Legend has it that the lower eye of Zhulong Jiuyin is yang, which is the source of all spirits, and the upper eye is yin, which connects the Nine Nether Hells and is called the gate of hell. When Emperor Shun was in power, in order to permanently close the gate of hell, he gathered all the great gods and went to Zhongshan where he lived. They fought for several months and finally killed him. After Zhu Jiuyin died, all his energy focused on his eyes. The upper eye was yin and turned into the eye of the inner demon. The lower eye was yang and turned into the Ten Thousand Saint Longzhu.
After the death of Zhulong, he left behind a clan of descendants, the so-called Demonic Dragon Clan, formerly the Chiyou Clan and also called the Jiuli Clan. The Demonic Dragon Clan used Zhulong as their totem all their lives and believed in the Heavenly Fire. They were born with a bronze head and iron arms and were invulnerable. They had strong reproductive abilities and it didn't take long for the entire clan to defend the throne. The then-reigning Emperor Yu, in order to show himself to be a virtuous man, exiled the Demonic Dragon clan on the surface, but secretly used the Eye of the Inner Demon to cast a blood curse and cut off its inheritance. The Demonic Dragon clan, protected by the soul of the candle dragon, had no choice but to move underground, and with the help of the power of the earth's fire, they managed to reproduce.
Times have changed, and thousands of years have passed in the blink of an eye...