#2 The Undertaker
Anyone in the WWE Universe realizes that this has to happen. It makes perfect sense that The Deadman would take on the most terrifying entity in WWE since his debut all those years ago. Although it's unclear if and when The Undertaker will ride off into the sunset, this is a match that has to happen soon.
As The Undertaker gets older and isn't able to achieve the same kind of intensity in his matches, Bray Wyatt could offer a plausible route for The Prince of Darkness to pass the torch to a character that is worthy of carrying it forward.
Their match at WrestleMania 31 was a wash and didn't help the Bray Wyatt character at all. But things are different this time around. With the arrival of The Fiend, The Undertaker would take on someone who is far more deadly than he ever was.