Here is a list of mythical creatures beginning with this letter and I am constantly gathering information from each continent and continually updating.
Ahkiyyini (Inuit)
The Ahkiyyini is a skeleton spirit in Inuit folklore. He is the ghost of Alaska, and causes tidal waves and earthquakes by moving his arms. Other articles state that when alive Ahkiyyini was always dancing and playing music. In death he would use his arm bone as a drum stick and his scapula as a drum.
He created music and danced a jig where it would make the ground shake to where boats would overturn. The skeletons of drowned men are typically dormant undead, risen to guard a treasure, so they often get coral and aquatic plants growing on them. When disturbed the Ahkiyyini will "awaken" and it will locate the source of the disturbance. In combat they will use tidal waves to attack and some ancient ones can rappidly create coral barriers.