* PigeonholedVoiceActor: John St. John reprises once more his role as The Duke himself.
* WhatCouldHaveBeen: Dr. Proton, from the first game, was going to be brought back as the final boss of the game, but was scrapped in favor of Morphix, since his presence would have affected the intended VideoGame/DukeNukemForever storyline at the time.