#4 Mankind
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Mick Foley did many things in his long career, during which he successfully managed to pull off three different characters. There was Dude Love, Cactus Jack, and the most successful alter ego, Mankind. Mankind defeated Undertaker clean on the King of the Ring pay-per-view in 1996, the same show where Steve Austin cut the infamous Austin 3:16 promo.
Mankind then defeated Undertaker at SummerSlam 1996, in the Boiler Room Brawl match. This was after Paul Bearer turned on Taker, and sided with Mankind. Then, in October of 1996, he beat Undertaker again, this time in a Buried Alive match. The show was fittingly called, In Your House 11: Buried Alive.
#3 Stone Cold Steve Austin
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Stone Cold Steve Austin is the most popular wrestler in WWE history, so as you can imagine, he was pretty successful.
Austin beat The Undertaker in the main event of SummerSlam 1998 to retain his WWE Championship. After the match, The Undertaker handed the belt to Austin, and nodded as a sign of respect. But by 1999, there wasn't any respect between the two men.
The Undertaker won the WWE Championship from Austin at Over The Edge 1999, after help from heel referee Shane McMahon. Austin won the title back from The Deadman, just over a month later on Raw. On the June 28th, edition of Raw in 1999, Austin hit the stunner on Undertaker and once again, he became WWE Champion.
Did a WWE Hall of Famer predict John Cena's heelish ways long ago? More details HERE.