Xun Yu
Cao Cao had originally wanted to follow up his victory over Yuan Shao by turning south to attack Liu Biao and Sun Quan, the latter who had newly inherited his domain from his deceased brother Sun Ce. Cao Cao's strategist Xun Yu cautioned against such action, reasoning that Cao Cao should take the opportunity to settle the matter with Yuan Shao, who was now facing internal turmoil after his recent defeat. Xun Yu also realized the danger of turning the focus to the south at such a time, since the remnants of Yuan Shao's men might band up and attack Cao Cao's rear. Cao Cao then gave up on the idea and continued the campaign against Yuan Shao.