Last but not least, Francisco Filho, Glaube Feitosa, Sam Greco, Semmy Schilt, Bas Rutten, Andy Hug - all fighters with a strong Kyokushin background who seemingly have had no problem adapting to kickboxing or MMA rules. Before anyone says "Well, Bas Rutten only did Kyokushin for a while before he started doing Muay Thai" I'd like to point out that he's a 5th dan black belt and credits Kyokushin as the foundation for his kicking on one of his DVDs (sorry, can't remember which one). A 5th dan in Kyokushin takes many years, and most people never progress above 3rd dan - Rutten obviously continued doing Kyokushin even after he started Muay Thai as well.