The Mahasiddha (Great Adept) Tsangnyön Heruka (The Crazy Heruka of Tsang, 1452-1507) was an eccentric tantric master of the Kagyu school of Tibetan Buddhism who left the monastery to become an itinerant yogi. He also composed biographies of early Kagyu teachers, including literary works on the life and songs of the renowned Tibetan Buddhist master and yogi, Milarepa (1040-1123; see M.72.108.1, M.81.90.2, and M.82.165.2).
Tsangnyön Heruka is represented as a scowling tantric yogi with his long hair (jata) tied up in an ascetic’s tall bun. Profusely adorned with bone ornaments, he also wears a jeweled cross-chest belt (channavira) symbolic of his spiritual power and a yogic band (yogapatta) over his right shoulder. He wears a tiger skin wrapped around his waist and underneath him as a rug. He holds a thunderbolt (vajra) in his right hand, and a skullcup (kapala) in his left hand. He sits in the relaxed posture (lalita asana) on a double lotus base.
See Himalayan Art Resources, no. 85763, https://www.himalayanart.org/items/85763