He is always depicted as an extremely fierce and terrifying deity. ... His purpose is to help in overcoming negative obstacles on the path to enlightenment, and protecting that path of righteousness (also known as “dharma”) from hindrances

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Mahākāla is a deity common to Hinduism, Buddhism and Sikhism. ... Mahākāla also appears as a protector deity known as a dharmapala in Vajrayana Buddhism, particularly most Tibetan traditions as Citipati, and in Chinese Esoteric Buddhism and in Shingon Buddhism