Cao Cao killed many people for his ambition, and he killed his childhood playmates, both those who opposed him and those who took refuge in him. Because Cao Cao's father was the adopted son of the eunuch, his childhood playmates called him "an extra eunuch who left an ugly legacy", and it was for this reason that Cao Cao's character was very extreme.
Cao Cao's childhood playmates were mainly Zhang Miao, Yuan Shao, Juck Zhang and Lou Gui, and Yuan Shao's family was very powerful. Even if he was defeated by Cao Cao, Cao Cao had to spend a lot of energy to remove the remaining family power of Yuan.
Xu You is different from Yuan Shao. He is not an enemy of Cao Cao, but a teammate of Cao Cao. After the battle of Guandu, he took refuge in Cao Cao and repeatedly made meritorious military service. However, Xu You is proud of his achievements and often calls Cao Cao by his nickname to his face. Cao Cao couldn't bear it, and finally killed him.
Zhang Miao was originally under the command of Cao Cao, but after Cao Cao killed Bian Rang's family, Zhang Miao chose to take refuge in Lu Bu. When Cao Cao knew this, he immediately sent troops to attack Lu Bu, and finally Lu Bu was defeated, so Zhang Miao was killed by Cao Cao.
Lou Feng followed Cao Cao for many years and was deeply trusted, but he was killed by Chu Xu because of a few words. When Cao Cao returned victorious, his two sons went to meet him. Shou saw that all three people were happy and praised him. Unexpectedly, Lou Gui advised him not to talk about others at will. When Cao Cao heard Loufan's words, he asked Chu Xu to kill Loufan.