Kofi Kingston

Of course, it wouldn't really be a Royal Rumble without a ridiculous Kofi Kingston spot.
The former US and Tag-Team Champion will perform his annual stunt, receive a big pop from the crowd, and then get quickly eliminated.
Ricochet

Like Adam Cole and Andrade 'Cien' Almas at last year's event, Ricochet will make a surprise appearance during this year's Royal Rumble match.
The reigning North American Champion is one of the hottest stars in NXT right now, and providing him with the opportunity to perform some sort of crazy stunt during the Rumble match will be a nice way to introduce him to the wider WWE Universe.
John Cena

Well, it wouldn't be a big match without Big Match John now would it? Cena's Rumble record is nothing short of excellent, and the leader of the Cenation will no doubt be given a strong run in this year's event as well.
Could he have an outsider's chance of winning the bout? Don't rule it out.