Hangu Pass
Between 190 and 191, when Dong Zhuo was at war with a coalition of warlords from the east of Hangu Pass, Niu Fu deployed troops to defend the strategic mountain passes leading into Luoyang. At the same time, he also sent Dong Zhuo's other subordinates, such as Li Jue, Guo Si and Zhang Ji, to lead soldiers to raid and pillage Chenliu (陳留) and Yingchuan (潁川) commanderies, as well as attack the general Zhu Jun at Zhongmu County (中牟縣).