Songs and stories have been passed on for generations, telling of a person. A person so cruel, that he can best be described as a beast. The songs tell of him only ever showing up during twilight, hence the name, Twilight Beast. Whenever he shows, he leaves no one alive. The only reason this tale exists is because he let someone escape. After all, dead men tell no tales.
One of the more recent rumors, and a possible sighting of the beast, is in Skull Bay.
NOTE FROM DM If ever you manage to encounter this beast, you can assume you're going the wrong way ;)