#6 That's gotta be KO

Of all the possible storylines we've compiled in our discussion, this, along with the possibility we spoke about earlier which sees KO re-join The Authority are perhaps the second-most likely ones the WWE is going to present us with.
Braun Strowman recently handed over his Money In The Bank contract to "Constable" Corbin on RAW--noting that he intends to challenge reigning WWE Universal Champion Roman Reigns at the Hell In A Cell PPV on September 16th. The WWE has officially announced the Strowman vs. Reigns for HIAC; as the Universal title hangs in the balance between these two titans.
How Brock Lesnar ruined another wrestler's career - Watch Now!
Having been squashed by the aforementioned Strowman at SummerSlam on August 19th, Kevin Owens now has a golden opportunity to avenge the merciless beat-down that The Monster Among Men laid down on him. The WWE could book Owens to interfere in the Universal title match--attacking Strowman and thereby costing him the title.
Remember when Kane cost The Undertaker his Hell In A Cell match against Shawn Michaels? Yep! KO could exact vengeance upon Strowman in a similar manner, albeit with the additional threat of Reigns looking to Superman-Punch The Monster into oblivion...
A top WWE star is missing in action