When Dagur appears at the Edge claiming to know where Viggo keeps his gold, the Dragon Riders fly off to find the stash and return Berk's stolen gold.
Tropes:
- But Now I Must Go: In the end, Heather and Dagur leave the riders to search for the missing Oswald the Agreeable.
- Chekhov's Skill: Dagur has Shattermaster do a reverse flying tackle with his heavy tail, smashing through a dragon-proof door. This proves vital in sinking the dragon-proof ships.
- Foregone Conclusion: Since she wasn't mentioned in the second film and Fishlegs will be competing for Ruffnut's affection, it was inevitable that Heather would leave the Dragon Riders.
- Hidden in Plain Sight: The gold Viggo stashed away on the island was disguised as pillars from an ancient Viking monument.
- Nice Job Fixing It, Villain: Viggo gives away the location of his gold by accident when he brings Hiccup in to gloat about his victory. The map on the wall behind him has an omission which Hiccup uses to deduce the location of the gold.
- Retcon: A possible explanation for why the episode acts like Heather didn't have an adoptive family that she had spent most of her life with and who had been killed by Dagur or Berserkers under his command.
- Running Gag: Dragon-proof chains to dragon-proof winches to...Fishlegs: Dragon-proof ships?!
- Wham Shot: When the dragon riders try to attack the fleet, they find instead of burning they just reveal a familiar green metal. Yes, the problems with the dragon-proof chains and dragon-proof winches have been resolved; Viggo now has ships made entirely out of dragon-proof metal.
