Personally I’ve watched the series every now and then, but not enough to know every single episode.
So frankly I was curious on what people thought was the most diabolical joke/ skit they’ve ever done. considering this series has tons of them, I’ll probably get a good chuckle from the best ones
The two episodes that have always stood out to me as the most F’d up are World Wide Recorder Concert (Mr. Harrison being upset that his dad never molested him) and Cartman Joins NAMBLA.
As far as individual jokes, I find Detective Harris blasting semen out of his butt into an evidence bag to be pretty disturbing. Same with the idea of everyone happily consuming Butters’ semen.