Game Information

Original Release Date: November 10, 1999

Platforms: Linux, Mac, PC (Microsoft Windows)

Involved Companies: Gearbox Software, Sierra Entertainment, Valve

Genres: Shooter, Platform, Puzzle

Summary: Opposing Force returns to the same setting as Half-Life, but instead portrays the events from the perspective of a U.S. Marine, one of the enemy characters in the original game. The player character, Adrian Shephard, is sent in to neutralize the Black Mesa Research Facility after a scientific mishap causes it to be invaded by aliens, but quickly finds that the Marines are outnumbered and slowly being beaten back by a second alien race and black operations units.