CM Punk never won a Royal Rumble, unlike most other major headliners in the business. This perhaps bothers Punk more than we realise, he did after all take off from WWE the night after Royal Rumble 2014, maybe he was annoyed that he was yet again being overlooked for the winner spot. It's something missing from Punk's resume, an achievement he could be tempted back for. Say if WWE offered Punk a Royal Rumble win whereby he would then go on last at WrestleMania 31, he would then be able to achieve two dreams at once. It's a deal WWE could absolutely get Punk back to work with. The way it could happen would be the ultimate comeback. Don't advertise Punk, don't let it leak a deal has been done. Instead, as the number 30 entrant timer counts down at Royal Rumble 2015, hold for a pause. Then hit the Punk music. Coming out as the final man would be the biggest Rumble pop ever. He would enter the ring to eliminate whatever heel has been dominating, winning the Rumble and pointing to the WrestleMania 31 sign.
