(“descent”), in Hinduism, the incarnation of a deity in human or animal form to counteract some particular evil in the world. The term usually refers to these 10 appearances of Vishnu: (Vishnu) Matsya (fish), Kūrma (tortoise), Varāha (boar), Narasiṃha (half man, half lion), Vāmana (dwarf), Paraśurāma (Rāma with the axe), Rāma (hero of the Rāmāyaṇa epic), Krishna (the divine cowherd), Buddha, and Kalkin (the incarnation yet to come). The number of Vishnu's avatars is sometimes extended or their identities changed, according to local preferences. Thus, Krishna is in some areas elevated to the rank of a deity, and his half brother, Balarāma, included as an avatar. One formulation of the doctrine is given in the religious poem the Bhagavadgītā (Bhagavadgita), when charioteer Lord Krishna tells Arjuna: “Whenever there is a decline of righteousness and rise of unrighteousness then I send forth Myself. For the protection of the good, for the destruction of the wicked, and for the establishment of righteousness, I come into being from age to age.”