Dr. Doomsday

Dr. Doomsday is the archenemy of Radioactive Squid Woman, both made up by Buster.

He is intelligent enough to build a hover-scooter, so he seems a powerful adversary. He also had some sort of "pickle factory accident" because of Squid Woman, and vows revenge for it. It is unknown if he lost his head from the accident, or if the pickle was "lodged" in his already jar-shaped head.

Arthur

 * "Jenna's Bedtime Blues"

Trivia

 * He is a parody of Mysterio from Spider-Man, but his name is a combination of Doctor Doom and Doomsday, from Fantastic Four and Superman, respectively.