There aren't any. Guns and knives aren't allowed in the UFC, and the only use for crescent kicks is to kick weapons out of people's hands. And then only if you're Chuck Norris. Are you Chuck Norris?
This is an awesome answer. I can just imagine all the rubber knives and wood gun blocks flying around the McDojo.
To the OP - they just don't generate enough power. People like to say that about a lot of TMA kicks, but usually it's not true. They usually just sacrifice some power for speed and accuracy. However, in the case of the crescent kick, it's just an odd attack that really only works to slap someone across the face. It can be used for an axe kick set up, or turned to dig into the body for a weird front kick variant, but just the classic sweeping motion, I doubt you'll ever see really applied unless a guy is just trying to show off.
You see them cause KOYou can get knock out force with them, just not easy.
You see crescent and axe kicks all the time, probably an average of 1 per event. The reason no one can think of a time when they saw it is because they are relatively useless.
One of these days someone is going to land one clean and get a KO, then you'll see everyone throwing them like 3 per fight.
1 per event? what events? low level MMA?
I watch pretty much every fight of UFC PPVs and all the main card fights of the lesser UFC and Bellator events and don't think I see a crescent kick every event. certainly not axe kicks.
The last time i saw an axe kick in high level MMA was by Cung Le, the time before that was Cro Cop vs Mark Hunt.
1 per event? what events? low level MMA?
I watch pretty much every fight of UFC PPVs and all the main card fights of the lesser UFC and Bellator events and don't think I see a crescent kick every event. certainly not axe kicks.