UFO: Enemy Unknown - Development

Development

The game was originally conceived by a small British video game developer company Mythos Games - led by Julian Gollop - as a sequel to its 1988 science fiction tactical game Laser Squad, "but with much neater graphics using an isometric style very similar to Populous." 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 several video game publishers, including Krisalis and Domark, eventually brokering a deal with MicroProse, producer of Sid Meier's Civilization.

Although supportive of the project, the publisher expressed concerns that the demo lacked a grand scale in keeping with its just-released hit strategy game Civilization. Julian Gollop said, "In fact the research and technology tree somewhat emulates the role of advances in Civilization, but it also helped to develop the storyline." The Civilopedia feature of Civilization also inspired an addition of the in-game encyclopedia, called UFOpaedia. The UFO theme was suggested by MicroProse head of development Pete Moreland. Under MicroProse's direction and working at its Chipping Sodbury studio, Julian Gollop changed the setting to modern-day Earth and expanded the strategy elements, among them the ability to capture and reproduce alien technology.

Julian Gollop 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 organisation and the psionic powers of some alien races, even as the series itself was "a bit boring." 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. Timothy Good's 1991 book Alien Liaison provided inspiration for several of Julian Gollop's revisions, including the notion that world governments might seize alien technology or secretly conspire with the invaders (a negative result which can occur in-game). Inspirations also included Whitley Strieber's book Communion and other "weird American stories". Certain creature types were removed during the development, including the Men in Black. The original name for X-COM was "Xcomm".

MicroProse graphics artists John Reitze and Martin Smillie provided "popular 'manga' look and feel" visuals; John Broomhall composed the music. A public demo of the game was released under the North American version's working title X-COM: Terran Defense Force. Despite numerous changes from the first demo, the tactical part of the game remains true to the turn-based layout of Laser Squad and Julian Gollop's earlier Rebelstar series. The artificial intelligence 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, giving the illusion of a lifelike, resourceful enemy. 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.