Yuan Shao who was a leader in Hebei let his general Yan Liang, as avant-courier, attack White-horse Po. The several generals of Cao Cao were failed by Yan Liang,. Cheng Yu recommended Guan Yu, Guan Yu rode with his blue dragon sword, running down from the hill. He rushed into Yan Liang's army directly. Yan Liang was impermissible to evade and was pulled down from the horse. Guan Yu killed him with his sword, attached his head on the horse neck, and rush off the army with his sword. The soldiers and generals of Hebei were all surprised by him and their army was in confusion.