Hiccup has received a strange book full of knowledge about dragons. Finding a potion that grants strength and the designs for a special arrow, he sets out to slay the Night Fury. Except now he finds himself slowly losing his humanity bit by bit... while simultianously changing the Night Fury into just an ordinary boy. And then things got even stranger.

AU. When the Vikings first came to the island of Berk, they killed almost all dragons that lived there, however, one of them made sure to leave a parting gift to the viking leader.