Episode Title:Alvin and the Outcasts.Episode Description:When the dragons are falsely accused of vandalism by Mildew and banished from Berk, the island becomes vulnerable for an attack from Alvin and the Outcasts, who land on Berk to seek out Hiccup (a.k.a. the "Dragon Conqueror" according to Alvin). Hiccup allows himself to be taken hostage by Alvin so he could go to Dragon Island, where he and his friends reunite with their dragons and defeat in a fierce battle. The dragons are then welcomed back to the island.