WrestleMania 40 has been fit to bursting with several surprises, but the main event has definitely had the biggest of both nights. Thanks to Cody Rhodes and Seth Rollins losing their match against The Rock and Roman Reigns, the American Nightmare had to fight for the championship during a "Bloodlines' Rules" match. To aid Rhodes in fighting back the Bloodline, John Cena made a surprise return to the ring and professional wrestling fans couldn't be more shocked by his return.