The Piasa

Serpent underbelly, eagle talons, antlered skull, human eyes. The Piasa of the upper Mississippi was once the terror of the native peoples, its black shape blotting out the sun as it soared above battlefields like a bloated vulture. It took children from the forests and women from the fields, and no hunter could stand against it and live.
Then it was gone. None could say where, or when, or even how. Slowly, the people grew less cautious, less afraid. But they carved a warning into the limestone above the turbulent waters. A dragon-thing, with the face of a man. Just in case.