The Game disses were classic. I can't think of any other rappers who were made fun of in more hilarious ways and got destroyed as hard during their beefs.
When regular rappers get dissed, the opponents usually give them some sort of credibility, calling them out on specific things, telling them they're fake and can't rap as well. With The Game it's straight up everyone saying he sucks dick, is a bitch and probably takes it in the butt.
The Yukmouth ones were golden: