Amid the chaos of the An Lushan Rebellion in the Tang Dynasty, with monsters rampant and the Central Plains in despair, Li Haobai, originating from Bashu, embarks on a journey to the battlefield to seek glory. However, his path takes a dramatic turn when he gets consumed by a monster. Through a twist of fate, Li Haobai merges with the guardian of the dragon's veins, attaining the potent abilities of the black dragon. Thus ensues his entanglement in the conflicts among different factions.