Varuna

Lord of the skies and of the heavens, protector of order and morality, Varuna was initially a supreme god but was gradually deprived of his roles by other Vedic gods.  Finally, his position as guardian of the western territories was attributed to Vishnu.

In Angkor temples, he is represented riding a Hamsa, or sacred goose.  Later, he became a god of the ocean and rivers, and is depicted riding a makara.