With this new chapter it can almost be confirmed that Law is the one creating there weird beasts. What I am wondering is what happens with the leftover? Brownbeard and the rest of the centaurs had legs at one time and the animal bottoms had tops. Are the extra part being used to make a body for the gas/liquid guy we saw earlier? What do the people of the wiki think?
Also that Brownbeard is quite the guy. He's faced Hawkins, Law, maybe Blackbeard and now Luffy and he's still alive(although he now seems to be a follower of Law).