|“||After Heather and the Flightmare have been captured by Viggo and the Dragon Hunters, Hiccup must hatch a plan to outwit the dangerous new enemy.||”|
Hiccup and the Riders regroup back on Viggo's ship, Fishlegs reports to Hiccup that Viggo and the Dragon Hunters have escaped by almost vanishing when swallowed by a fog bank. Astrid is worried about Heather and the dragons, but Tuffnut says at least the Dragon Eye was not present, to which Hiccup's surprise he guessed correctly as he is still unaware Ruffnut stole it. Hiccup then realizes Dragon's Edge is unguarded so they quickly return to their island, to only find it ransacked by Viggo's men. Hiccup claims the Dragon Eye was stolen but is surprised to learn that the Ruffnut stole it, leaving it safe within the Riders. Hiccup thinks through Viggo's agenda, stunned by the way how he manipulated the Riders in one shot.
Meanwhile, Viggo is treating the captive Flightmare with adequate care, much to his older brother's chagrin. Viggo informs Ryker to plan a counter-attack before Hiccup can come up with one while also saying Heather will still prove useful for now at their disposal. Meanwhile, Dagur escorts his sister to her cage, but Heather tries to convince Dagur to unite with her and take orders from no one as part of their Berserker culture but to no avail.
Hiccup and Astrid travel back to Viggo's abandoned ship and try to find any leads on Viggo, but as they search they find the ship completely deprived of everything. While searching, Hiccup informs Astrid that Viggo fights with intellect by putting himself far from harm's way, and deals with different scenarios of a situation all at once. Toothless then finds a covered object, when Hiccup removes the covering he finds a board game known as Maces and Talons, he identifies the characters within the game, serving as a coordination on how Viggo executed his master plan to capture Heather and lure the Riders. Hiccup sees that Viggo is asking him to 'play' with him, but he finds a piece broken in two to which he identifies as the 'traitor' being Heather, meaning eventually Heather will be executed in the 'end of the game'.
When Hiccup brings the decision-making board game, Fishlegs exclaims it serves as a challenge for Hiccup being future chief as it is designed for planning out battles, but Hiccup denies that claim as he says Viggo is making him 'play' to outsmart each other, because if he doesn't Heather will die. That night, Hiccup executes his plan to hopefully outsmart Viggo's wit, they fly overhead in cloud cover to be undetected by the Dragon Hunters, but their cover is blown as Snotlout makes Hookfang fire his body up. The Dragon Hunters retaliate by 4 captive Typhoomerangs bursting huge walls of tornado-like flames. The Riders suggest to fall back and find another route to attack through Viggo's island, but Hiccup sees this as a distraction for them to fall in a trap, and the only option is to go through the flames. The fact that the flames emerge in a Typhoon like direction, Hiccup theorizes going through it will leave them untouched by the flames, the Riders hesitate but proceed anyway.
The fires consume the Riders, the guards are left curious to their disappearance and orders the Typhoomerangs to stop, giving the opportunity of the Riders to attack the guards, free the Typhoomerangs, and break through Viggo's lines. News about Hiccup breaking through reaches Viggo's camp, impresses Viggo as the first phase of his plan fails. Ryker suggests for action, with the plan to force Hiccup to go through the back of the island fails, most of Viggo's men are left with no action as they are expecting the Riders to appear at the other end of the island. However, Viggo reassures Ryker everything is still going according to plan, much to Ryker's frustration. Dagur reports to Viggo that he has done what he is told about what to do with Heather, and when Dagur tries to suggests something to Viggo, he immediately tells him to stop and just follow what he is told. This indication completely irritates Dagur and silently asks Ryker has he ever thought of trying to beat him for enjoyment as he is after all, the big brother, Ryker answers he always has but he can't as he emphasizes to Dagur that they are brothers.
In the meanwhile, Hiccup presumes he has found the cage of Heather but ends up falling into a trap instead as it is actually Viggo who is inside the cage. Surrounded by Dragon Hunters, Viggo demands that Hiccup surrenders the Dragon Eye to him so that he and his friends can be spared. Hiccup refuses and as soon as Hiccup mounts up to Toothless, Viggo gives the signal to one of the Dragon Hunters to activate a mechanism on the Flightmare's muzzle that forces him to spray the paralyzing mist at Hiccup and Toothless. With Hiccup and Toothless frozen, Viggo easily grabs the Dragon Eye and he and his men flee.
Dagur and two other Dragon Hunters relocates Heather to her new cell, when Dagur points to what direction the guards begin to suspect something is wrong, to which Dagur knocks them unconscious. Dagur tells them that he has now broken alliance with Viggo, Dagur breaks Heather's handcuffs and reunites her with Windshear. As Dagur leaves, he gives one last look at Heather.
Moments later, Hiccup and Toothless regain their movement and they follow Viggo's trail. At a cave, Ryker is wondering why they haven't killed the Flightmare, Viggo does not answer and he uses the Flightmare's glowing mist to do something mysterious with the Dragon Eye at it begins to light up strangely. However, Hiccup and Toothless is on the pursuit and closes in, at the last moment, Viggo finishes his business with the Flightmare and lets it loose, driving Hiccup and Toothless away from them. When emerging from the tunnels, Hiccup and the Riders try to scare off the Flightmare. Struggling, Heather and Windshear appear and help Astrid and Hiccup finally scare off the Flightmare for good before they fly off by themselves to the unknown.
Hiccup and Toothless orders to go back to the tunnels and track down Viggo, however, Astrid points out that it is no doubt that Viggo and his men had already fled. Realizing that he lost again, Hiccup screams in great fury as a worried Toothless watches. While the rest of the group recovers from the Flightmare's attacks, Astrid checks in on Hiccup and tries to reassure Hiccup that the Dragon Eye is useless without the Snow Wraith tooth as its key.
Meanwhile on the Dragon Hunters' ship, Ryker is relieved that the Dragon Eye is within their grasps but considers it useless. Viggo proves him wrong by slamming his fist on the table, causing a frightened and caged Terrible Terror to light up the Dragon Eye much to his older brother's shock. Viggo explains that when the Dragon Eye was constructed, the locking mechanism was given an emergency release; a filament that can only be burned away by the glow of a Flightmare.
Viggo points out that with Hiccup unaware he has unlocked the Dragon Eye, he now has the weapon at his disposal to find every single species of dragon on earth to either be slaughtered or sold by the Dragon Hunters, including Toothless. The episode ends with the camera panning over to the drawing of a Night Fury at the very center of mysterious drawings and scriptures.
- At the end of the episode, when a Terrible Terror lights the Dragon Eye, it is clearly seen that a Night Fury is in the center of all symbols. This could mean that every Dragon Eye lens can be found or is in someway connected to Night Furies.
- This episode is named after the fictional Viking board game called Maces and Talons.
- This is the first time Hiccup has been called Hiccup Haddock the III, nearly identical to his full name. The "Horrendous" part is still left out.
- Dagur broke his alliance with Viggo.
- Heather flew to an unknown location.
- The machine Hiccup uses to launch himself is the same one Dagur used in "The Flight Stuff".
- Not counting Heather, Astrid and Fishlegs were the only Dragon Riders who were not paralyzed by the Flightmare. However, they were they only ones who were paralyzed in "Fright of Passage".
- When Tuffnut asks "Viggo's here?" it is similar to what he said in "The Flight Stuff" about Dagur. ("Dagur's here?")
- Hiccup screaming at the end is similar to his yell in How to Train Your Dragon 2. Toothless' reaction is almost the same as well. This is the first time chronologically that we see Hiccup this frustrated.
- Macey is mentioned.
- Jay Baruchel as Hiccup Horrendous Haddock III
- America Ferrera as Astrid Hofferson
- Christopher Mintz-Plasse as Fishlegs Ingerman
- Andree Vermeulen as Ruffnut Thorston
- T.J. Miller as Tuffnut Thorston
- Zack Pearlman as Snotlout Jorgenson
- Mae Whitman as Heather
- David Faustino as Dagur the Deranged
- JB Blanc as Ryker Grimborn
- Alfred Molina as Viggo Grimborn