Katsunori Kikuno is a former Kyokushin karateka who trains at Tsuyoshi Kohsaka's Alliance-Square gym and is also mentored by "TK." Kikuno's trademark skill is a karate kick to the liver, somewhere between a front kick and a roundhouse. It's called the "mikazuki geri," or "crescent kick."
Why has this kick received so much attention? Because it can be used to counter takedown attempts.
Kikuno used a Sanchin (or hourglass) stance against Koichiro Matsumoto in their Deep lightweight title fight, so we're beginning to see the mixture of karate and MMA in his game.
The Sanchin stance basically killed Matsumoto's in-out stepping tactics. When his arms moved forward, it left a perfect opening for a superior kicker like Kikuno.
Big thanks to Chris Nelson (from Bloody Elbow) for English and editing.