South Park closed out the season with one of the most offensive and racist things they've done in quite a while, Cartman's "Not My Waterpark" song. But God help me, I thought it was hilarious. (I suppose I'm one of those minorities Cartman prayed to God to have ejected from his water park.)
Not to mention everyone peeing on monkeys and then on Randy Marsh. To this day, I'm amazed at what South Park can get away with.
The rest of the episode with Kyle's hatred of pee and how he had to suffer for it was really good. The 2012 parody was funny. As Mr. Pi Pi, Trey Parker does the worst, and that is to say the best, Italian accent I've ever heard.