Aliens versus Predator

Aliens versus Predator is a science fiction first-person shooter computer game developed by Rebellion Developments and published by Sierra. It was officially released for Windows and Mac in 1999, followed by an unofficial port to Linux in 2001, following Rebellion's public release of the game's source code. A sequel, Aliens versus Predator 2, was developed by Monolith Productions, and released by Sierra in 2001.

The storylines of the three player characters are independent of one another. As an Alien, the player must defend the Alien hive from human Marines, then defeat Predators on the way to Earth. When playing as the Colonial Marine, the player begins at a research station on LV-426, which was built to study the derelict spacecraft where the Nostromo crew first encountered the Alien eggs in the film Alien. The player battles Aliens and Predators there, on another space station, and finally on a spaceship. The Predator character's storyline visits three different planets, fighting Aliens and Marines on the first two, and taking on the Alien nest on the last planet.