Three years after the war with Dagur and the Berserkers, Hiccup finds all the dragons discovered in the Archipelago, and his friends happily settled in the village of Berk.
Meanwhile, Dagur the Deranged has broken out of Outcast Prison, and his first target on the revenge list is Hiccup. He plans to build a new army, and perhaps hunt down new dragons.
Tropes:
- Beard of Sorrow: Dagur grew a patchy one while in prison.
- Big "NO!": Hiccup when he realizes Dagur was really aiming the rock at the Reaper's bow to capsize it.
- The Bus Came Back:
- Somehow Dagur found Savage, his old Yes-Man, and brought him back.
- Dagur also found Trader Johann's ship and tossed him aboard.
- Call-Forward: Hiccup falls off Toothless during a stunt and remarks he should think of some way of dealing with that, alluding to the flight suit he has in How to Train Your Dragon 2 and later in the series.
- Cat Scare: Done with a bird in one of the cages, it scares both Hiccup and Toothless.
- Chaotic Good: An In-Universe example, by serving "Loki," the god of mischief, the twins are this, pulling many pranks on Berk.
- Curb-Stomp Battle: Dagur versus the Outcast guards. He wipes the floor with them in less than five minutes and makes his way to a ship to escape.
- Desperately Looking for a Purpose in Life: Now that most of the dragons in the Archipelago have been found, Hiccup is a bit lost, especially when Astrid says she no longer wants to join him on searches for new dragons.
- Disability Immunity: The first trap Hiccup triggers on The Reaper is a Bear Trap that closes on his leg. Thankfully, it's his prosthetic pegleg that got caught.
- Dumbass Has a Point: Hiccup likes the twins' plan to steal from the ships in the graveyard before Dagur can. The problem then lies in everyone distracted when Dagur arrives.
- Exactly What I Aimed At: Dagur launches a rock at Hiccup and Toothless, who dodge it easily. They then realize that it landed right in the Reaper, where the other dragon riders are caged, and causes the boat to start sinking.
- Freeze-Frame Bonus: One of the mounted dragon skulls in the Reaper's captain's quarters is a Boneknapper.
- The Guards Must Be Crazy: Ho boy, where to start. First, the Outcast idiot that gave Dagur a key in exchange for an unknown reward, and the other Outcasts go down easily in a Curb-Stomp Battle because they're joking about an unknown conversation.
- Hostage for MacGuffin: Hiccup ends up trading away the unknown treasure for his friends' lives when Dagur captures them.
- Idiot Ball:
- One Outcast guard had the bright idea to help Dagur escape, for an unknown reason.
- Hiccup going into the booby-trapped ship with Toothless before Dagur comes, risking his life to satiate his curiosity.
- Jaw Drop: Tuffnut and Snotlout gives this when Johann went right to the point with no long stories.
- MacGuffin: The "treasure" on the Reaper that Dagur wants to get his hands on resembles a telescope.
- Names to Run Away from Really Fast: A ship called The Reaper.
- Noodle Incident: Dagur remembers Hiccup dancing at peace treaties between the Berserkers and the Berkians.
- Offscreen Moment of Awesome: Dagur and his armada of three men somehow managed to get the jump on all the Viking teens except Hiccup, and lock them in a cage. Note that Astrid and Snotlout are skilled at hand-to-hand combat, the twins have thresholds for pain somewhere in the "nonexistent" range, and Fishlegs is the size of a baby killer whale.
- One-Man Army: Dagur. He needs an armada to get his revenge on Hiccup, but he broke out of prison without breaking a sweat.
- Prisons Are Gymnasiums: Dagur, while he's trapped in a typical Outcast cell for three years, was able to stop his muscles from atrophying.
- Put Their Heads Together: Dagur gets rid of two guards by knocking their heads together from behind.
- Rewarded as a Traitor Deserves: The guard that slipped Dagur the key to his cell gets knocked out as a reward. Dagur puts it best:Guard: No, Dagur, don't! I helped you, remember? I left the key to your cell!
Dagur: Which makes you a traitor. (knocks him out) I hate traitors. - Sadistic Choice: When Hiccup goes after Dagur after the Hostage For Macguffin scene, Dagur proceeds to shoot a rock into the ship where Astrid, Fishlegs, Snotlout and the twins are still trapped. As Dagur points out, Hiccup can either try and fight him for the treasure or rescue his friends. Hiccup chooses his friends, no questions asked.
- Taught by Experience: Dagur seems to have learned from Alvin, exploiting Hiccup's predictable impulsiveness at the end of the first episode. He invokes a Sadistic Choice that gives him a head start against the Berkians.
- Took a Level in Badass: Dagur. Prison has not improved his temperament, but he's become a One-Man Army who can assemble an army with funds stolen from Trader Johann and he manages to outsmart Hiccup at the end of the episode.
