Six-Armed Mahakala is distinguished from White Mahakala in that he is a dharma protector, not necessarily a wealth bringer. He, too, is a wrathful emanation of Avalokitesvara (Chenrezig). He is depicted as follows:
The Lord of Pristine Awareness has six hands and a body dark blue in colour. The first two hold a curved knife and skullcup, the middle two a human skull mala and trident, the lowest two a damaru drum and lasso. Adorned with a tiger skin, garland of heads, bones and snakes, and small bells on the hands and feet. Standing in a manner with the two legs together pressing down on Ganapati. With three eyes, bared fangs, eyebrows, beard and hair flowing upward with Akshobhya as a crown. Anointed with a sindhura drop on the forehead. Supported behind by a sandalwood tree, dwelling in the middle of a blazing mass of fire. On the [lower] left is Shri Devi, riding a mule, holding a stick and bag of disease. In front is yaksha Kshetrapala, reddish black, holding a curved knife and skullcup, riding a crazy black bear. At the right is Jinamitra, dark red, holding a hand drum and wheel. Behind [and above] is Takkiraja, black, holding a razor and blood filled skullcup. At the left is the lord of maras, Trakshe, holding a banner, and a skullcup to the heart, riding a black daemon horse with white hooves. He wears a long black silk cloak and boots. Outside of that sport the seventy-five great lords and an ocean of oath-bound ones together with retinue. (Jonang Taranatha, 1575-1634)
Sourced from Himalayan Art.