Late Han Three Kingdoms: Building an Empire on the Frontier

[Transmigration + alternate history + farming and conquest + no System] A modern soul transmigrates into Gongsun Du at the end of the Han Dynasty, facing a dead end from the start. In the imperial palace, he cleverly invents an auspicious omen sent from heaven to win himself a chance at survival. He then stakes the lives of his entire clan and pledges to find a way to return home. After returning home, he promotes farming colonies, reforms the administration, and trains elite troops. He defeats the Xianbei to the north, destroys Goguryeo to the east, and pacifies the Three Han states to the south. While the warlords of the Central Plains remain locked in endless conflict, he has already built a powerful empire in the northern frontier, with abundant troops and supplies!