#4 Sting - The Undertaker
Sting and The Undertaker are past their prime, but no one can deny the fact that a match between them can sell out any arena. Both Superstars were iconic figures of their respective promotions in the 90s, and very few fans expected Stinger to join WWE.
However, WWE got him onboard in 2014, and he made his first WWE appearance at Survivor Series that year. He soon engaged in a rivalry Triple H, who later challenged him to a match at WrestleMania 31. Unfortunately, Sting could not win that match. However, he then challenged Seth Rollins for the WWE World Heavyweight Championship at Night of Champions.
Much to the disappointment of the fans, an unfortunate botch during that title match resulted in an injury which forced Sting to end his career. WWE soon inducted him in the Hall of Fame. He has not wrestled a match since, but he has mentioned in interviews that he would not mind coming out of retirement to battle The Undertaker.
Speaking at a live panel on Fite TV, the Icon said:
"I mean, everyone knows who it would be. Taker, he’s the only guy I’d come out of retirement for now. No one else. We could just never get it together to make it happen. When I started talking to WWE he was booked with Brock and then I did the deal with Triple H and he had another feud going on at the time, so it was just one of those things we couldn’t make happen."
Given that Sting celebrated his 61st birthday a few days ago, it is unlikely that we may see this dream match in WWE.