Lee Zicheng’s invasion of the Forbidden City, Emperor Chongzhen has resisted all the way and finally hangs himself on Meishan upon his failure. Princess Kunxing (Changping) vows to keep the Forbidden City from falling into the hands of traitors, but is at a loss for what to do. Only by finding the legendary Zhanxian Sword, can she solve her dilemma. How will Solar who is involved in the war defeat the legendary beasts, namely Qiuniu, Yazi, Jiaotu and Taotie? What should Bixi, the sixth son of the dragon who shares a brotherhood with these beasts and also a friend of the princess do?