What kind of event is the joke "The dead Zhuge scares away the living Zhong Da"?

From the age of 23, Sima Yi began to advise the Cao Jun Group and join forces to fight. In 234 AD, when Zhuge Liang made his fifth Northern Expedition, Sima Yi led Wei Che to war. Soon, Zhuge Liang died of overwork in Wuzhangyuan military camp. Jiang Wei and Yang Yi, the generals of the Shu army, followed Zhuge Liang's arrangement before his death, secretly deployed and began to retreat to Hanzhong. Sima Yi heard that Zhuge Liang was dead and led an army to pursue him. At this time, Yang Yi obeyed Zhuge Liang's will, slammed the flag, banged drums and pretended to attack Wei Jun. Sima Yi was worried that Zhuge Liang was not dead, but only used a trick to lure the war, so he quickly led the army back to camp. In this way, the Shu army was able to retreat into Hanzhong calmly. From then on, Sima Yi was scared away by the Shu army, and there was a joke that "the dead Zhuge scared away the living Zhong Da".