(If you don’t want to read about the events from the Xuanwu Gate Incident to the Alliance at the Wei River, you can skip straight to Chapter 10.)
A modern young man transmigrates after working himself to exhaustion, awakening in the body of Li Kuan, Li Shimin’s second son, who died young in the Tang dynasty. Reborn, Li Kuan struggles to survive in the wilderness in the body of a mere three-year-old. Thanks to his modern knowledge and mature mind, he makes it to the age of six and reaches Chang’an. Soon after, Li Shimin spots him begging on the streets of the city...
Li Shimin takes him back to Chang’an, and from then on, Li Kuan makes plans across the Tang dynasty, embarking on a path unlike that of anyone who came before him...
(To make the story as detailed as possible, the pacing may be a little slow.)