Umibōzu (sea priest) is a paranormal phenomenon or yōkai from Japanese folklore. Little is known of the origin of umibōzu but it is a sea spirit and as such has multiple sightings throughout Japan. Normally, umibōzu appears to sailors on calm seas which quickly turn tumultuous. It either breaks the ship on emergence or demands a bucket or barrel from the sailors and proceeds to drown them. The only safe way to escape an umibōzu is to give it a bottomless barrel and sail away while it is confused.
