Shyena (Sanskrit: श्येन ) is the divine hawk identified with Agni, who ascends to heaven for bringing soma (nectar) to earth with the intention of rejuvenating and revitalizing of all things that exist on earth. It also refers to the fire-altar constructed with bricks (Agni Chayana) in the shape of a hawk (symbolizing the essence of Agni) in the Vedic ritual. The Yajurveda prescribes prayers and mantras meant to be recited during the course of the construction of this fire-altar which represents the creator and the created. In the Puranas, Shyena becomes Garuda, the vehicle of Lord Vishnu, which finds mention also in the Adi Parva of the Mahabharata, and who brought amrita from heaven at the behest of Kadru, the mother of serpents and a co-wife of Rishi Kasyapa.