张道陵
From the idea of Taoism, Guang Chengzi was the avatar of Taishang Laojun (also named Daode Tianzun) during the period of Yellow Emperor in ancient Chinese history. According to Zhuangzi's recording, he lived in Kongtong Mountains, the Yellow Emperor visited him there for his teaching. He gave the Yellow Emperor several books that talked about the moral, natural, and philosophical issues, which helped the Yellow Emperor create the early Chinese civilization. It is said that Guang Chengzi had a long life of 1200 years. There is another saying that Guang Chengzi was the avatar of the Dao, who appeared in the human world three times – the first time as Guang Chengzi during the Yellow Emperor time; second as Laozi during the Spring and Autumn period; and third time as Zhang Daoling in the Han Dynasty.