Po Riyak, the 'Lord of the Waves', is the Cham deity of the sea and the storm. His legend tells of a young Cham who sailed abroad — to Kelantan or, in Islamic-tinged versions, to Mecca — to master sacred and magical knowledge, but who, forbidden or unable to complete his return, perished in the waters off the coast. Transformed into a spirit of the waves, he became the guardian of fishermen and seafarers, and his power is felt in the great whale that carries drowning men safely to land, tying his cult to the whale veneration shared along the south-central Vietnamese shore. Offerings are made to him for calm seas and good catches; he stands among the yang of the Cham as the one god born wholly of the ocean.