Based on 1994 Mythos/MicroProse PC (DOS) release. PC versions: VGA
NB.  Initially began life on the Atari ST as LASER SQUAD 2, but the final product never saw the light of day on the machine.
 Released as X-COM: ENEMY UNKNOWN on PSX in Europe
Page views: 4597 - Last update: 2nd November 2013
One version is common, at least one other version is rare
 Game design by Julian & Nick Gollop. CD32 conversion by Bob Koon and Scott Johnston; additional coding by Adrian Scotney, Tim Cannell, Nick Thompson and Paul Dunning.
 X-COM: UFO DEFENSE, the U.S. release, reportedly has fixed bugs that prevented completion of the European release.
TRIVIA: The game initially began life as LASER SQUAD 2 on the Atari ST. Game designer Julian Gollop shared these revealing insights on the early beginnings and subsequent development of Mythos Games' best-selling title:
'We showed a demo of ‘Laser Squad 2’ on the Atari ST to MicroProse in 1991. The idea was to produce a sequel to ‘Laser Squad’ but with much neater graphics using an isometric style very similar to Populous. They liked what we had done so far, but they explained that they wanted a ‘big’ game. I said "what do you mean by ‘big’" and they said "well, you know – BIG". They also said that it had to be set on earth, like Civilisation or Railroad Tycoon, because people could relate to it much more. So we went away, scratched our heads and thought about it. Then we came up with the idea of adding on a grand strategic element to the game, very firmly set on earth, in which the player managed an organisation that defended the planet against UFO incursions. I bought quite a few books on UFOs for research purposes so that we could give the game an even more ‘authentic’ basis.
The project started reasonably well with myself and Nick designing and programming, while the art was to be done by John Reitze and Martin Smillie at MicroProse. Soon we had some problems because MicroProse did not understand our game design and they asked for clarification. Several documents later we were not much better off and I had wasted a lot of time. Certain creature types were removed, including the ‘Men In Black’ and others added. Then the whole project was nearly axed when MicroProse made some cutbacks due to financial difficulties. Everything proceeded reasonably smoothly for a while until Spectrum HoloByte acquired Bill Stealey’s shares in the company. Our producer was made redundant and the game was nearly axed again. Finally we had to spend a couple of months working very long hours at MicroProse in Chipping Sodbury to get the game finished by the end of March in 1994' [Source: Mythos Games (old website), courtesy of the Internet Archive].