#4 Samoa Joe
From the moment Samoa Joe stepped foot in WWE, business picked up.
Debuting as a face, the former TNA star would turn heel quickly, capturing the NXT Championship, and becoming the first man to hold the title twice.
Joining the main roster in 2017, Joe has been impressive, but despite high profile feuds, has yet to win either the WWE or Universal Championship.
That hasn't stopped the company from teasing this, as Joe feuded with Brock Lesnar for the Universal gold when the Beast was champion, and with AJ Styles during his year-long reign as WWE champion.
The current United States Champion, the spot on top of the mid-card is a good place for the Samoan Submission Machine, but there is no shortage of fans who feel that Joe could become a top heel Champion.