King Riyao Tuosai's beautiful day was being overshadowed.
In his original plan, he would have first sent in a decisive force to decide victory when the Court Attendants Army and King Shengri's army were in the heat of battle. Then he would have worked with Captain Wucuo to divvy up the Court Attendants Army and absorb the largest fraction of it for himself.
Things had started out more smoothly than he expected. The Commandant had been assassinated. With the excuse that he was returning the body, he was able to enter the camp and with that, he had a chance to take over the whole army. He could not have possibly imagined that a group of junior officers would be able to crucially harm his grand plan.