In recent chapters it's been discovered that the mark on Shank's eye was caused by Blackbeard. And I think it goes without saying thats not a scratch that a human would make. It seems to me that Blackbeard has some kind of zoan fruit power, and I'm willing to bet that his power turns him into a bear.
I don't know if this thread has been done or talked about before so please bear with me. (no pun intended...ok maybe just a little.)
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Ya know, when a man works hard his entire life enduring hundreds of ladies, many of whom he does not even remember you'd like to think that at the end of the day he will be given a lot of money, without having had to earn it. -Leon Phelps