13. The Fat Tony/Fit Tony Thing - "Donnie Fatso" (22.9)
Here's certified proof that by the 22nd season, the writers weren't bothered about preserving the integrity of the show any longer. Which is to say, Fat Tony is killed off in "Donnie Fatso," only to be replaced by his cousin, Fit Tony, who - by the end of the episode - sounds and looks exactly the same, and is even renamed "Fat Tony." It was supposed to be funny, but it was actually disrespectful and shocking. Way to ruin an iconic character for absolutely no reason.
Sam Hill is an ardent cinephile and has been writing about film professionally since 2008. He harbours a particular fondness for western and sci-fi movies.