Tsangnyön Heruka (Tibetan: གཙང་སྨྱོན་ཧེ་རུ་ཀ་, Wylie: gtsang smyon He ru ka "The Madman Heruka from Tsang", 1452-1507), was an author and a master of the Kagyu school of Tibetan Buddhism. Born in Tsang, he is best known as a biographer and compiler of the Life of Milarepa and The Collections of Songs of Milarepa, both classics of Tibetan literature.
Tsangnyön Heruka was a nyönpa (Wylie: smyon pa) or "religious madman", whose eccentric ways of life were considered signs of spiritual realization. He was ordained as a śrāmaṇera, but at the age of 21 renounced his vows and trained under various tantric yogis from different schools. His first teacher was Shara Rabjampa Sanggye Sengge (1427–1470) who conveyed to him the "Aural Transmissions" (snyan brgyud) of the Kagyu tradition. Tsangnyön spent years in solitary retreat on Tsari in southern Tibet, which is the major sacred mountain retreat for the Kagyu school. He also studied the tantras in Pelkhor Chode Monastery in Gyantse for three years.
After Heruka left the monastery, he became a wandering yogi for the rest of his life, never staying in one place permanently. He was known to keep his hair long, carry a khaṭvāṅga and drink from a kapala. When local villagers saw his body covered in human ashes and blood with his hair adorned by human fingers and toes, they gave him the name 'Nyönpa' (madman). He later used the name Trantung Gyelpo (Wylie: khrag 'thung rgyal po) "King of the Blood-drinkers", "blood drinker" being the Tibetan name for the deity Heruka. These eccentric ways were influenced by an Indian sect of yogis called Kapalikas or "skull-bearers", who practiced austerities as well as dressing in loincloths and human ashes and carrying symbols of the dakinis such as bone ornaments and skulls.