Mr. Hankey, the Christmas Poo - S1-E10
Character mistake: When the class are practising the nativity, Mrs Broflovski comes in and berates Mr Garrison for casting Kyle in the part of Joseph of Arimathea, but Joseph of Arimathea wasn't the husband of Mary, Jesus' mother, but a disciple of Jesus who helped in the burial of Jesus after his crucifixion.
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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