Darkhounds are Shadowspawn in the form of large black dogs, the size of ponies. They are said to run with the Wild Hunt. They do not leave footprints in any material except stone. It is said to be particularly dangerous to meet them at crossroads, or at twilight. (Cf. Crossroads of Twilight (novel).) Crossing running water is supposed to be the only way to evade them short of killing them. They are usually found in packs of ten to twelve.

After being slain, they dissolve into shadow and reform their body, though they can be slain by balefire. Their blood and saliva is extremely poisonous. Even small quantities can kill, albeit slowly, and larger quantities can kill too quickly to be Healed. Their claws are sharp enough to dig through bronze.