Planet J: Captain Buck Tanner and the Space Clowns from Hades was a Wolfenstein 3D project by Jayngo and Nexion, with additional graphics from Atina.
The mod was in the works circa 2009-2010, and was based on Planet Nexion, however with a more colorful palette and a few goofs, such as Michael Jackson sounds. Work on the project did not progress further for a long time, as Jayngo got busy in his private life.
No screenshots or artwork has surfaced of the mod.