Newtsbreath and Hookfang are in the chief's hut when Toothless wakes up. The two dragons greet Toothless and Hookfang swipes at Toothless, causing the little green dragon to howl in pain. Stoick then yelled at both hunting dragons to get out.
Newstbreath appears again in Book 2. Newtsbreath is revealed to not like baths as shown when he and the rest of the Hooligans get baths before going to the Isle of Skullions to search for the Treasure of Grimbeard the Ghastly.
Newtsbreath is a Gronckle, which is a tough, though ugly species of dragon. As such, he has a short snout and many spikes and protrusions around his body.
How to Train Your Dragon indicates that he is "about the size of a leopard" and has yellow eyes.
Newtsbreath somewhat fears Stoick due to the fact that he is bigger than him. Because of this Newtsbreath obeys Stoick when he yells at him.
Newtsbreath is prone to bully Toothless as he doesn't like him and Toothless is much smaller than he is. Toothless ends up sleeping in bed with Hiccup every night instead of at the hearth, as there is a real concern that Newsbreath and Hookfang might eat him.
Newtsbreath appears to respect Hookfang and appears to be his friend.
Newsbreath is introduced in Book 1, when meeting Toothless for the first time.
- "Newsbreath and Hookfang, Stoick's hunting dragons, came padding into the room. Toothless stiffened as they paced into the room. Toothless stiffened, their yellow eyes glinting evilly. Each was about the size of a leopard, and they were as delighted by his arrival as a couple of giant cats might be by that of a cute kitten"
- ―Book 1