For Want Of A Nail: In How to Train Your Dragon: The Hidden World, Hiccup and Toothless encounter the Light Fury in the woods close to Berk, having been planted there by Grimmel as a sort of warning. Here, they encounter her on (what would have been) New Berk, the dragon simply out hunting but otherwise lives in the Hidden World.
Shout-Out: The chapter is named after the Blue Eyes White Dragon from Yu-Gi-Oh!.
