In the ninth year of Wude, the heavenly light! The Taibaijin star hangs in the south, at noon! With the change of Xuanwumen, the Tang Dynasty entered the era of Li Erzhang! At the foot of Zhongnan Mountain, Lijiazhuang, there is also a young master Li Xuan! Li Xuan, who wanted to live a carefree, leisurely life in the mountain village. After two years, he had to suppress the boredom and surprise, and shouted in his heart: ... Li Er, I am really not your fourth brother!  …