Black demons

Black Demons are lesser Maiar who have allied themselves with Morgoth. Their forms vary infinitely, as do their abilities. They can sometimes be persuaded to aid Men or Elves in evil deeds (oreven in good ones, if heavily constrained by a Good power of great might), but unless the evil-doer requesting this service has protected himself or herself carefully and laid the strongest constraints on the Demon, little good will come of such bargains in the end. Demons often partake of some of the characteristics of natural forces: Balrogs as Spirits of Fire are a very good example. This is, no doubt, because of Eru's original plans for these spirits as directors and guardians of these natural forces.