Read more about X-COM Extra Terrestrial Combat Unit at: Wikipedia

Official Site: Take Two Interactive

X-COM (or X-Com/XCom ) is a science fiction video game franchise that began with a classic strategy game UFO: Enemy Unknown by Mythos Games and MicroProse in 1993 and ultimately spanned six finished and two cancelled games, as well as two novels, until 2002. An X-COM reboot series, entitled XCOM, was announced by 2K Games in 2010. It also directly inspired several other video games.

The X-COM core series consisted of four main games published by MicroProse: UFO: Enemy Unknown (also known as X-COM: UFO Defense and originally released in 1993-1994 for the PC, with later ports for the Amiga and Sony PlayStation), X-COM: Terror from the Deep (PC in 1995 and the PlayStation in 1996), X-COM: Apocalypse (PC, 1997) and X-COM: Interceptor (PC, 1998).

The premise of the franchise is that a mysterious alien invasion has began in 1999 (a near future at the time of the first game's release). In response, a coalition of funding nations create an elite clandestine paramilitary organization codenamed X-COM (an abbreviation of "Extraterrestrial Combat Unit") as mankind's last hope. The player is charged with leading this secret force, tasked with a mission to engage and research the alien threat. At the end of the successful game, the X-COM manages to capture and reverse engineer enough of the invaders' technology to decisively turn it against them. The sequels took the fight against new alien invasions underwater (Terror from the Deep, set in 2040), into a futuristic megacity (Apocalypse, set in 2074), and eventually into space (Interceptor, set in 2067, which actually makes it a prequel to Apocalypse).

Enemy Unknown, featuring a turn-based ground combat system, remains by far the most popular and successful game in the series and has been often featured on the various lists of best video games of all time. The first sequel, Terror from the Deep, was quickly created by MicroProse's internal team and based on the same game engine and used largely identical gameplay mechanics. Apocalypse took several new directions with the series, introducing an optional real-time combat system and shifting the aesthetics to a retro-futuristic style. However, despite being developed by Julian Gollop's British studio Mythos Games, the original creators of Enemy Unknown, it failed to repeat its smash success. The last released X-COM main game, Interceptor, constitutes a hybrid of a strategy game and a space combat flight simulator.

X-COM Extra Terrestrial Combat Unit has not been a contender in any CBUB matches.