#2 Rey Mysterio

Rey Mysterio is still considered the Ultimate Underdog, and why not? Not many of his stature have achieved the kind of success he has. In 2006, when Mysterio against all odds won the Royal Rumble, it was a match made in heaven.
Everyone was awaiting the coronation of their favorite underdog. The 5'6" superstar gave the WWE fans their money's worth when he emphatically won the WWE World Heavyweight Championship at the WrestleMania 22 main-event, after beating not only Kurt Angle, but also 'the Viper' Randy Orton, in what was an instant classic.
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With Vince McMahon generally backing strongly built superstars, Mysterio's win was a breath of fresh air, which also broke the stereotypical thought of WWE not investing in their cruiserweights.
The charisma and determination of Rey did stand out over the course of the storyline, which makes this one of the best in the WWE.