Heartless
Heartless is a rouge brother of Toothless, and the true murderor of Grimoors the Nasty Mouthed's parents. Heartless earned his name from his past victims that DIDN'T get mauled to death in honor of it's ruthlessness, remorseless, and outlandishly cruel acts against ANYTHING alive that is beyond even the standerds of normal rouges. Heartless suffers from an animalistic illness that makes him endlessly wild and ferious, basicly, he's mentally rouge. He's a danger to even Nighthorrors. It has been known to burn down villages from having a small fit of rage, destroyed 10 of the largest gallions of the spanich trade, even Skuldrons are tormented by the creature. It's rouge mentality has also some, strange mutantions, like longer teeth, and still maintaining flight dispite years of battle damage, and strange eye color. Heartless has many features that OBVIOUSLY prove it wasn't toothless, but Grimoors is just too stubbern and stupid to realise it, especially since, because the two are related, they both have similar scent, which causes Grimoors to confuse Toothless for Heartless, unaware of what he presently looks like. It's been rumored that the engery of The Heartless themselves has long processed Heartless as a result of it's egg being exposed to dark engry, making it tecnecally an artifictal heartless, but the real history is MUCH, much more tragic. However, later on, after Hiccup and Toothless rescue him and he runs away out of fear, he ends up getting adopted by a Viking from a distant land named Burp, who, along with his friends, end up going the Monster Hunter Brigade, and after further getting rescued by Hiccup's Dragon Crew from Captain Firen Bluebeard at the cost of one of Burp's feet, Hiccup and his Dragon Crew give them advice to get along with their fellow dragons, and not only offers Burp a prosthetic foot like his, among other equipment, he ensures that he and Heartless will have a good kinship like he shares with Toothless, and advises him to be careful with where he flies. Thus, Heartless is now a rogue hero with Burp as they make a decent team.