Gunner is being built up well. Having crashed the ceremony and caused the havoc he did, but I don't think he'll take the strap off of Magnus. I see them going for a couple of title matches, I say screw him out of the first then have him win the next win in a special stipulation like a cage match on his own to prove himself. Afterwards, there are plenty of possibilities. There are Austin Aries, Samoa Joe, Bully Ray, Bobby Roode and much more. Personally, I would like to see Austin Aries go up against this new power. He played very well against Bobby Roode a couple of years ago, plus it'll push him away from the X Division. Not that the X Division is a bad place, but personally I want to see him in the main event scene.
Samoa Joe could also be one I would mark for. Have him choke out Ethan and Rockstar Spud a few times, which I will laugh. They also have a lot of history together, being tag team champions and even winning a tag team tournament a few years back in December 2011. I think they should save this feud though for a little bit longer, that way it'll add more suspense to it and more in the question of Magnus losing the belt.