Originally Posted by ACt
I guess there really is no getting around the idea of Natsu going back in time with Lucy to become the guy in that mural we saw a few times. He's headed back to fight Zeref which is why the current Zeref knows who he is. We may possibly get Zeref just killing everyone at the contest which forces their hand, which would be kinda cool.
What if... Natsu is originally Acnologia?