#1 Daniel Bryan

How can anyone possibly forget the epic Yes Movement that took over WWE in 2013 and 2014?
Daniel Bryan was always perceived to be an underdog, he didn't stand at 6 feet or weigh over 250 pounds, but he did make it up with his superior in-ring ability.
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Bryan had his fair share of ups and downs before his feud with the Authority. But it was the onset of the Yes Movement which saw Bryan scale unprecedented heights.
After Triple H turned on Bryan, causing him to lose his championship to Randy Orton, Bryan went on an epic storyline that saw him needing to win a match against Triple H first to earn a spot in the main event for the WWE Championship.
He did that successfully but was heavily injured, making it seemingly impossible for Bryan to even compete. But Bryan being Bryan did the unthinkable when he won the championship, and made the crowd go wild like never before.
The storyline is perhaps the best in the PG era, with the WWE fans invested in the idea of Bryan winning the championship.
While Mick Foley and Rey Mysterio could have clinched the top spot as well, Daniel Bryan's winning the championship against all odds makes it the best underdog storyline in WWE history.