http://onepiece.wikia.com/wiki/Pica

The prevalent belief is that he's a paramecia type, which makes sense considering that he seems to manipulate the stone, rather than become the stone.

Kinda nice that Zoro gets to continue where he left off with his fight, though I feel like a guy who creates fists the size of small villages and punches things doesn't really fall into the group of bad guys that Zoro would likely face off against, big sword or not.