|Friends/Allies||Gustav, Snotlout Jorgenson, Hiccup Horrendous Haddock III, Hookfang, Toothless|
|First Appearence||Defenders of Berk – "The Flight Stuff"|
|Last Appearence||Race to the Edge – "Gone Gustav Gone"|
Fanghook is Gustav's new dragon appearing in The Flight Stuff. He is a yellow and purple Monstrous Nightmare. Although he was supposedly released into the wild, he still sees Gustav every day to train with him.
Fanghook has the characteristics of a normal Monstrous Nightmare; although he is seemingly kinder and gentler than Hookfang, he is still brash and somewhat arrogant. He is seen to be easily intimidated by Hookfang when they first met and more compassionate to Gustav than Hookfang is to Snotlout most of the time. Although meeting Gustav for only a day, the dragon and boy quickly bond together enough for Gustav to ride him, making the dragon somewhat protective of him. He has an undeniably strong sense of loyalty towards his rider, as he merely waited for Gustav to call him, after he was 'released'.
Defenders of Berk
Fanghook first appeared when Gustav was looking for his own dragon. After rejecting the Terrible Terror and the Deadly Nadder, he found Fanghook chasing boars, picking him because Snotlout described the Monstrous Nightmare as "the most lethal dragon in the known world." However, due to Snotlout's "training," Gustav's relationship with Fanghook was like Snotlout and Hookfang's.
Gustav decides to head to Outcast Island after overhearing about the scouting mission from Trader Johan. The two easily get captured in Dagur's new trap, but are soon released by Hiccup. They then work with Snotlout and Hookfang to save Hiccup and Toothless.
The next day, Gustav releases Fanghook back into the forest. After Hiccup and Snotlout leave, Gustav calls his dragon and the two continue training together in secret.
Race to the Edge
Fanghook continue his training with Gustav and went with him to meet up with Hiccup and the other Dragon Riders.
Abilities and Skills
Having the average Nightmare abilities, Fanghook was able to learn some skills in one day.
- Intelligence: This shown great intellect for his kind that he was able to learn two types of orders from his trainer that are very useful in just one day, although going through some failures. He even shown to be much smarter as he was able to understand Gustav making fun of Hiccup by laughing and able to take out a fire.
- Evasive Manners: Like most Nightmares, Fanghook is quite agile and flexible, as he was able to dodge the arrows of the Berserkers and Outcasts with ease.
- "Fire It Up": Gustav's battle cry: Which he ordered Fanghook to Fire Burst and to release his fire. Unlike Hookfang, Fanghook obeys his command immediately.
Gustav Larson: When Gustav was denied membership to the Academy, he went into the forests in order to find and train his own Dragon. After rejecting a Deadly Nadder and some Terrible Terrors, he stumbled upon Fanghook. Though they had a rocky start and weren't the best team, they still care greatly for one another. After this, Gustav 'released' Fanghook back into the wild, though they kept training in secret. Their bond grow even stronger for past three years as they become closer. As they even have preety close personalty. Fanhook even shows better flyer to be better sync than before as they train even harder to become better team.
Hookfang: Upon the first meeting, Hookfang showed a certain disdain and hostility towards Fanghook, successfully intimidating Fanghook. However, this eventually became less and less, to the point they were willing to work together.
Toothless: Fanghook showed his wild personalty to Toothless, who seems to know he is potentially dangerous to other dragons and riders. While they were training, Fanghook tried to blast the target just like Toothless did, but he missed and almost hit the other riders which made Toothless roar at him in anger. Later, Fanghook was able to get his confidence thanks for Snoutlout and Hookfang, and was able to help freeing Hiccup and Toothless from Dagur. As shown three years later, Fanghook return slaps Toothless face by accident and came close to nudge him in his face but was push away by Toothless. As Fanghook even shown to be annoying Toothless by standing on his back.
Stormfly: Like his rider who has major crush on Astrid he shown to be interested in Stormfly. But possible he has been treated the same as Astrid treats Gustav.
- Fanghook's name is a play-on the name Hookfang (Snotlout's dragon).
- Fanghook's coloration is similar to the Monstrous Nightmare Astrid trained on Outcast Island when she was pretending to be Heather, and may be the same dragon. His coloration is also similar to that of Girl Hookfang, a Monstrous Nightmare that lives on the Dragon's Edge.
- Fanghook is the only known dragon on Berk to be training outside the Dragon Academy.
- Fanghook is shown to be smaller than Hookfang, and may well be younger or simply smaller.