The episode follows two parallel tensions that collide in the village of Berk:
For more episode details and cast information, you can visit the official DreamWorks Animation Wiki or IMDb . Riders of Berk episode 15: "Twinsanity" discussion thread
This episode marks the first appearance of Dagur, a recurring villain known for his instability and obsession with Night Furies.
Episode description: Dagur the Deranged visits Berk to renew a peace treaty between the Hooligan Tribe of Berk and the Berserkers, Reddit·r/httyd Twinsanity | Dreamworks Animation Wiki | Fandom