Appearance
Hookfang is a Monstrous Nightmare, and is the size of a leopard in the books. In the movie he is 61 feet long with a 68 foot wingspan. In the books, Hookfang actually belongs to Stoick and not Snotlout. According to Snotlout, Hookfang weighs around 5,040 pounds, and he can light himself on fire using his sweat. Hookfang is a perfect example of a typical Monstrous Nightmare. He has large shiny grayish-black horns that curve slightly outwards on the edge. He has bright reddish-orange scales with darker spots scattered around. His underside is a light tan, and he has yellowish orange eyes like most other dragons. Hookfang is the most commonly seen Nightmare, so most stock images are of him. His color scheme is fairly common in the movie, and Snotlout has even mistaken other Nightmares for him. Hookfang's horns lack extra antlers coming off of them, which does help to distinguish him from other Monstrous Nightmares seen in the film. He seems to be fully grown, and no Nightmares have yet been seen that are notably larger than him.
In the Books
In How to Train Your Dragon, he mocked Hiccup's new dragon Toothless for his small size when he first saw him. He is not mentioned in any other book except the first one. In the books, Hookfang is one of Stoick's dragons, along with Newtbreath the Gronckle.
In the film
In the film, like the other main characters' dragons, he was kept prisoner at dragon training and the top of the class would've had the 'honor' of killing him. Hiccup was given the chance and instead, tries to connect to him and show the Vikings that dragons are not monsters, but after an outburst from Stoick, he becomes startled and begins to attack Hiccup in defense, until Toothless comes and protects his friend from the much bigger dragon, having no difficulty in subduing the enemy.
Later, when Hiccup is trying to get his friends to connect with the dragons and help fight the Red Death, Hookfang is the first one he brings out. Everyone is astounded by this, except for Astrid. Ironically, Snotlout is terrified enough to prepare a broken end of a spear as a weapon, in case Hookfang starts attacking, but Astrid nudges him to put it down. When Hiccup brings Hookfang closer to the others, he grabs Snotlout's arm so he can touch the dragon. Snotlout, obviously still frightened tries to resist, until Hiccup calms him and places his hand on his snout and he begins to growl in a purring manner. Snotlout's fear turns to amazement as he has made a connection, until Hiccup starts walking away to grab rope to "hang on" to the dragons, as the camera moves to reveal that the Gronkle, Deadly Nadder, and Zippleback are out of the cages, ready to be tamed.
During the final battle of the Red Death, Snotlout is seen riding Hookfang. When it is seen that Hiccup and Toothless have defeated the Red Death but Hiccup is no where to be found, everyone is upset. Toothless reveals that Hiccup is alive and everyone is overjoyed. Hookfang makes a brief appearance as he bows his head between two Vikings and is seen to make a "woo" sound with his eyes closed. The Vikings stare at the dragon in amazement.
At the end, Snotlout and Hookfang join the other dragons and trainers as they ride into the sky.
In Legend of the Boneknapper Dragon
In this short film, Hookfang makes a very short appearance. He's seen along with Snotlout, pouring water on Gobber's house, in an effort to put out the fire. Other than this, Hookfang did not make any further appearance.
In Gift of the Night Fury
In the short film Gift of the Night Fury, he becomes a father. He's even the one to fly Hiccup back home with the other dragons and their hatchlings. When they get home and land, Snotlout runs over and hugs his snout, as they are both ecstatic to see each other. At the Snoggletog party, Snotlout is seen playing with one of his children.
