Guo Tu
When Yuan Shao's camp received the news that Wuchao was under attack, Zhang He urged Yuan Shao to send reinforcements to Wuchao to save the supplies, on which the fate of the campaign hinged. Guo Tu, however, advocated the opposite: attack Cao Cao's base at Guandu with the hope that Cao Cao will abandon the raid on Wuchao. Yuan Shao used Guo Tu's idea and sent Zhang He and Gao Lan to lead his main army to attack Cao Cao's main camp at Guandu, while only sending a small cavalry unit to reinforce Wuchao.