There are different explanations for the origins of this beef — some say it was just another volley in the East-West rap wars, other reports suggest it stemmed from personal reasons — but Tupac and MB clashed as well. Pac famously lit into Mobb on "Hit 'Em Up," mercilessly dissing Prodigy for having sickle-cell anemia: "Oh yeah, Mobb Deep, you wanna f--- with us? ... Don't one of you n----- got sickle cell or something? ... You f--- around and catch a seizure or heart-attack / You better back the f---up before you get smacked the f--- up."
(Photos: Tim Mosenfelder/Getty Images; Raymond Boyd/Michael Ochs Archives/Getty Images)