Developed with the id Tech 3 engine (Quake 3, Call of Duty), RTCW was a looker of a game for its time, and even to this day, it has enough dark fantasy elements to make it stand out among its peers. Return to Castle Wolfenstein answered that question in more ways than probably intended. Beyond Doom being a huge success, Wolfenstein's concept and execution of said concept were pretty straight to the point: You're a dude killing Nazis. Gray Matter Interactive’s take on Wolfenstein returned to a world that had been untouched since id Software wrapped up production on 3D’s post-release episode, Spear of Destiny.