NAGA , semi-divine snakes with human faces and serpent tales, reside in a watery underground region called the Patala. Udyana, in modern Pakistan, was famous for its water dragons. Buddha converted Apalala to Buddhism.
APALALA, a Naga water dragon, lived at the source of the Swat river and prevented wicked dragons from scourging the countryside with violent rainstorms. The countryside prospered, grain grew densely and in gratitude each family offered tribute with a small quantity of grain. As time passed, inhabitants started to forego the yearly offering. Becoming angry, the Naga serpent prayed for transformation into a poisonous dragon so that he could drench the countryside in rain and wind. On his death he became the dragon of the country and today Rajas (local princes) of the Hindu Kush are able to control the elements because of their influence over local dragons.
Asian dragons are associated with the life-giving waters.