#10 Roman Reigns and Dean Ambrose helping Seth Rollins to defeat Brock Lesnar for the Universal Championship
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In order for the Shield to make a momentous return at the Grandest Stage of Them All, Seth Rollins' bout with Brock Lesnar definitely has to be a No-Disqualification.
While I genuinely want the Architect to curbstomp the Universal Champion out of the main event picture, there's no way he could do that clean in the main event of WrestleMania.
Stronger men have tried and stronger men have failed. This is not a dig at Seth Rollins because he is possibly the most talented member in the entire Shield.
However, defeating Brock Lesnar clean is something that would possibly diminish his credibility as a box-office Beast, and this could coerce Vince McMahon to make a clinical decision in order to send the fans home happy.
The Big Dog returning alongside Dean Ambrose to get their hands on the Beast Incarnate at the Grandest Stage would be a solid way to propel Rollins and give us a fantastic WrestleMania moment with the Hounds of Justice closing the show to deafening reaction.