공손찬
In 192, Liu Dai, the Inspector of Yan Province, invited Cheng Yu to join his administration but Cheng Yu refused. At the beginning, Liu Dai had very good relationship with the warlords Yuan Shao and Gongsun Zan, wherein Yuan Shao sent his family to reside with Liu Dai while Gongsun Zan sent a detachment of elite cavalry to help Liu Dai fight the Yellow Turbans in the area; however, Yuan Shao and Gongsun Zan became bitter enemies later, and were way more powerful than Liu Dai, who was forced to pick a side. Liu Dai then sought advice from Cheng Yu, who told the former that asking for help from Gongsun Zan was like requesting someone to save a drowning child from afar. He further analysed that Gongsun Zan, who had recently gained a minor military victory over Yuan Shao, would eventually lose to the latter. Therefore, it was not wise to enjoy a short-term benefit without a careful long-term plan. Liu Dai agreed with Cheng Yu's speech and severed ties with Gongsun Zan, who ordered his cavalry in Yan Province to return to his base in You Province. Just as Cheng Yu had predicted, Gongsun Zan soon suffered a heavy defeat by Yuan Shao before his cavalry could even join the battle. Liu Dai then asked Cheng Yu to become his officer, and offered him the position of a Cavalry Commandant, but Cheng Yu again refused employment.