The deity Killer of Rudra in red, with barred teeth and curled tongue, wearing skull crown, holding an offering vessel at heart level in his hand and brandishing a spear in his right hand, wearing colourful robes of silk embroidery, standing on a lotus base over a prostrate figure engulfed in a halo of fire, surrounded by lineage figures, Chakrasamvara, Panjarnatha Mahakala, Brahmarupa Mahkala and other protective deities 

Compare the style of a large 18th/19th century Tibetan thangka depicting Chaturbhuja Mahakala sold at Sotheby's New York, 1st April 2005, lot 84, (HAR No. 88588). Mahakala wearing robes and boots and with the same attributes of covered bowl and jewel-tipped club is depicted on a black ground painting in the Essen Collection now at Museum der Kulturen Basel, see Gerd-Wolfgang Essen and Tsering Tashi Thingo, Die Götter des Himalaya, München, 1989, p.208, cat. no. 127 (HAR no. 3314486). The inscription reads "mgon po dmar" which translates as "red protector".