Chinpokomon - S3-E11
Audio problem: Near the end of the episode, where the boys are standing at the bus stop and Kenny (who is in a seizure trance) starts getting attacked by rats, Cartman yells, "Hey, get away. He's not dead yet", but it doesn't sound like Cartman (the tone seems more high-pitched.).
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.
Bishop73