Operation: Kill BJ is a mod for registered Wolfenstein, made by Tricob. It was released on August 19, 2001.
The mod features 60 new levels and a large number of changed wall textures. The original release did not contain any changes to the source code.
In December 2012, an SDL port of the mod was released, which featured source code changes in addition to a handful of levels being remade. Adam Biser helped out with the graphics, among which a very effective READY sign greets the player upon beginning.