李罕之
Meanwhile, Zhang initially had a cordial relationship with Li Hanzhi, whose Heyang Circuit his Henan Municipality belonged to, and they even cut their own arms to swear to be brothers. However, Li Hanzhi viewed Zhang's promotion of farming lightly. He also made a habit of making all kinds of material demands on Zhang, to the point that whenever he was not satisfied with what Zhang supplied his army, he would arrest Zhang's subordinates and cane them. Initially, Zhang put on the appearance of fearing Li Hanzhi and doing everything to appease him. In 888, when Li Hanzhi was on a campaign against the army of Huguo Circuit (護國, headquartered in modern Yuncheng, Shanxi), Huguo's military governor Wang Chongying sent secret emissaries to persuade Zhang to turn against Li Hanzhi. Zhang agreed, and he launched a surprise attack on Heyang at night, capturing it and taking Li Hanzhi's household captive. He then claimed the title of military governor of Heyang for himself.