#4 Sting (2014)
If AJ Styles spent his peak wrestling years by working for all the promotions but WWE, Sting spent almost the entirety of his career by working for wrestling promotions not named WWE. It was every fan's desire to watch Sting on Vince McMahon's turf, but Sting had, for long, restrained himself from working for WWE due to his own insecurities.
The Face of WCW waited for nearly 14 years after the death of the promotion to appear for WWE, and, in that period, worked for probably every other wrestling promotion in the whole world while increasing the curiosity of fans who wanted to see him work for McMahon's company.
And then, the day finally arrived, in the fall of 2014. With Triple H using his power to force the referee to count the pinfall after his illegal interference in the all-important Authority vs WWE match, a cawing of the crow interrupted the count as the fans went into a state of frenzy. A few minutes later, Stinger was finally standing in Vince McMahon's yard, in front of his own son-in-law.
Not only did Sting start a feud with Authority that night by knocking HHH down and costing Authority the match, his actions brought a temporary end to the reign of Authority. Even though Sting only wrestled two high profile matches for WWE in the coming 12 months before his retirement, his debut was one of those surreal moments where one traveled back to the time when he was the Icon in WCW.