Umibōzu

Umibōzu (海坊主; Japanese pronunciation: [ɯ.mʲi.boꜜː.(d)zɯ, ɯꜜ.mʲi.boː-], lit.'sea priest') is a yōkai from Japanese folklore that has the form of a giant, black, human-like being.

Little is known of the origin of umibōzu but it is a mythical sea-spirit creature 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 ladle from the sailors and proceeds to drown them. The only safe way to escape an umibōzu is to give it a bottomless ladle and sail away while it is confused.

The monster is known by other near-synonymous names such Umihōshi (海法師) or Uminyūdō (海入道).