#1 Muhammad Hassan (WWE SummerSlam 2005)
WWE came extremely close to making a huge booking decision that may have changed the course of history, but some unfortunate happenings forced their hand to alter their plans. Muhammad Hassan was earmarked for significant success in WWE, rising to prominence as one of the most hated heels on the roster.
The real-life Marc Copani adopted an Arab-American gimmick, speaking about prejudice towards Arabs. He quickly became a top villain and entered a feud with The Undertaker in mid-2005, where the plan was for him to win en-route to becoming the youngest World Heavyweight Champion in history by defeating Batista at SummerSlam.
Copani confirmed that he had heard of plans for a world title win during a Q&A session as part of Sportskeeda's UnSKripted series.
However, WWE booked a segment on SmackDown, where Undertaker got attacked by five masked men. It aired on the day of the London bombings, and the company was pressurized to remove the Muhammad Hassan character from TV.
As a result, he was written off after taking a Last Ride through the stage from The Undertaker. Copani was sent back to developmental, before subsequently being released from WWE. He retired from wrestling and is now enjoying success as a school principal.