Hayagriva is a wrathful manifestation of Avalokiteshvara. There are believed to be 108 forms of Hayagriva. His special ability is to cure diseases, especially skin diseases even as serious as leprosy, which is said to be caused by the Nāgas (water spirits with serpent bodies).
In his simplest form Hayagriva is depicted with one face, two arms and two legs. Everything about him is wrathful - a scowling face with three glaring eyes, a roaring mouth with protruding fangs, a pose of warrior’s aggressiveness, a broad belly bulging with inner energy, a sword raised threateningly in his right hand, his left hand raised in a threatening gesture and snake ornaments. This terrifying aspect expresses compassion’s fierce determination to help us overcome inner egotism and outer obstructions.