Apam Napat
The Child of the Waters: a golden god who shines in the depths of the waters without fuel, nursed by the young Waters, clothed in lightning when he rises into the cloud. One hymn is his (RV 2.35), whose last verse addresses Agni; two verses of RV 10.30 call on him, and he is named about thirty times. Agni is elsewhere called the Waters' Child outright. In the Soma ritual an offering is made to him when the water is fetched, with the hymn first seen by Kavasha Ailusha. The Avesta of Iran honours a god of the same name who lives beneath the waters.
Sources: Hymns of the Rigveda, tr. R. T. H. Griffith (1896), hymns read for the Vedic layer; Vedic Mythology, A. A. Macdonell (1897); The Zend-Avesta part II: Zamyad Yasht (Yasht 19), tr. James Darmesteter (Sacred Books of the East 23) · see Apam Napat's web