In the series, the peaceful coexistence between dragons and vikings, which were former foes, have not been so peaceful as they'd think. Hiccup, after fiddling around with the eye, finds that it's activated by the fire of any Dragon and works as a light projector showing him maps, writing and Dragons he's never seen. They enforce their royalty rights immediately getting the other riders doing meaningless and annoying tasks. When they return, the riders re-welcome Heather while offering their support and she and Astrid take the time to bond. After making a plan, they release the captive Singetails only to find the dragons turning on them and forcing the riders to fall back in a cave with no escape.
The riders, Heather in particular, refuse to listen and head in anyway, leaving Dagur to take charge and sacrifice himself to allow the riders to escape. They investigate only to be imprisoned by a dragon-worshiping tribe called the Defenders of the Wing led by Queen Mala, who believes them to be hunters for their subjugation of dragons. The Screaming Death happened to be digging shafts underneath the islands that were large enough to cause the islands to collapse into the sea, forcing dragons to abandon their homes. The riders are left only with the resolve to reclaim the Dragon Eye before he can use it. Sullivan Jack Thomas February 16, 2018 2018-02-16 After a battle with the Flyers, the Riders discover remnants of Deathsong amber underneath a Singetail's wing, leading them to deduce that Krogan is using a Deathsong to lure and capture Singetails for his Flyers.
After arriving, he immediately finds one and tries to train but discovers it is very aggressive and has the unusual ability to mimic the fire blasts of other dragons, such as a Gronkle's lava blast and Nadder's magnesium fire breath. Astrid is cured and the riders offer words for the deceased sailors. Only Hiccup and Snotlout manage to escape while the others are captured. Dagur leads Viggo's fleet away and swears to Heather that he will return to answer her questions, leaving his worried sister behind. In the end it was revealed that Stoick missed Thornado but in turn comes to bond with the Rumblehorn, who becomes his new dragon Skullcrusher. Though they receive reprimand, Astrid promotes them to full Riders with Gustav as the leader and remains on Dragon's Edge.
Before leaving, Alvin arrives with reinforcements to help keep Berk safe while Stoick is recovering. Hiccup and Toothless manage to lure the Skrill into a glacier, freezing it once again. Using Mala's advice to look at things differently, Hiccup learns to use the Sentinel's behavior and abilities to his advantage and with help from the Eruptodon, manage to escape, and Hiccup destroys Tuffnut's guide to ensure that no other human will discover Vanaheim. Krogan and his Flyers arrive to take and lens and succeed after the Riders choose to instead evacuate the injured Armorwing rather than pursue Krogan. Dagur captures him and Fanghook, whereby Gustav appears to become a part of their crew claiming he knows how to get Dagur the Dragon Eye. Meanwhile, Hiccup and Snotlout travel to Wingmaiden Island to escort Atali to the meeting, where Atali leaves her second-in-command, Minden, in charge of the island, though Minden is upset at not being allowed to attend the meeting as well. Fortunately, a magical messenger gives her a priceless Christmastime gift: She is instantly transported three years into the future, so she can see what her life will become.
Back on Vanaheim, Fishlegs looks through Oswald's hut for any information on the Sentinels and discovers they are not dead, but merely in a state of hibernation. Astrid, after seeing her home destroyed, decides to train a new team of Dragon Riders. While looking it over, the riders believe Viggo is keeping them from something on a nearby island. The dragons, being the wild beasts they yet remain, unintentionally stir up trouble time and again, leading to the more grouchy types among the Vikings to take exception to their presence. Meanwhile, Stoick and Gobber, left in charge while the riders are away, lose Tuffnut's pet chicken and each try to replace it with a new one. Ruffnut tries everything from having Snotlout bitten by other dragons and reasoning with him as he is about to fall off a cliff, and Hiccup and Fishlegs reveal the Lycanwing legend was invented to protect a pair of Dragon Eye lenses hidden on another island, but Tuffnut is only convinced when Snotlout appears and states he was actually bitten by a wolf, which bites him as well. The search for Oswald doesn't end on a happy a note, with Dagur only finding his remains and a last message to him and Heather, though he continues his father's work by helping the Sentinels defend Vanaheim from the rogue Grim Gnasher dragons, and leaves satisfied that his father passed proud.
Hiccup elects to nurse it back to health but Snotlout opts to leave it on account of its paralyzing abilities. The young Stinger is torn between its pack and the riders, but Hiccup convinces it to go back with its family. The Scauldron rebuffs their attempts for help, so no one but Ruffnut seems to calm it down. That evening, the riders receive a letter from Dagur who says he is looking for Heather, and the riders promise to keep her location secret until she is ready. Jones Jack Thomas June 24, 2016 2016-06-24 With Dagur's information and a map of the location stolen by Johann, the riders send Snotlout and Gobber undercover with Berk's reluctantly lent gold to the hunters' latest dragon auction to rescue the dragons and cripple Viggo's business.
Back on the Edge, Astrid works to set up defenses with the twins and explodes into a heated argument with Ruffnut who says that she does not respect others. The other riders interrogate the hunters for information on their whereabouts and trick them into sending word to the arena and following the Terror to their location. Unknown to them, a new species of dragon living on the Island, known as the 'Night Terrors', lives there too, and they ambush and scare Tuffnut. Hiccup is captured by everyone from two dim-witted brothers to Savage to the masked man from Viggo's auction, leading the riders and Stoick on a wild goose chase to find him. Hiccup tries to tame the imprisoned dragons while Toothless battles in the arena, soon pitted against the resident champion, the Triple Stryke. Just as they leave, however, the volcano erupts. In the task you have to cross the island of dragons from one end to the other, at night, with no dragons, and 1 weapon.
Though still doubtful, Hiccup and the others scramble to keep the siblings from noticing each other by sending Heather away while offering Dagur a Gronckle he names Shattermaster to get him to leave, but they cross paths anyway. During the trip, they are ambushed by hunters, but the twins rescue Hiccup and Johann and deduce that the only way the hunters knew they'd be there is if there was a mole within their group. When it is about to escape into the sea, it ends up cornered by the Scauldrons, but is saved by the rest of its pod. De Marco February 12, 2014 2014-02-12 1. He manages to pass two life-threatening trials but fails in the third, though Mala commends his effort and makes him a guest of honor in a celebratory feast. Miller, Brook Chalmers, David Faustino, Mark Hamill, Paul Rugg 7.