[1] When the Emperor Taizong of the Tang was being plagued by nightmares, he ordered portraits of his generals Qin Shubao and Yuchi Gong to be affixed to gates.

[citation needed] They eventually came to be considered divine protectors, replacing Shentu and Yulü and remaining the most common door gods to the present day.

[1] Qin and Yuchi, along with various other deified military leaders, make up a class of martial door gods intended to ward off evil spirits and bad influences.

The annoyed spirit of the Dragon King then haunted the Great Ancestor each night until his generals Qin Shubao and Yuchi Gong volunteered to stand guard at his door.

[2] In modern China, door gods do not make up a formal element of Taoism and are included as traditional decorations or as nods to popular superstition.

[1] There are, however, some deities worshipped for other reasons—including the Azure Dragon,[4] the White Tiger,[4] and Mazu's companions Qianliyan and Shunfeng'er—who also serve as door gods at Taoist temples.

1983 Shaw Brothers Movie Of Ghosts Galore Starring Chin Siu Ho And Chiang Kam In A Final Fight Against A Japanese Sorcerer (Hwang Jang Lee).