Dragon's Edge is under siege by the Dragon Hunters. With Hiccup, Snotlout, and Fishlegs away, and Ruffnut captured, it's up to Tuffnut and Astrid to defend the edge until help arrives.
Tropes:
- Androcles' Lion: Fishlegs gains the wild dragon flock's trust by helping a juvenile Gronckle cough up a stone it was choking on.
- Aw, Look! They Really Do Love Each Other: When Astrid accuses Tuffnut of not taking the situation seriously, Tuffnut points out that he is being serious in his own way, as he would go to any length to save his sister.
- Backup Bluff: Tuffnut's plan to defend Dragon's Edge is to use dummies to make it seem like there are more people defending the Edge than there actually is.
- Big Damn Heroes: Hiccup arriving on the scene on the sunrise with a cavalry of allied dragons.Dagur: Why does he always have to make a big production of everything? I really hate that guy.
- Call-Forward:
- Hiccup uses his flight suit not just to save himself when separated from Toothless, but also as an aid to help tame dragons by demonstrating similarity to them, along with the way he uses his fire sword in How to Train Your Dragon 2.
- Astrid imitating Hiccup also calls forward to the second film.
- Curb-Stomp Battle: Astrid vs. Dagur. Dagur challenges her to a fight by physically tackling her off Stormfly, but after she kicks him off her, she charges at him and pins him against the wall in less than three seconds.
- Genius Ditz: Best exemplified for Tuffnut here, as his ideas and inventions are more effective against the hunters than Astrid's traps.
- Oblivious to Hints: Heather tries to rescue Ruffnut by making it easy for her to free herself, but she doesn't take the hint.
- Remembered Too Late: It takes Dagur a second to recognize the smell of Zippleback gas in the air, and by the time he does, his men have already lit some flaming arrows. Cue explosion.
- A Riddle Wrapped in a Mystery Inside an Enigma: Tuffnut says a variation of this phrase, talking about Heather.Ruffnut: I cannot figure that girl out.
Tuffnut: One might even say she's an enigma, wrapped in a riddle, wrapped in yak bacon. - Scar Survey: Fishlegs sees scars on the wild dragons and realizes they came from dragon hunters, explaining this group's unusual aggression.
- Spotting the Thread: On returning to Ryker after the Zippleback gas incident mentioned above, Dagur corrects Ryker's assumption that it was Toothless who attacked him, at which point he realizes that they'd only seen Stormfly and Barf And Belch, revealing to the hunters that it was only Astrid and Tuffnut there.
- Talk to the Fist: When Dagur remarks that he hates Hiccup's dramatic entrances, Astrid (with whom he'd been fighting, and who had him pinned) just responds by knocking him out.
- Thicker Than Water: Ryker isn't pleased when Dagur talks about executing his cousin Lars number two when the latter deserts their army.
- Too Dumb to Live: Subverted when Heather lets Ruffnut escape on Windshear; Ruffnut visibly goes in a completely different direction than towards Dragon's Edge, but she's actually heading off to get backup in the form of Hiccup.
