With Heather exposed as a double agent and the Flightmare in the custody of the Dragon Hunters, it's up to Hiccup to take Viggo on and try to out think him to save both.
Tropes:
- The Bad Guy Wins: Viggo outsmarts the Dragon Riders and succeeds in stealing the Dragon Eye. The only thing that doesn't go according to his plan is that Heather doesn't die, but that was because of Dagur, not the Riders.
- But Now I Must Go: Heather takes off without a word after the Flightmare has been driven off.
- Contrived Coincidence: Viggo's men attacked Dragon's Edge while the riders were away trying to steal the Dragon Eye, but were unable to since the twins were playing with it earlier and forgot to put it back.
- Convection, Schmonvection: When the front of Viggo's base is guarded by Typhoomerangs, Hiccup avoids playing into Viggo's hands by trying to attack from behind instead by exploiting the fact that Typhoomerangs breathe fire in vortexes and flies straight through the middle of the inferno unharmed.
- Criminal Mind Games: Hiccup tries to search Viggo's abandoned ship for any kind of clue and only finds a Maces and Talons board set up to represent Hiccup and Viggo fighting for Heather.Astrid: Why did he break Heather's piece?
Hiccup: Because the Traitor dies in the end. The Traitor always dies. - Human Chess: Viggo and Dagur are seen playing a game of "Maces and Talons" with their own men as pieces. The fact that Viggo wins by deliberately allowing nearly every piece he has to be captured causes Dagur to wonder where he fits in.
- Pet the Dog: After Ryker comments that siblings are supposed to always look out for each other, Dagur saves Heather from being executed and lets her go free, despite knowing that she is really his enemy and was plotting against him the whole time.
- Skyward Scream: Hiccup lets out a frustrated and defeated one when Viggo flies off with the Dragon Eye in his possession.
- Thicker Than Water: Viggo is so belittling and condescending towards Ryker, Dagur wonders why he doesn't ever just hit the guy. Ryker explains that siblings don't do things like that. This seems to inspire Dagur to look after his own sibling and set Heather free.
- Wham Episode: Viggo obtains the Dragon Eye, and unbeknownst to Hiccup, has used a bypass for the missing key to render it fully operational.Viggo: Hiccup will come to know that his carelessness will cause every dragon on earth to be slaughtered and sold, including his Night Fury.
- Wham Shot: The episode closes on a shot of the Dragon Eye's projection; a Night Fury being struck down and that Night Fury is in the center of all symbols that are Dragon Eye lens which means that they are somehow connected to Night Furies.
- Xanatos Speed Chess: While Hiccup tries his best to be as unconventional as he can, Viggo is still able to alter his strategies accordingly to come out on top.
