Quake II is an FPS developed by Id Software and published by Activision in 1997.
Mankind is at war against the Strogg, a hostile alien cybernetic race. You are Bitterman, a marine taking part in the invasion of their home world.
The game was not supposed to be a sequel to Quake, but when the team could not decide on a title, they went back to the old, recognizable one. Although the gameplay was similar, the setting and aesthetics were vastly different. Its industrial metal soundtrack was composed by German musician Sascha Dikiciyan, aka Sonic Mayhem.
Quake II was far more advanced than its predecessor, featuring 3D acceleration out of the box.
Bitterman is playable in Quake III Arena, but his bio tells that he was captured by the Strogg and turned into a cyborg. As the game is built around multiplayer, it does not have much of a plot. Quake 4, developed by Raven Software and released in 2005, continued the Quake II plot; it reused that concept, but with a different protagonist being turned into a cyborg.