"Reign of Fireworms" is the (part of the Race to the Edge series) in the How to Train Your Dragon franchise. In this episode, the Dragon Riders discover that Dragon's Edge is directly in the path of a massive Fireworm migration, threatening to burn their base to the ground. Episode Summary [S3E7] Reign Of Fireworms

For more details on the dialogue, you can read the full episode transcript on the How to Train Your Dragon Wiki . The climax involves the Riders managing the migration

The Twins find a rock that leads to a dispute over who actually "owns" Dragon's Edge. Episode Summary For more details on the dialogue,

The Riders work to fireproof the Edge by securing water supplies and relocating vulnerable dragons like the Night Terrors to desolate caves.