#3 Hade Vansen
Now this has always been a very interesting talking point for fans, and for years, it was one big mystery.
Hade Vansen was an English professional wrestler who signed with WWE in 2007. He was pretty talented, but what caught WWE's eye was his gimmick, which can be described as being similar to Christopher Daniels 'Fallen Angel'. The idea of bringing him up was said to be from Michael P.S Hayes, and with his main priority being fresh blood for a lengthy feud with The Undertaker. Vince McMahon apparently liked the idea originally, but soon soured.
Apparently the plan was for Vansen to have a major feud with the Deadman, which would have seen him begin his own dark faction, joined by Kevin Thorn, Big Daddy V and developmental performer Black Pain. It reached the point where they would air vignette for Vansen talking about how he loved the darkness and had his followers who he had shown the way. He also made reference to The Undertaker, without mentioning his name, saying he required his immortal power.
Just one week later, everything was dropped. Apparently Vince McMahon didn't see much coming out of it in the long term, and also may not have been a fan of Vansen's stature. Vansen would be released from WWE in January 2009 and no one has heard much of him since.