills have a high significance in determining the outcome. Almost all strategy games require internal decision tree style thinking, and typically very high situational awareness.

<i>X-COM</i> Video game series

X-COM is a science fiction video game franchise featuring an elite international organization tasked with countering alien invasions of Earth. The series began with the strategy video game UFO: Enemy Unknown created by Julian Gollop's Mythos Games and MicroProse in 1994. The original lineup by MicroProse included six published and at least two canceled games, as well as two novels. The X-COM series, in particular its original entry, achieved a sizable cult following and has influenced many other video games; including the creation of a number of clones, spiritual successors, and unofficial remakes.

<i>X-COM: Apocalypse</i> 1997 video game

X-COM: Apocalypse is the third game in the X-COM video game series. It was developed by Mythos Games, and published by MicroProse in 1997 for MS-DOS and Microsoft Windows.

<i>X-COM: Terror from the Deep</i> video game

X-COM: Terror from the Deep is a strategy video game developed and published by MicroProse for the PC in 1995 and for the PlayStation in 1996. It is a sequel to UFO: Enemy Unknown and the second game of the X-COM series, this time taking the war against a renewed alien invasion into the Earth's oceans.

<i>Master of Magic</i> 1995 video game

Master of Magic is a single-player, fantasy turn-based strategy 4X developed by Simtex and published by MicroProse for MS-DOS in 1994. The player plays as a wizard attempting to dominate two linked worlds. From a small settlement, the player manages resources, builds cities and armies, and researches spells, growing an empire and fighting the other wizards.

<i>X-COM: Alliance</i> computer game

X-COM: Alliance is a cancelled video game in the X-COM series. The game was developed by three different teams of MicroProse developers between 1995 and 2002. The game had the player assume the role of commander of the militarized scientific mission lost in space during the aftermath of X-COM: Terror from the Deep.

<i>Rebelstar: Tactical Command</i> 2005 video game

Rebelstar: Tactical Command is a turn-based tactics video game developed by Codo Technologies and published by Namco for the Game Boy Advance in 2005. The game was created by Julian Gollop, who has previously designed UFO: Enemy Unknown games and the original Rebelstar games.

<i>The Bureau: XCOM Declassified</i> 2013 science fiction video game

The Bureau: XCOM Declassified is a tactical shooter video game played in third person. It was developed by 2K Marin and published by 2K Games. As the eighth title in the turn-based strategy series X-COM and a narrative prequel to XCOM: Enemy Unknown, the game was released for Microsoft Windows, PlayStation 3 and Xbox 360 in August 2013. Set in late 1962 at the height of the Cold War, the game's premise mainly revolves around The Bureau, the predecessor of the Extraterrestrial Combat Unit (XCOM), as they attempt to repel an alien invasion. As a tactical shooter, players can use the battle focus mode to issue commands to two other agents accompanying the protagonist, William Carter. Players can permanently lose their squad members so they must make good tactical decisions.

UFO: Alien Invasion is a strategy video game in which the player fights aliens that are trying to take control of the Earth. The game is heavily influenced by the X-COM series.

<i>The Dreamland Chronicles: Freedom Ridge</i>

The Dreamland Chronicles: Freedom Ridge is an unreleased video game for Microsoft Windows and PlayStation 2 by Mythos Games. Developed by the team which produced UFO: Enemy Unknown, including lead designer Julian Gollop, the game was planned to be "a remake of the first X-COM with 3D graphics," as the first of four games planned in the new series.

<i>XCOM: Enemy Unknown</i> video game

XCOM: Enemy Unknown is a 2012 turn-based tactical video game developed by Firaxis Games and published by 2K Games. The game is a "reimagined" remake of the 1994 cult classic strategy game UFO: Enemy Unknown and a reboot of MicroProse's 1990s X-COM series.

<i>XCOM: Enemy Within</i> 2013 video game

XCOM: Enemy Within is an expansion pack for the turn-based tactical video game XCOM: Enemy Unknown. The expansion pack primarily adds new gameplay elements to the base game, as well as introducing new themes of transhumanism via aggressive gene therapy.

<i>XCOM 2</i> turn-based tactical video game developed by Firaxis Games

XCOM 2 is a turn-based tactics video game developed by Firaxis Games and published by 2K Games for Microsoft Windows, OS X, and Linux in February 2016, and for PlayStation 4 and Xbox One in September 2016. The game is the sequel to 2012's reboot of the series, XCOM: Enemy Unknown. Taking place 20 years after the events of Enemy Unknown, it follows the continuity that XCOM, a military organization trying to fight off an alien invasion, has lost the war, and is now a resistance force against their occupation of Earth and their established totalitarian regime and military dictatorship. The expansion XCOM 2: War of the Chosen was released in 2017.

Long War is a fan-made partial conversion mod for the turn-based tactics video game XCOM: Enemy Unknown and its expansion, XCOM: Enemy Within. It was first released in early 2013, and it exited beta at the end of 2015. Almost every aspect of the original game is altered, creating a longer, more complex campaign that presents players with more strategic choices and customization options. Long War adds a significant number of new soldier classes, abilities, weapons, armors, and usable items, and also introduces new features, including soldier fatigue and improvements to alien units over the course of the game.

<i>XCOM 2: War of the Chosen</i>

XCOM 2: War of the Chosen is an expansion pack for the 2016 turn-based tactics video game XCOM 2. It was released for Windows on August 29, 2017. Versions for macOS and Linux were released on August 31, 2017.

<i>Phoenix Point</i> upcoming strategy video game

Phoenix Point is an upcoming strategy video game featuring a turn-based tactics system that is being developed by Bulgaria-based independent developer Snapshot Games for release on September 3, 2019 for the Xbox One, macOS and Microsoft Windows via Epic Games Store. Phoenix Point is intended to be a spiritual successor to the X-COM series that had been originally created by Snapshot Games head Julian Gollop during the 1990s.


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