User blog comment:FairyRaven/Fairy Tail Chapter 427: Pitched Underground Battle, Review and Commentary/@comment-1776824-20150407032850

Late Wrath is late. This chapter was stupid. One-shotting everything is getting real old. I barely got over Bluenote, and now a hyped organization is being fucked in the arse with Gray coming in and saying, "Oh hey scrubs, you can't beat this guy. Lemme get it on." Whatever.

To everyone saying Natsu's dragonification is progressing, Igneel and the others stated that they spent enough time in their bodies to create enough antibodies to permanently stop the progression of their transformation into dragons.

To everyone saying Natsu could be turning into E.N.D., Igneel greatly hinted that the only way this could happen was if the book was opened, and even went as far as to almost all but say that if the book was destroyed, Natsu would die. He even said, "Only you can do it," when he asked Natsu to take it. Mashima has alluded that his real power, true body and memories are inside that book, so him being able to tap into it is pretty ludicrous, considering the book is (for now) permanently sealed, and so is everything inside it.