Please note this was written before Reigns relinquished the Universal Championship and before Ambrose turned heel.
It's a little early to predict the main event of Wrestlemania, but I'm thinking the Shield will have a triple threat match with the Universal Championship on the line. Dean Ambrose, Seth Rollins, and Roman Reigns have previously faced off in a triple threat match at Battleground 2016 in which Ambrose retained his WWE Championship over his Shield brothers in an exciting main event. That match was worthy of headlining Wrestlemania. It was odd for WWE to relegate it to smaller pay-per-view in the middle of the summer. Wrestlemania 35 will be the stage for the battle of the Shield round two. Here's how.
As I write this, WWE is building the card for Crown Jewel and teasing a Dean Ambrose heel turn. He most recently left Rollins and Reigns in the ring after being pinned by Drew McIntyre in a six-man tag team match that also featured Braun Strowman and Dolph Ziggler. I think Ambrose will turn into a full-fledged heel by the Royal Rumble but no earlier than Survivor Series.
If it happens at Survivor Series, I can see him snapping should the Shield lose a match or perhaps he costs his team and is the reason they come up short. Either way, he will be the one to break the Shield. He will then battle mainly Seth Rollins through the Royal Rumble while also having a few encounters with Reigns. I think Reigns will be Universal Champion at Wrestlemania, but how will both Ambrose and Rollins join him in the main event? I have two scenarios.
Option one has Rollins winning the Royal Rumble and putting his main event title shot on the line against Ambrose. The Lunatic Fringe will win the match via nefarious means and steal away Rollins' title match. Rollins will then be added to the match because of how Ambrose won and the Shield will be set up for a triple threat at Wrestlemania. Option two has both Ambrose and Rollins winning the Royal Rumble via a double elimination. Reigns, being the fighting champion that he is, will agree to face both of them at Wrestlemania and the Shield will headline WWE's biggest event of the year.
The question everybody will be asking is who will win this potential Wrestlemania 35 Shield triple threat match for the Universal Championship? We all know how the crowd reacts to Reigns as an individual star. While I wouldn't put it past WWE to have Reigns walk out with the belt, I feel like WWE will continue to push Reigns as an unstoppable underdog and having him lose the title will allow the company to continue to position Reigns in that role. Rollins has arguably been WWE's best in ring performer throughout 2018, and the crowd adores him. He gets one of the best pops in the company, and he will undoubtedly garner a huge reaction should he win. He's already done that however, as he walked out of Wrestlemania 31 with the WWE Championship. That leaves Ambrose. While all three have been World champs, Ambrose is the only one who has not won the title in a Wrestlemania main event and there would be no better way to solidify Ambrose as the top heel in the business by having him defeat his two former Shield brothers for the Universal Championship in the main event of Wrestlemania 35.
That's what I think will happen at Wrestlemania. The Shield will implode, Ambrose and Rollins will somehow both get a title shot at Wrestlemania against Reigns, and Ambrose will walk away with the belt. In my option, WWE has been doing a good job on teasing Ambrose's heel turn. It has been a slow build and hopefully the payoff is memorable. Should it lead to a Shield triple threat at the showcase of the immortals, then it could result in some of the best storytelling WWE has ever produced. If this is the route WWE is heading, I cannot wait to watch it play out on television.