Ghastly decapitated horse heads that can be found in the first level of Konami's 1991 Super Castlevania IV [original Japanese title: Akumajo Dracula (Demon Castle Dracula)] Super Nintendo Entertainment System (SNES) video game. From a distance, they appear to be grisly inanimate remains, but, should anyone be foolish enough to get too close, these equine creatures will suddenly return to life, floating up into the air and immediately giving chase to the would-be trespasser in a ghostly fashion. Should he catch up with his prey, which he invariably does, Mr. Hed will inflict painful bites with his teeth. Fortunately, these rotting horrors are structurally unsound and can be easily returned to lifelessness with a single strike from Simon Belmont's whip.
The monster's name is obviously a humorous take on the titular talking horse featured in the classic Mr. Ed television sitcom.
For comparison/informational purposes, below are some relevant images:
« Return To My Konami Video Game Fan Art Gallery