Shell Shocked, Part 2 is the thirteenth and final episode of Dragons: Race to the Edge, Season 4. It was released on Netflix on February 17, 2017. It is the continuation of Shell Shocked, Part 1, and the finale of the season.
The Dragon Riders debate over what to do with VIggo. Astrid and Fishlegs don't trust him one bit, but Ruff and Tuff say he'd "be fun to hang out with." They decided to lock him up in the stables. In the previous episode, Viggo warned that Ryker and the Dragon Hunters would be coming soon and he needed them. Ruff and and Tuff report a fleet of ships heading their way, lead by Ryker.
Hiccup rounds up the rest of the Riders along with Heather and Dagur, and they decide to make a stand at the Edge to stop the Dragon Hunters from advancing onto Berk. Everyone leaves then, except for Astrid and Hiccup, and when Tuff notices, Heather says they need to talk alone, hinting she knew about their relationship.
Ryker is then shown with his large dragon ship, and everyone goes to their huts to hide. Everyone waits the attack out, except for Fishlegs, who is protecting the baby Eruptadon near the volcano. After, it is shown Snotlout let Viggo out, saying he was scared of him. The dragons and their riders attacks, with the Shellfire shooting back at them due to torturous hammering from Ryker's soldiers. Viggo, meanwhile, begs for Snotlout to let him out as the building sets on fire. They attack continues, until Hiccup decides to regroup, seeing Snotlout coming. Hiccup scolds him for keeping Viggo in a burning building, and Hiccup leaves to save the older man.
Fishlegs, Dagur, and the Triple Stryke are also fighting Hunters, when Shattermaster gets hit. He and Dagur lie by a rock and wait. As they get closer, Dagur and Shattermaster ambush them with the help of Sleuther.
Hiccup then rescues Viggo, saying "If (I) left you here to die, it would make me no better than you." Viggo asks to help again, and Hiccup now accepts, while they seemingly head off alone after consulting the other Riders. Later, Viggo gets inside Hiccup's head and teases him about being in love with Astrid and how he handles it along with war. Hiccup who is evidently feeling embarrased then tells him to stay out of his personal life. As they continue to look for the Shellfire, Viggo pulls out a knife as if he's about to harm Hiccup, but Astrid arrives just in time and orders him to drop it, which Viggo does, but reveals the action was to lure the Submaripper to the fight rather than to kill Hiccup. During the battle, Hiccup leaves Viggo on an island due to him slowing them down, and Viggo smiles maliciously as he watches Hiccup fly off. The Submaripper destroys Ryker's fleet with it's whirlpool, presumably killing Ryker and ending the battle. When Hiccup thinks it's all over, Viggo appears on Stormfly with Astrid as his hostage at a volcanic crater. He asks an enraged Hiccup for the Dragon Eye in exchange for Astrid's safety, and if he's willing to "sacrifice his future" for the Dragon Eye. Hiccup angrily answers that he isn't and throws the Dragon Eye over Viggo's head, giving Astrid a chance to escape. The Dragon Eye falls into the volcano and is destroyed. A tremor then causes the ground beneath Viggo to give way and he falls into the volcano to his death. Finally, after it's all over, Astrid apologizes to Hiccup about not listening, they promise to keep their relationship professional when in combat, and to be honest with each other. As they share a kiss, the rest of the gang arrive then run up and hug them, finally understanding why Hiccup and Astrid have been acting strangely since they first started courting. As they fly around the island to survey the damage, the volcano suddenly erupts.
- Jay Baruchel as Hiccup Horrendous Haddock III
- America Ferrera as Astrid Hofferson
- Christopher Mintz-Plasse as Fishlegs Ingerman
- Zack Pearlman as Snotlout Jorgenson
- Andree Vermeulen as Ruffnut Thorston
- T.J. Miller as Tuffnut Thorston
- Mae Whitman as Heather
- David Faustino as Dagur the Deranged
- Barf and Belch
- New Protector
- Viggo's men control the Shellfire by striking on the chains that attach their ship to its body. This is similar to how Drago Bludvist commands his Bewilderbeast.
- Viggo mentions a life sized, solid gold Maces and Talons game, the likes of which may have been a part of Hamish II's treasure as we saw in the episode Portrait of Hiccup as a Buff Young Man.
- Hiccup and Astrid kiss at the end with all the teens watching for the first time.
- The line "This changes everything!" is repeated but this time by the riders and not Hiccup.
- Snotlout states that he can help Hiccup with his 'gambling' problem, but that it will take "like 10-12 steps" referencing 12 Step programs for substance abuse.
- The Submaripper and Shellfire are revealed to be natural enemies, and their fight may be a reference to the Bewilderbeast battle in the second film.
- This episode ends on a cliffhanger, with the volcano exploding over the Edge, and Viggo, Ryker, and the Dragon Eye missing.