9. Eminem vs. Insane Clown Posse
This is one of those beefs that goes to show that you need to be nice to people you meet on the way up, because you will meet them again on the way down. In 1997, Eminem was a young, hungry, unknown MC, and the Insane Clown Posse were one of the biggest acts in the Detroit area. (Shocking, I know…) Eminem gave ICP a flier to his mixtape release party, to which they replied, “F*ck no, I ain’t coming to your party.” The end result of that negative RSVP was a series of verbal & physical attacks that resulted in arrests (for Eminem, after he attacked an ICP affiliate), crappy songs (from ICP), and the total decimation of the “Juggalo” movement.