#3 AJ Styles (2016)
Many fans were hoping for AJ Styles to debut at the 2016 Royal Rumble, but nobody actually believed it would happen. So when the words 'I Am Phenomenal' flashed on the titantron, the WWE Universe lost their collective minds. AJ's debut was a success.
Add in the fact that he was number 3 and set to have a delicious confrontation with Roman Reigns, who was defending his WWE Championship in the 30-man match, and Styles immediately felt like a player. Never has a debut as high-profile as this happened in the Royal Rumble match.
Charlotte Flair to return and wrestle a CURRENT CHAMPION?
The Phenomenal One would last around half an hour in the match, before having an unbelievable debut year in WWE. He capped off a stellar 2016 by winning the WWE Championship and having an excellent reign with it. One year later, at Royal Rumble 2017, Styles defended his WWE Title in an absolute classic against John Cena.
Whatever success he has had in WWE, some of the credit must go to the monstrous pop in that Royal Rumble. That was the moment that proved that AJ Styles was right at home in the bright lights of WWE.