- "I have one," grinned Snotlout, gesturing to the terrifying-looking, flame-red animal fast asleep in his basket. "I think I shall call her FIREWORM."
- ―How to Train Your Dragon
Ownership and Training
Fireworm is a large young Monstrous Nightmare specimen with bright flame-colored scales.
Fireworm is very vain and thinks highly of herself amongst dragons, even other Nightmares. She has great physical prowess. She shows no one loyalty, only when it is for her benefit. She does to brave deeds, but again only if those deeds pay off for the winning side. She also loves to sneer about stuff she hates, like Toothless.
- "That's not a dragon ... that's an ickle newborn bunny wabbit with a pathetic poo problem."
- ―Book 1
- Fireworm makes no appearance in the film; however, a Monstrous Nightmare named Hookfang is trained by Snotlout. Hookfang is the name of Stoick's in the books. Unlike his Fireworm, Hookfang is male and has a very different personality. Unlike Hookfang, Fireworm is very obedient towards Snotlout. Hookfang in the movie seems to show grudging respect towards Hiccup, whereas Fireworm in the book shows as much animosity as her owner towards him.