User blog comment:B214/Chapter 503: The Last Sight Seen/@comment-5303512-20160926122648/@comment-1776824-20160928171510

The other Etherious have had more than 400 years to curb their behavior and learn how to strategize, correlate and work together. Natsu has had his instinct awoken for the very first time. He's not going to stand there and go, "Oh shit, man, I should really kill Zeref." He has been in denial that he is E.N.D. from the very beginning of that encounter. Even towards the end he didn't really believe it, and didn't care even if it was true. He has been after Zeref thus far and tried to kill him not because he is an Etherious, but because Zeref has tried to kill his friends. Here, and right now, that is not the case. And honestly, you need to stop throwing "defend your statements" at me when I always present mine with fact, and super-duper definitely stop trying to refute my claims with speculation or theories. Fact is fact until otherwise. In an argument, facts are all that matter. Not hypotheticals.