User blog comment:Miskos3/Fairy Tail Chapter 506: The Broken Bond, Review/@comment-24784846-20161018172631/@comment-7418318-20161020122244

1) E.N.D.'s purpose (if he has one beyond reviving the dead body) is to kill Zeref and only Zeref. As long as nobody gets in his way like Gray, he has no reason to kill anyone who isn't Zeref. So having Natsu want to kill everyone would be OOC for both Natsu himself and any second END personality, if there was one.

2) He probably means Gray, who IS acting contrary to his established character. Yeah, yeah I know, you don't need to mention the corruption again, I am aware of that, but that doesn't change the fact that he's currently OOC.