The man who would go on to become WWF's 'The Undertaker' was nothing more than a WCW undercard talent from 1989 to 1990. He wrestled under the name Mean Mark Callous, working under Teddy Long and later Paul Heyman. Even back then he appeared to be a great pro wrestler, a fantastic look and athletic in-ring skill. If you track any videos down you'll see he was popping off dropkicks as well as the WWF moveset which would later make him famous, utilising manoeuvres such as the rope walk into the shoulder blast. For whatever reason though, WCW weren't impressed. They declined to renew his contract. This is surprising, surely they could see at 7 feet tall and 300 pounds they had a marketable star on their hands? And what about the great athletic in-ring work? Undertaker has since stated he was unhappy there anyway, he didn't like how the brand was run. He ended up coming to the WWF where Vince McMahon recognised his talent and cast him in the mega-push Undertaker role. Perhaps scorned form his WCW days he ended up becoming WWF to the core, acting as the locker room leader, hating WCW with a passion. The only conclusion we can make is that WCW let the most enduring star of the last three decades go, which is quite frankly wholly unforgivable.