A modern working stiff transmigrates to become Zhu Yuanzhang's second legitimate son, Zhu Shuang, and is born into the chaotic times of the late Yuan dynasty. The system that awakens at the start unexpectedly crashes, leaving behind only an ultra-strong physique and ten thousand Dragon Cavalry Guards. Young Zhu Shuang acts mischievously and roasts the court nobles and officials everywhere while secretly accumulating strength. Following his father and elder brother to pacify the world, he captures the Northern Yuan imperial family alive during the northern expedition, making illustrious military achievements. Invested as the Prince of Wu, he vigorously pushes forward the new policy of apportioning land tax into grain tax, goes south to the Jiangnan region to overhaul officials, tries out official reforms, and protects his elder brother Zhu Biao's stable position as crown prince, walking a passionate and swaggering path of a vassal king amidst the turbulence of the early Ming dynasty.