Xiaren traveled through the Tang Dynasty and became the crown prince Li Chengqian. He was dissatisfied with Li Shimin's favor for Li Tai, so he launched the Xuanwu Gate Revolution. Unexpectedly, Li Shimin secretly set up an ambush, causing the Xuanwu Gate Revolution to fail. After the Xuanwu Gate failed, Li Chengqian killed Li Tai and Li Zhi, forced Li Shimin to the palace with iron-blooded means, and gradually took control of the power of the Tang Dynasty. He purged the noble families, reformed the military system and official selection system, developed gunpowder firearms, used thunderous means to eliminate foreign invaders, and even developed cowpox to eradicate smallpox. Finally, it was recognized by Li Shimin
