司马懿
At the time, Li Sheng, one of Cao Shuang's supporters, had been recently reassigned to be the Inspector of Jing Province. Cao Shuang secretly instructed him to check if Sima Yi was as ill as he claimed, so Li Sheng visited Sima Yi before leaving for Jing Province. Sima Yi knew the true purpose of Li Sheng's visit, so he pretended to be frail and senile. Li Sheng saw that Sima Yi could not move around and wear clothes without help from his servants, and could not even consume congee without soiling his clothes. He then told Sima Yi: "Everyone thought that your illness was a minor one; alas, who expected you to be in such poor health?" Sima Yi pretended to cough and pant as he replied: "I am old and sick and I am going to die soon. When you go to Bing Province, you should be careful because it is near barbarian territory. We might not see each other again, so I entrust my sons Shi and Zhao to your care." Li Sheng corrected him: "I am returning to my home province, not Bing Province." Sima Yi pretended to mishear and continued saying: "You are going to Bing Province, aren't you?" Li Sheng corrected him again: "My home province is Jing Province." Sima Yi replied: "I am so old and weak that I can't even hear you properly. So now you are going back to your home province. It's time for you to make some glorious achievements!" Li Sheng returned to Cao Shuang and told him: "Sima Yi is dying soon and no longer of sound mind. There's nothing for you to worry about." Later, he said: "It's sad to see that the Grand Tutor is no longer in a good state of health to serve." Cao Shuang lowered his guard against Sima Yi.