I'm surprised most are discrediting the "midcard guys" Correct me if i'm wrong on this, but wasn't battle of the billionaires the most hyped mania match at 23, and who did that feature....UMAGA, and Bobby Lashley. See, at WM they make stars, and why would the wwe want The Rock to beat someone like Cena, HHH, HBK. Its doesnt make sense. Hell, Rock vs ORton makes sense, although Orton is a guy who needs to win a few big matches, not lose every one.
Which brings me to the list of midcard guys. Sure, no one wants to see Rock/Umaga, but i believe they are related thus it making sense for them wanting to wrestling each other. Then theres Mr. Kennedy. The guy is going to be a star, he is the type of guy who can lose to the rock, and still come a bigger star than before. Then theres MVP, very similar to Kennedy. I think either of these guys would be good choices. I just dont think the wwe would have the Rock headline mania, but for one match. If he were to return full time, yes i could see him headlining. Anyways...I believe they are leaning towards something like this for mania...thus they will have to work around this.
Cena vs HHH
Edge vs Taker
HBK vs ORton
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Rock vs _____ (Kennedy, Umaga, MVP)