Ukoy

The Ukoy are from Filipino mythology. They have human upper bodies with arms and legs replaced by eight to fifty octopus tentacles. They are incredibly strong and can swim as fast as a dolphin. They will kill any humans that approach their underwater cave homes, though they are not actively hostile. They are strong underwater but weak on land.

Citations:

Maberry, Jonathan. Vampire Universe: The Dark World of Supernatural Beings That Haunt Us, Hunt Us, and Hunger for Us. United States, Kensington Publishing Corporation, 2006.