According to creators Zach Hadel and Michael Cusack, the blonde woman seen with Glep in the Halloween and Christmas episodes is Glep's wife and is named Marge Simpson, but the character has never seen The Simpsons (1989) and gets annoyed when people bring it up to her.
The episode 'Frowning Friends' had a very troubled production and was the last to be finished, which resulted in several humorous oddities such as Mr. Man's head shifting into D.J. Spit's head at the end of his scene as the creators couldn't figure out how to end the scene and the Renaissance Men were a very late addition as a way to kill off Grim and Gnarly. Also, D.J. Spit was originally going to have visible pubic hair due to his low pants, but this was erased by the censors in the broadcast version. Zach Hadel said that if he had the time to figure out who had censored the hair, he would have credited them as 'digital pube remover' in the episode's credits.
They originally intended to use the Comic Sans font for the credits but were unable to acquire the rights to use it.
Originally Pim was going to die and go to hell in the season finale, but the creators decided it would make more sense for Charlie to undergo such a journey, given his more lazy and apathetic personality.
Michael Cusack and Zach Hadel originally wanted Dan Aykroyd to play the host in 'A Silly Halloween Special' as an affectionate joke about Aykroyd's fascination with and belief in the paranormal. When Aykroyd proved unavailable, Jim Knobeloch was hired instead.