#4 Ric Flair
Probably the best wrestler ever and probably the guy that introduced the term "Cowardly Heel" into the business and took it to crazy heights.
One of the best on the mic and one of the best in the ring, Ric was the guy who lived his character and even during his matches he carried the heel persona with him. There's never been anyone like him who sold the moves as he did.
Even though Naitchhimself has had some memorable stints as a Babyface as well (especially the one at the end of his career where he kept getting hold of his opponent's "Stuff") but the stints that made Ric Flair the legend that he was, were his stints as the Cowardly Heel who would scratch and crawl and do anything he could to win.