Magnus Maximus helped Marc invade China's 16 kingdoms, but now they must defeat northern barbarians who use mounted archers and heavy cavalry, and not all the Maximus sons may survive. In the north, Huns under Attila are conquering Avars, so the family must build a new wall to prevent Huns from overrunning China. A lost prince is found, an old enemy returns, and a new total war is on the horizon.