This type of mask is used during bhuta worship, practiced in the coastal region of Karnataka. Bhutas are celestial or ancestral spirits that are represented by hundreds of different forms, including forms of Shiva, buffalos and boars, as in the present example. During an all-night festival, the mask is worn by a trained medium who invites the bhuta to possess him. He then sings, dances, tells stories, gives advice and solves problems for the sponsoring family or village group. See S. Aryan, Unknown Masterpieces of Indian Folk and Trival Art, 2005, p. 61-63, for bhuta masks made in brass; and the recent exhibition Dancing Masks - Bronzes from Southern India, 17 May - 23 August, 2009 at the Rietberg, Zurich.