WMG / Clash of the Titans (1981)

Calibos is supposed to be the imperfectly remembered inspiration for Satan

Calibos in this movie has no counterpart in Classical Mythology. However, he very much resembles the popular Christian conception of the Devil, being an evil (well, mostly evil) tailed and Horned Humanoid armed with a trident (in Calibos' case, used as a prosthetic for his cut-off hand), who was originally of fairer form before being cursed.