Dagur is always up to no good! He traps Dragons and steals their Eggs in hopes of training them for his army. Sneaking on his ship, and past this traps, is the only way to save them.
In "A View to a Skrill, Part 2", Dagur is in his ship when he goes head to head against one of the Outcast ships that carried Alvin as they fight over the Skrill.
Dagur's Ship appears in the Expansion "Wrath of Stormheart". It appears as a basic Berserker vessel. It is captured on the much larger The Tempest. The ship is loosed, but gets crushed in the larger ship's spiked pincers.