"So indeed is a barghest"
A ghostly Black Dog.
Public DomainA ghostly Black Dog. - Credit: Spettro84

The barghest is a terrifying black dog of English folklore. It is said to have large teeth and claws, glowing eyes and is often associated with the devilĀ and death.

Other such dogs are Cerberus, guardian of Hades, and the Black Shuck.