Dungeon Cephalis is a mod for registered Wolfenstein, made by Amirtes. It was released on May 16, 2001.
It carries a macabre and slightly satanic theme, and some sprites and sounds were borrowed from DOOM. The mixture of the macabre and the absurd made for quite an enticing gameplay, and for a time it was unofficially deemed one of the weirdest mods ever made.
8 new levels are featured on Episode 1 (E1L5 and E1L10 remains unchanged). A revised version was released on June 25, 2003 (deemed v0.51) featuring a handful of changed graphics.
The original 2001 version was never submitted to the Dome, and could instead be found on Dave's Wolf 3-D Shrine (now defunct).