There's been this AU floating around my head lately about the Big Four going dark and turning into evil elemental versions of themselves, and I'm not sure what I'll do with it, but for now, here is some fanart. Yeah, I know, it looks like a comic, but nothing's solid yet. :3
Loosely based off of dragonlordhiccup.tumblr.com 's design, but only the design, I'm not shipping him with anyone and I've made a different backstory.
When Hiccup made the decision not to kill Toothless, the choice was so huge that it created an alternate reality where he did
kill Toothless. This dark!Hiccup is a result of that other reality. The Night Fury's soul latched onto his own as it died and created the monster he is now. He's bitter because of the other Hiccup's success and popularity while he himself rules a land of desolation. He can communicate with dragons and is practically one of them now. He's been trying to hunt down the other Hiccup ruthlessly for his own shadowy motives and desires.