Wolfenstein 3D Second Edition is a mod for registered Wolfenstein. It was made by Spenser Whaley, and was originally released on his own site in July 2003. Six years later, it was posted on the Dome.
It features 11 levels (10 new levels on episode 1 and 1 new level on Episode 2) of generally good quality and numerous graphical and source code changes.
Sadly, a bug that affects saved games was never fixed.