Qinglong, Baihu, Suzaku and Xuanwu, also known as the Four Elephants, are the four gods in China mythology, representing the east, west, south and north respectively. They originated from the belief in the stars in ancient China, not Taoism, and were not absorbed by Taoism until the Han Dynasty.
In China after ancient times, the male dragon had horns on his head; Double horns are called dragons, and single horns are called dumplings; Those with horns are poisonous snakes. In ancient times, there were often large and small Ssangyong in Yu Pei, and it was still called mother and son poisonous snakes. Because it is sacred and supreme in the dragon, it is also a symbol of the emperor. It is also the representative of the east, and the five elements belong to wood. Because cyan belongs to wood, there is the saying of Zuo Qinglong and you Bai Hu.
Extended data:
Four elephants are the guardians of the Quartet. According to Three Auxiliary Huang Tu, black dragon, white tiger, suzaku and Xuanwu are the four spirits of the sky. Zuo Qinglong, You Baihu, Thousand-legged Sanzang, Houxuanwu, and the four great beasts respectively guard the four palaces in the east, west, north and south, and are the gods of the four directions.
Later, the four elephants were gradually personified by Taoism because of their absorption and evolution, and were given the title, namely, Qinglong, Baihu and Suzaku. Xuanwu is the "Ming King".
Baidu Encyclopedia-Four Great Beasts