#4 Finn Balor turning heel and joining the OC
The former Intercontinental Champion, Finn Balor, has been a babyface for the entirety of his WWE career. So much so that fans have almost forgotten the guy who wreaked havoc alongside a certain "Club" that he formed in New Japan.
With the reports of him taking a break of two months after SummerSlam, it would be a perfect time for Balor to turn heel and make a massive return. AJ Styles turning heel and forming the OC has been a great decision from WWE, and they could one-up this by letting Balor join it as well.
A faction containing AJ Styles, Finn Balor, Karl Anderson, and Gallows has success written all over it, and the WWE writers should not let go of this golden opportunity. The storyline could go as far as them being out of control and destroying everyone on both the rosters, only for a certain faction to step up and fight with them to find out the undisputed (wink wink) top faction.