#4 Kevin Owens

Kevin Owens debuted on the main roster as a focused, hungry prize-fighter, but over the years he's lost some of that edge, and returning from injury to take out the Olympic Champion would be a great way to get that back.
There have been rumors that KO would be returning in a few weeks as a babyface, and that wouldn't require too much change in character, but ultimately, the sadistic KO that took out Sami Zayn in NXT is the best version of him.
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The other performers on this list all have some form of connection or history with Kurt, and while KO does not, going after him and taking him out is something his character would do. Owens hasn't been a singles star for almost a year now, so a big showdown with Kurt would give him the catapult he needs to get back into the main event scene, and while this is unlikely, it's certainly a great option for the WWE to consider.