System Shock 2 is hard to categorize, because it blends several genres and styles of games so well. It's a Role-Playing First-Person Shooter Science Fiction Survival/Horror game, with some extra twists here and there. If you wished Half-Life was more like Deus Ex, or you wanted to play the more violent and scary parts of Thief with 22nd century firepower, this is the game you want to play.