Divining the Heavenly Mechanism

In the Tongguang era of the Later Tang Dynasty, on the eve of the war to destroy the Liang Dynasty. Gu Yan, a conscripted grain transporter who transmigrated into the past, narrowly escapes death on the execution ground after using an old copper button to glimpse the secret of a Liang army spy. He discovers he has gained a strange ability—by touching hidden secret objects, he can read residual memories. The cost is nosebleeds, headaches, and the danger of being targeted by those in power. Li Siyuan, the deputy commander of the Fan-Han cavalry and infantry, takes in this 'nail.' But in this military camp, some want to use him, some want to kill him, and some want to uncover his origins through him—while Gu Yan himself doesn't know whose body he has occupied. In the Five Dynasties and Ten Kingdoms period, human life is as fragile as grass. He must survive among the blades, and while alive, figure out one thing: who am I? — Description from novelcodex.org