User blog comment:FairyRaven/Fairy Tail Chapter 398: The Final Duels, Review and Commentary/@comment-7418318-20140901145939/@comment-66.87.125.186-20140901190631

Same Lunatic pretty much took the words out of my mouth.

I would say to you, nick, that there's no need to be worried. Just because he's stronger now doesn't mean that Gray has become a member of the one shot club. I always loved Gray's fights because he always found himself thinking outside the box to get his win. I don't see that changing just because of his power boost. For that to happen, every enemy Gray fought would have to be a Demon. Which I'm sure they all won't be after this arc. So don't worry. But if you want Gray's powers to disappear, then you might be out of luck on this one. There's no way Mashima will take away Gray's demon slaying magic, especially considering it's basically a gift from his dead father. And personally, I'm okay with that!

Also, to the guy who mentioned how Dragon slayers couldn't beat Dragons: the GMGs taught us a couple things about dragons. First, non dragon slayers have absolutely no chance against a dragon. Second, the Dragon Slayers, while they did manage to hurt them from time to time, couldn't actually defeat any of them. Dragons are incredibly strong.

In this arc, it's been shown that non-devil slayers can defeat demons. And in the case of Laxus v. Tempesta and Natsu v. Jackal, they were pretty convincing wins. So it's not surprising that a Devil slayer could completely annihilate a demon if he/she really went in on one like Gray did with Tempesta. Demons are strong, but not Dragon strong.