Out of the modern guys, I'd say the biggest would be Sting.
Old school, and I'm not sure about all of them. So, correct me if I'm wrong.
The Original Shiek, the one who set people on fire.
Harley Race
Verne Gagne
Nick Bockwinkle
Mil Mascaras
Antonio Inoki
Dory Funk Jr.
Killer Karl Kox