 Court officials Wang Yun, Huang Wan (黃琬), Shisun Rui (士孫瑞) and Yang Zan (楊瓚) plotted to assassinate Dong Zhuo.They persuaded Lü Bu to join their cause because Lü's relationship with Dong was becoming increasingly strained after Dong threw a hand-axe at him and due to his affair with one of Dong's chambermaids.On 22 May 192, Dong Zhuo was on the way to an assembly in his chariot when Li Su advanced towards him and stabbed him.