The Winterwurm

Few venture to the frosty northern waters of the Episay Ocean, and, as if freezing cold temperatures weren't enough, those who do might have to contend with the Winterwurm.
An eighty foot beast that lives under the surface of the sea, it has twenty-seven fins each the size of a frigate mainsail that propel it through the waters at thirty knots. There is no escaping the Winterwurm once it has caught the scent of fresh caulking in the water. The worm-like creature has teeth as sharp as swords and claws like spears, its eyes burn with an intensity that makes the water bubble.
It attacks by racing vertically from the dark depths of the ocean and smashing into the hull of a ship, its body hurtles out of the water and wraps around the ship to crush the timbers as if they were twigs. Once the ship is in splinters the Winterwurm will retreat, leaving the survivors to cling desperately to the driftwood. The Winterwurm stalks the wreckage for days, letting the survivors ferment and bloat in the cold, salty water. When it smells a morsel is ready for eating it will bring its serpentine body to the surface and circle the wreckage, shepherding its prey together. Then it submerges and waits. For a moment, the survivors might believe their prayers are answered. Until the worm strikes, plucking at the victim from amongst the others, dragging them to the depths to feast on the gurgling meal.
While the other survivors are left fearing for their own turn.

Spread

The myth has spread from the Thyorn lands down to Dividend

Variations & Mutation

In Candador there is a similar myth of the sumsurpia, a serpentine monster that hunts the southern waters.

In Art

There is a clan of Thyorn called the Vurmar, who have a depiction of the Winterwurm as their emblem on the rorswood shields.