Mrtyu

Mṛtyu (from Vedic Sanskrit: मृत्यु IAST:mRtyu ; Latin cognate mortis), is a Sanskrit word meaning Death. Mṛtyu or Death is often personified as the demigods Mara (मर) and Yama (यम) in Dharmic religions such as Hinduism and Buddhism.

The Brhadaranyaka Upanishad (a mystical appendix to the Shatapatha Brahmana and likely the oldest of the Upanishads) has a creation myth where Mṛtyu "Death" takes the shape of a horse, and includes an identification of the Ashvamedha horse sacrifice with the Sun:

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