User blog comment:FairyRaven/Fairy Tail Chapter 386: Galaxia Blade, Review and Commentary/@comment-4449950-20140530101058/@comment-4829046-20140530181046

I stick by my initial hypothesis when reading the chapter which is that Marde was petrified due to being of Darkness. Now here's where it gets tricky. There are two scenarios with this, one is that since it was Alegria that was rejected, then it makes sense that Marde, the one who can do all those is also rejected or else he could just use a similar spell again, another is that unlike the other Demons, Marde is truly rotten to the core and didn't get to that point artificially and can't exist on a lesser domain, which is why he stuck to his throne the whole time not giving a damn. Now before you say Keith or something, hear this, what if those are mere experimental Demons of the book? Maybe they don't embody evil, they just carry things out just cause their position states so while Marde is truly evil, like his very existence is made of malice.