Yamāntaka

Yamāntaka or Vajrabhairava is the "destroyer of death" deity of Vajrayana Buddhism. Sometimes he is conceptualized as "conqueror of the lord of death". Of the several deities in the Buddhist pantheon named Yamāntaka, the most well known belongs to the Anuttarayoga class of tantra of deities popular within the Gelug school of Tibetan Buddhism.

Etymology
Yamāntaka is a Sanskrit name that can be broken down into two primary elements: Yama (यम), –the god of death; and antaka (अन्तक) –destroyer. Thus, Yamāntaka means “Destroyer of Death” or "Conqueror of Death".
While Yamāntaka is therefore Yama's nemesis, his representation mirrors Yama in many ways: he too often rides a buffalo and is often depicted with a buffalo's head.
Because of this mirroring of appearance and similarity in name, it is not hard to find texts and books (which would appear to be reliable sources of much material) conflate both Yamāntaka and Yama as being the same deity when they are not.
Within Buddhism, "terminating death" is a quality of all buddhas as they have stopped the cycle of rebirth, samsara. So Yamāntaka represents the goal of the Mahayana practitioner's journey to enlightenment, or the journey itself: On final awakening, one manifests Yamāntaka – the ending of death.

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