#2 Random backstage attacks
Random attacks backstage are a classic way to make a character look dangerous. WWE have used it many times in the past and there is not a more relevant time to use it than on RAW Reunion.
Like mentioned earlier, RAW Reunion will include a lot of Superstars from the past, which means that it will have the attention of the fans. As a result, the premise of the show is huge and if WWE play it right, they can push Wyatt to the moon by making him look strong.
The easiest way to do that is if he attacks the legendary Superstars of the past backstage and makes them unconscious (or even when they are in the ring cutting a promo and the lights go out and then come back again, only to show motionless bodies lying in the ring).