#8. Seth Rollins
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Seth Rollins mainly stood out in the Shield for his oddly colored hair, until he devised the Architect persona.
Still, he was second banana to Ambrose's intense personality and Roman's muscular physique. So it was actually pretty good planning on WWE's part when Seth betrayed the Shield to strike out on his own, gaining the WWE title in the process.
At one time, CM Punk had handpicked Seth Rollins to be a future main event star, and it seemed as if that prophecy had come to pass.
Seth gained instant heel heat, and his character blossomed into a more realized form than was possible while in the Shield stable. Now assured of his own main event Status, it seemed nothing could stop Seth Rollins's momentum.
Until he suffered a terrible leg injury and was forced to vacate his title. Seth missed many months of action and dropped down the card during the interim.