An ancient evil long thought forgotten. This creature first for is a writhing pile of purple limb and bone which searches for a host body that it can absorb and take its next form. Depending on what the host body is will determine its initial strength and form. Many believe copper is one of it’s weaknesses.
In New Friends, New Trouble adventurers tossed a wounded hound to the Polnorphus which then took the form of a purple demon dog which then quickly escaped to spread it’s disease across the land.