User blog comment:IamJakuhoRaikoben/Chapter 503: The Last Sight Seen, Review./@comment-5303512-20160926122525/@comment-3290324-20160926124833

Because it's a nonsensical plot development, lol. The whole "Natsu turning into END" thing has been predicted for a long time, but once we learned END's history, it stopped making sense. :P