The Legend of the Boneknapper Dragon is a short 15-minute film that was released in a 2-DVD set with the How to Train Your Dragon DVD/Blu-Ray disc. It stars the original cast of How To Train Your Dragon and combines both CG and drawn animation.

Directed by: 
John Puglisi

Written by:
Aimee Marsh 
Johane Matte 
Ken Morrissey 
David Moses Pimentel 
Jeff Snow 
Peter Steinfeld

Produced by:
Bonnie Arnold 
Bruce Seifert

Music by:
John Powell

The film opens with a fire raging inside Gobber the Belch's house. Stoick orders a group of Nadders and Gronckles to help, dumping water over the house to put it out along with the other Vikings. The flames are extinguished and Gobber comes out of the house with his possessions, claiming to know what caused the fire. As Hiccup gets off Toothless' back, he asks Gobber what he's talking about, causing him to claim the Boneknapper Dragon hunted him down again, a beast that will stop at nothing to create the perfect coat of armor made entirely of bones. Stoick and the rest of the vikings refuse to believe his claims as Gobber decides to hunt down the beast once and for all with his pet sheep Phil in tow. Worried for his well-being, Hiccup persuades his friends to help Gobber search for the Boneknapper.

While traveling on their ship, a seven-man longboat, Gobber reveals his back-story of how the Boneknapper started to hunt him down. He revealed when he was a teenager on a summer vacation trip with his parents, he stopped inside an frozen cave for a bathroom break and was surprised to see a wall of ice with Vikings trapped inside. Gobber noticed one Viking held a treasure chest and decided to claim it for himself. It was here the Boneknapper appeared and chased after him. The Boneknapper flew after Gobber until he escaped with the treasure box.

In the present, the group crashes their boat on rocks and get stranded on a distant island with no way off. Gobber explains his second encounter with the dragon, when he was stranded on an island himself many years ago, armed with only his broom arm attachment. The Boneknapper found him again, causing Gobber to flee though an ocean filled with Hammerhead Sharks. His story becomes more wild when he claims a Hammerhead Whale attempted to eat the Boneknapper, but failed. The group, unsurprisingly, doesn't believe him, but Gobber is determined to prove the Boneknapper exists. He comes up with a plan to capture it once and for all, using Fishlegs as bait.

While they wait for the Boneknapper to try to attack a disguised Fishlegs, Gobber tells of his third encounter with the dragon. Still some years ago, Gobber found himself in a forest with only an egg beater arm attachment with the Boneknapper pursuing him relentlessly through the trees. Gobber claims to have climbed up and leapt over the crater of a volcano, where a Hammerhead Yak jumps out and saves him from the dragon. The Boneknapper still survived, prompting Gobber to lay out a series of traps to try to stop his predator. The BoneKnapper surfaced once again and chased him through the forest, avoiding everything he set up. The BoneKnapper chased Gobber all the way to a cliff, where he was saved by Thor himself tossing a thunderbolt into the ground and summoning the Hammerhead Yak riding the Hammerhead Whale.

Distracted by this story, nobody notices the Boneknapper finally showing its face, making a squeaky sound in its failed attempt to roar, causing the group to realize Gobber told the truth about the Boneknapper (if not about the yak, in any case). Gobber's trap fails and traps the group beneath a gigantic rib-cage of bones. As the Vikings take cover behind the ribs from the Boneknapper's fire, Hiccup realizes the treasure Gobber found, a belt buckle made of bone, is what the Boneknapper wants to obtain his roar, after noticing the small piece missing from his neck plate. Despite the group's initial objection of Gobber removing his pants, the old Viking is convinced (after being grabbed by the peg leg and shook about violently) and gives the bone back to the dragon, who finally gets his roar back. Having completed its objective, the Boneknapper becomes docile and thankful toward Gobber and the group rides it all the way back to Berk (with Phil on it's head), followed by other Boneknappers joining them in flight (as stated by Fishlegs, the Boneknapper's roar is its mating call). With that in mind, Gobber is certain Stoick and everyone else in Berk will believe him now.-