Story idea's (cause i can't write full story's)
1 HTTYD with demons instead of Dragons a bit of magic and future tech being created by Hiccup(with the nickname Hunter) on top of That, Hiccup leaves Berk and finds a crew with Who hé wil Make a base and fight demons with, and of course to make it all a bit more interesting Hiccup is part demon
Fore example: Hiccup leaves Berk cause he's done with their shit, and finds a cove with a cave, in that cave hé finds a book and a crystal the book is bleu and green, but when hé picks it op it turns black and red the book contains spels and bleuprints, these bleuprints are from little planes so Hiccup starts learning hoe to controle and use his demon powers, hé also Learns that the crystal hé found is a energie source that wil keep a little plane flying ,so hé starts constructing a plane hé that hé calls the groncle with this hé leaves the island of Berk, and finds a bigger and uninhabitat island that the Vikings stay clear of because it is to high for them to reach. On his new island Hiccup creates a home for himself and here hé learns that hé can create portals , so hé uses those portals to go to other villages to trade for materials that hé Needs, and on his trips hé saves Some people who become his team in his mission for revenge on both the demons and Berk.
(If anyone wants to make this story i would be very happy and if you need some help with what Hiccup and his crews base should be look op SE super heavy drone carrier it's a ship created by a tallented builder in a game but it still looks awesome)