Chokage is a mod for registered Wolfenstein, made by Chris Chokan. It was released on August 27, 1998.
The first mod to alter the Wolfenstein source code, the mod features a bizarre universe created by Chokan, featuring off-beat humor and surrealistic sprites and actors. Many new graphics and sounds are featured, though the original Wolfenstein feel is definitely not lost.
The mod featured a brand new EXE which also allowed for playback of several other mods. One function, Krazzy Chokage, featured a different keyboard setup which made playback quite difficult and bizarre.
Though overtly silly in nature, the mod still featured some clever map design, and the very fact that the source code had been altered significantly is also noteworthy.
Earlier versions did exist and were for a while available on Herc's Super Chokage page, including Chokage 96 and Chokage v1.0. Chokage v1.0 features only the map files and a new VSWAP, and is thus playable in SDL.
The mod is still only available in DOS. Efforts to get Chokan to re-release the mod in SDL have proved futile, with the first of many attempts being by Andy Nonymous and Thomas Weiling in 2013 to coincide with the mod's 15th anniversary.