 After his appointment, Han Xin analysed the situation for Liu Bang and devised a plan for Liu to conquer Xiang Yu's Western Chu kingdom.In late 206 BC, Liu Bang's forces left Hanzhong and prepared to attack the Three Qins in Guanzhong.Han Xin ordered some soldiers to pretend to repair the gallery roads linking Guanzhong and Hanzhong, while sending another army to secretly pass through Chencang and make a surprise attack on Zhang Han.