He's been around so long and made such a name for himself it almost feels like he's already in the hall of fame. Mark began his career in the mid 80s and he spent most of that time jumping from one gimmick and one federation to the next. I first saw him in WCW when he was brought in as Sid Vicious' replacement in the Skyscrapers tag team. He was then known as "Mean Mark Callous" but despite the ability to walk the top rope and a boatload of talent never got completely over there. Then he was suddenly signed by the WWF as "Kane the Undertaker" and I was like "Are you kidding me? Vince McMahon has really bumped his head with that moniker."
At the time I didn't like the Undertaker character because it was the latest in this weird menagerie of made up trademarkable names Vince was trotting out at the time. Only top flight superstars like Ric Flair, Lex Luger, and Vader could go to the WWF in those days and not be given a whole new identity. By now most fans have forgotten about dudes like Bastion Booger, Sparky Plugg, Waylon Mercy, and Skinner. But Mark was one of the few who was able to take his new identity and do something remarkable with it. The Streak, several world titles, countless match of the year candidates, and his longevity are all testimony to Mark's greatness. Well done!