According to Legend of Qinghai (传说青海), a long time ago, the King of Dragons was very happy to see that his queen had given birth to four dragons. Many years later, the four dragons grew up, causing more and more mischievous pranks until the Dragon King was out of breath. One day, the King of Dragons came up with a way to summon all the dragon princes into the Crystal Palace. He said, "You have grown up, so you should all have your own side." Then he ordered the eldest prince Ao Guang to become the King of the East China Sea, the second prince Ao Qin to become the King of the South China Sea, and the third prince Ao Shun to become the King of the North Sea. The King of Dragons wanted to keep the little prince Ao Run beside him, but Ao Run said, "I will be the King of the West Sea!" The King of Dragons laughed and praised him. Beyond the Huaxia's Nine Provinces, Ao Run did not see the West Sea. When he came to the southern foot of Qilian Mountain, he was exhausted. He cried sadly, "How can I be the King of the West Sea without the West Sea?" Then he climbed to the top of Qilian Mountain and made a big storm, but it did not suffice. When the Jade Emperor saw this happen, he felt pity. Therefore, he sent Lord of Thunder, Mother of Lightning, Earl of Wind, and Youth of Cloud to help Ao Run. Lightning, thunder, and storms created Haizi with an area of more than 5,000 square kilometers and a depth of more than 20 meters, which became the West Sea (Qinghai Lake). Since then, Ao Run has become the Dragon King of the West Sea.[4]
Ao Run has three children. His sons are Ao Lie, who was the steed of
Tang Sanzang, and Ao Moang (敖摩昂). He has a daughter named Ao Cinxin (敖寸心), also known as the Xihai Longnü (西海龙女).