User blog comment:IamJakuhoRaikoben/Chapter 411: Quid Pro Quo, Review./@comment-4449950-20141201232911/@comment-25111584-20141203085630

@Nick:- Ummmm, just a few points:
 * Memento Mori is a Curse by itself, it's not a part of Thorn Curse. And I don't think it even has an element. Not all Curses or Magic need to revolve around some element or another.
 * Slayers are supposed to eat elements, magical or not. But they don't eat just any kind of Magic or Curse.
 * I'm pretty sure Curses are not limited to Demons, it's just that E.N.D. developed them, so he taught it only to a few of his select people (no idea when he did all of this and fought Igneel considering he was supposed to have been sealed inside the book since he was created ... or did I miss something?). Galuna Islanders and Lullaby used Magic, no Curses. Pretty sure Deliora too. And Curses can most probably be used by other beings too, just like Demons can use Magic. Mira was able to Take Over Macro because Sayla was using it, she was able to take it over through her, not because it's demonic magic in itself ... or at least that's what I think. >.>
 * Also, from what Mard said, Gray's blackening/demonification was more of the reason that Mard's attack was negated rather than it being a result of Gray blocking his attack. But this is just speculation. Pretty sure we'll be told what happened to Gray's body when Natsu asks him about it.

Actually, I thought something more on these lines occured:
 * The Mira vs. Sayla shows that Curses are not as effective against humans using demonic Magic (not Demons themselves), like Gray and Mira. In some cases, where the Curse and the Magic are also extremely incompatible, they can even negate each other. Memento Mori was pretty strong, so Gray had to demonize half his body to block it.
 * This was also most probably (Stream says "It's finally complete," which is much more convincing than panda) Mard's first successful casting of Memento Mori ... until he was proved wrong by Gray. Guess he got pretty frightened when he realized he was gonna wake up E.N.D. and have almost nothing to show for it. ... And then got enraged.
 * Putting this together, it made sense to me. But well ... *shrugs* just my interpretation of how things went down.

All that said, still didn't like the Chapter, even though it made perfect sense to me and had no real nakama BS. Dunno why. >.>