#2 Brock Lesnar
Brock Lesnar wasn't considered unbeatable for a long while, but all that changed when he defeated The Undertaker at WrestleMania 30 and broke the legendary streak. The Beast suddenly turned into one of the most dangerous athletes of all time, and WWE made it a point to bring his UFC past into the picture and treat him like a legit fighter.
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Lesnar went on to squash John Cena in the main event of SummerSlam 2014 to win the WWE World Heavyweight Title. Since then, Lesnar began getting treated as someone who couldn't be beaten unless there was a controversial finish to the match. Lesnar went on to defeat the likes of Seth Rollins, Dean Ambrose, AJ Styles, Randy Orton, Samoa Joe, Daniel Bryan, and Braun Strowman. He ran roughshod over the WWE locker room and recently won back the Universal Title by cashing in his MITB briefcase on Seth Rollins.