長平の戦い
At their peak, Chu and Qin together fielded over 1,000,000 troops, more than the massive Battle of Changping between Qin and Zhao 35 years before. The excavated personal letters of two regular Qin soldiers, Hei Fu () and Jing (), tell of a protracted campaign in Huaiyang under Wang Jian. Both soldiers wrote letters requesting supplies of clothing and money from home to sustain the long waiting campaign.