In remote antiquity, twin brothers – the Green Dragon and the Yellow Dragon – were living inside Green Creek Cave just located by the side of Xumi Mountain (须弥山). They detested evils and often fought with Wang and Liang (魍 and 魉), the two fierce devils resided along the East China Sea. 

One year, a great drought occurred on earth and everything complained to the Heaven. The Buddha knew the twin dragon brothers knew clearly all about the righteousness on earth; therefore, He dispatched the two to save the world. 

It did not take long time, the twins learnt that Wang and Liang were demons who were doing evils to people. They descended and distributed their sons and grandsons to set fire on the planet and implanted a kind of “hellish fire” in human’s heart. People who had this illness would do bad things and cause troubles to each other. They provoked chaos to the cool and happy world. However, because the charm of the active fire made many people had followed and worshipped it.

For world peace and righteousness, the Green and Yellow Dragons decided to eliminate the evils. The twins disguised themselves as monks. They went to the people’s residences and tried to cure the evils inside them. 

Because of the pestilence inflicted by Wang and Liang, most of the people on the planet suffered a disease called Yan (魇), which, the symptom was that a person would relieve or feel better for a while after he or she did some dirty tricks or evil behavior to others. The monk “doctors” gave people vermilions, pearls and seaweeds to take as remedy, also the taught them to say and repeat a curse to expel the devilish sickness. After using this set of therapy, many patients resumed their goodness and eliminated their ailments. The rehabilitated people told others about the effectiveness of the therapy and so many patients would follow. Three months later, tens of thousands people resumed their normal life by taking the therapy. People talked to each other that it was the merit of the two supernatural beings! 

Wang and Liang learnt that someone who knew their evil spells they sent their best generals, crocodile and toad, to the earth and investigate the facts behind. The tricky and wicked toad persuaded the simple-minded but cruel crocodile to disguise itself to become two patients, asking for treatment, mixing among the crowd and living in the place where the two monks resided. The toad, which had practiced magic spells for more than a thousand years and great spiritual power, could see the holy lights emitted from the two monks. It knew that they were quite powerful. However, it told the crocodile that they were just the lesser gods, they were unimportant, the crocodile should rest and the toad could catch the two lesser gods for its masters. The crocodile was very angry that it thought the toad would attain the whole merit! At this stage, it became the native God. He opened his chopper-like mouth with teeth and marched straightforward to the monks. 

The two monks had already known the two evil spirits would come. They were calm. When one of the monks saw the crocodile was coming straight-ahead, he took a small dragon ball, aimed at the monster and tripped it on the floor. The crocodile realized the situation was unfavorable it managed to escape. However, the other monk used his hand to grasp its head, which was then broken. The crocodile had died. The toad hurried back to the East China Sea, telling Wang and Liang that the enemies were the Green and Yellow Dragons. 

Wang and Liang were extremely angry. They sent evil troops of about 50,000 to challenge the Green and Yellow Dragons. The twin brothers told the people who had been cured staying at their homes and not to go out. They lined up in the heaven and prepared to fight with the devils. Both dragons cast their spells trying to beat the evil forces. It lasted for seven days and seven nights. The two devils realized that lost had been very heavy, but did not accept their defeat. They negotiated and a wicked idea appeared – they would cast evil spells to collect dedicated followers as their soldiers, they arranged and divided them into two gigantic, long snakes – one in the south and another in the north, stretching from east to west, looking like two long strips of fire, wanting to burn out the Chinese soil. They were moving to central China. The places they passed had become charred land. They wanted to destroy the Dragons and kill the cured people. 

The Green and Yellow Dragons had been struggling very hard for days. They were very tired. However, when they saw Wang and Liang attempted to kill all the people they had cured, they decided to save them. The twins ignored all the dangers, they changed themselves to two grand and cold rivers of their corresponding colors. They moved to the fire snakes, forced them to retreat and when they were contacting them, the whole-hearted followers were swirled into the river and died. The twin brothers expelled the devil snakes about 500 kilometers from their original positions before the fighting, which lasted three days and three nights. They pressed the devils under them and eventually the snakes were seriously hurt and buried underground. And the waters to which the dragons made had become the Yangtze and Yellow Rivers. 

Today, the Chinese nation is still multiplying by the feeding of the two great rivers.