Up #1: Royal Rumble 2020

McIntyre entered in at #16 in the Royal Rumble match, and confronted Brock Lesnar to a loud pop. A sneak attack by Ricochet led to McIntyre throwing Lesnar out of the ring to a thunderous response from the live crowd.
He went on to win the whole thing after eliminating Roman Reigns, thus bagging a guaranteed shot at the top title at WrestleMania 36. The only thing that would trump McIntyre's Rumble win would be him winning the WWE title at WrestleMania 36, by putting down The Beast.
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Down #1: The formation of 3MB

Although McIntyre had already lost a ton of steam by this point, him aligning with Heath Slater and Jinder Mahal was the final nail in the coffin. 3MB went on to become mainstays in WWE's lower card, and things never took a turn for the good again.
McIntyre finally exited WWE in 2014, and would come back in a completely new avatar three years later.