Mester Stoor Worm

The Stoor worm, or Mester Stoor Worm, is a sea serpent from Scottish folklore. Stories of the creature originated in the Orkney islands, although it may be based on Jörmungand the Midgard Serpent from Scandinavian mythology. It also bears a resemblance to the dragon from the story of Saint George.

Assipattle and the Stoor Worm
The ancient kingdom of Leegarth was thrown into turmoil by the arrival of an evil sea serpent that contaminated plants and killed humans and animals with its poison breath. The king was advised to sacrifice seven virgins to the monster to make it leave. Eventually the king was told to sacrifice his daughter to the creature by a wise man, and offered a magic sword and his daughter's hand in marriage to any hero who could slay the beast. A farm boy named Assipattle offered to slay the monster, stealing a boat and some hot peat and rowing out to sea at dawn, when the stoor worm was waking up. As it yawned, Assipattle sailed in the creature's mouth and threw the still-burning peat into its stomach. The pain gave it a fit of retching, throwing Assipattle out of the monster's mouth. As it writhed in pain, its teeth fell out and formed Orkney, Shetland and the Faroes. Its tongue fell out and formed the Baltic Sea and the dead body of the creature formed Iceland.