#2 Rey Mysterio - 2018
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Perhaps the most surprising Royal Rumble entrant in recent memory, former WWE Champion Rey Mysterio entered the 2018 Royal Rumble match at number #27 to a monster pop.
The master of the 619 hadn't been since the post-WrestleMania XXX episode of RAW in 2014, losing to Wade Barrett. Rey spent the next four years making big appearances and making big money all over the world, which made his Rumble return that more surprising.
Rey lasted just under 10 minutes before being eliminated by Finn Balor. The crowd was electric during his time in the match.
After much speculation and another Royal Rumble appearance, in the Greatest Royal Rumble match, Rey finally came to terms with WWE on a new full-time contract in October 2018. It had seemed like for several months that Mysterio wouldn't be returning to WWE, but today he is back home on WWE SmackDown.