Kalki

Kalki (Sanskrit: कल्कि), also called Kalkin, is the prophesied tenth and final incarnation of Hindu God Vishnu to end the Kali Yuga, one of the four periods in the endless cycle of existence (Krita) in Vaishnavism cosmology

The end of Kali Yuga states this will usher in the new epoch of Satya Yuga in the cycle of existence, until the MahaPralaya (the Great Dissolution of the Universe)

Kalki is described in the Puranas as the avatar who rejuvenates existence by ending the darkest and destructive period to remove adharma and ushering in the Satya Yuga, while riding a white horse with a fiery sword

The description and details of Kalki are different among various Puranas

Kalki is also found in Buddhist texts, for example the Kalachakra-Tantra of Tibetan Buddhism

The prophecy of the Kalki Avatar is also told in Sikh texts