X-Men: The Ravages Of Apocalypse, developed by Zero Gravity Entertainment and released by WizardWorks Software, is a commercial total conversion of the Quake engine released in 1997. Replacing the original Quake levels and weapons are new designs, and all of the enemies in the game have been replaced with cyborgclones of popular X-Men characters, all with their own special powers—for example Archangel is immune to rockets, Wolverine has his healing factor, etc. X-Men: The Ravages of Apocalypse was one of the first total conversions to feature a high profile property.
Being a total conversion rather than a completely new game, it required the full version of Quake to be played.
X-Men: The Ravages of Apocalypse was released as freeware in July 2006. The game's source code was also released, but under an ambiguous license. Modifications have been made to the game to allow it to run as a standalone title.