#6 Edge
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In 2007, on the May 8th, edition of SmackDown, Edge defeated The Undertaker for the World Heavyweight Championship. This was after he cashed in his Money in the Bank contract. So it wasn't really a match, but technically it was.
The two men then faced each other at One Night Stand 2008 for the championship, this time in a TLC match. Edge put Undertaker through four tables and grabbed the championship from the top of the ladder. Losing the match meant Undertaker had to leave the company, but that obviously didn't last long.
#5 Triple H
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Much like his best friend Shawn Michaels, when you think of Triple H and Undertaker, you think of WrestleMania. Undertaker beat Hunter at WrestleMania X-Seven in 2001, and then two WrestleManias in a row. First, in a No Holds Barred match at WrestleMania 27, and then a Hell in a Cell match, at WrestleMania 28.
But Hunter has beaten Undertaker on a couple of occasions. Hunter beat Undertaker first on an episode of SmackDown in 2000. It was a No Disqualification match, and he won after Kurt Angle 'accidentally' hit Undertaker with a sledgehammer.
Another win for Hunter against Undertaker came in 2002. The pair met in the main event of WWE's United Kingdom pay-per-view, Insurrection. Hunter won the match clean after hitting the pedigree.
Did a WWE Hall of Famer predict John Cena's heelish ways long ago? More details HERE.