Trivia: The creators of the show, Matt Stone and Trey Parker, based the Stan Marsh and Kyle Brosfloski characters after themselves (Stan being Parker and Kyle being Stone.) The Eric Cartman character was partly based on Archie Bunker.
Trivia: Dr. Mephisto is based on Marlon Brando in The Island of Dr. Moreau (1996).
Trivia: Liane was the name of Trey Parker's ex-fiance who left him a month before their wedding, which explains a lot of the jokes about Cartman's mom.
Trivia: Mr. Mackey was based on a school counselor Trey Parker had in Jr. High school (confirmed by Trey).
Trivia: Trey Parker and Matt Stone are big Star Trek fans and try to slip at least one Star Trek reference into each episode.
Trivia: While an episode of The Simpsons takes several months to complete, an episode of South Park of the same length take only about a week to complete.
Trivia: Nancy Cartwright, the voice of Bart Simpson, was given the opportunity to do voicework on the show, but turned it down due to its offensive content.
Answer: He appears in at least 5 other episodes, but usually just as a background character. He can be seen at Cartman's party in "Immaginationland". He was also one of the kids trying out to replace Butters in the "Professor Chaos" episode.
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