User blog comment:IamJakuhoRaikoben/Chapter 451: Fairy Heart, Review./@comment-5268982-20150907084025/@comment-11589080-20150907085317

I think Fairy Heart is not just an infinite source of power. From my understanding of the chapter, it's a Magic akin to Face and Etherion, but one that is limitless. Also, from the prior knowledge that it is superior to the Three Great Fairy Magics, it's probably one bad-ass spell.

Another thing, I think Natsu is hiding scales underneath those bandages, like legit dragon scales. We've been teased about his dragonification for a while now and maybe this is it.