Factual error: Kyle says he has to log on before school. The next shot shows "Monday 8 days later." 8 days before is a Sunday. (00:04:45)
Cartman Gets an Anal Probe - S1-E2
Continuity mistake: In the classroom there is a poster of The Laughing Cavalier in the back wall in the class. In the last shot of that scene you can notice that the poster has disappeared and is replaced with an astronaut poster. (00:09:05)
Woodland Critter Christmas - S8-E14
Continuity mistake: The narrator says that it's "Christmas Eve day," but then the abortion doctor says that it's "three days until Christmas."
Continuity mistake: Butters' dad's first name changes from Chris to Steve as the series progresses.
Scott Tenorman Must Die - S5-E4
Plot hole: When Scott Tenorman shows the other kids a video of Cartman doing his "piggy" act, the angle of the video shot shows that it could only have been taken from the place where Scott was standing when Cartman originally did it - but Scott is seen at that time to have no video camera or any way to have recorded this.
Cartmanland - S5-E6
Plot hole: How was Cartman able to afford a fairly lengthy TV ad, when he had already spent all his money on the theme park? Cartman took all his money with him to buy the theme park. After buying the park, he runs the TV ad mocking Stan and Kyle. Soon after, when he hires the security guard, he reiterates that he had spent all his money to purchase the theme park. Cartman would not be able to get a loan (he is too young), even as a co-signer. Cartman's mother is also not wealthy enough to give him the money.
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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