Zhang Ni
Zhang Ni previously observed that Fei Yi had become General-in-Chief but he was unrestrained by nature and careless in showing favor. Hence, he was excessive in his trust and good treatment of newcomers to his following. Zhang Ni sent a letter to admonish him that said: "In the past Cen Peng was a great commander wielding Staff of Authority, but was killed by an assassin. Now you wise General occupy a position of great power and importance and should reflect on past events. You should act less careless on guard." Later Yi was indeed killed by a surrendered Wei man Guo Xiu.