There is no such person as Patriarch Hongyun in ancient Chinese mythology. This character is a fictional character from Chinese mythology and legend created in the well-known online novel "Buddha is the Tao".

Note: The following content comes from "Buddha is the Tao" or "Prehistoric Novels"

Ancestor Hongyun was the first red cloud in heaven and earth to attain the Tao after the heaven and earth first opened. The strength of Saint (Daluo Jinxian). I once listened to Hongjun's sermon in Zixiao Palace with the Six Saints of the Ancient World, Donghuang Taiyi, Dijun, Zhen Yuanzi, Kunpeng and others. Hongyun has a good nature and is willing to help others. He has made many friends in the primitive world. During the primitive period, many people with great supernatural powers who listened to the Tao were friendly to him. And he is also the most unlucky person in the world.

Kunpeng, Taiyi, Dijun, and Minghe attacked Hongyun halfway, but Hongyun was unable to defeat him and died in the end.