I personally believe that moria is either on teach's crew or
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I think luffy will have to fight against blackbeard's crew at some point and i think thats when the grand fleet will come into play too (or maybe against the world gov.) but i also think thats when luffy and shanks are gonna meet up and i personally believe that they will fight blackbeard together.
My only reasoning for this is becuase shanks had a hard time fighting blackbeard before the whole two devil fruits mess, so i can only imagine it'll be a two person job after the fact. i wanted to post this to see what other people think and how the fight against blackbeard will go