Rey Mysterio is a human.
Rey Mysterio . He is also known for his work in Extreme Championship Wrestling ( ECW ) , AAA , and World Championship Wrestling ( WCW ) . `` Rey Misterio '' is Spanish for `` King Mystery '' , but subsequently dropped the `` Junior '' from his name when he began working for WWE in July 2002 until February 2015 . He was the 21st person to complete the WWE Triple Crown , and was the winner of the 2006 Royal Rumble .