As mentioned earlier, in the face of Yuan Shao, whose strength was several times greater than his own, Cao Cao actually had the psychology of eager to try. And before the war began, Cao Cao greatly boosted morale through his own clever means, so that the entire Cao Cao clique was united in hatred with the enemy. In this situation, Cao Cao also took the lead in attacking.
Cao Cao's first plan was to occupy Hanoi in order to sneak up on Yecheng. In February of the fourth year of Jian'an (199 AD), a series of changes occurred in Hanoi County, first the Hanoi Taishou Zhang Yang was killed by the general Yang Ugly, and then the Montenegrin army Xiao Gu killed Yang Ugly. After Xiao Gu and others occupied Hanoi, they immediately threw themselves into Yuan Shao's command. The far-sighted Cao Cao suddenly came up with a good idea, he planned to occupy Hanoi, and then sneak attack on Yuan Shao's strategic stronghold of Yecheng. Once Cao Cao had gained the rich city of Yicheng, Cao Jun's grain and grass problems could be greatly improved, and Yuan Shao could become tied.
According to the Chronicle of the Three Kingdoms? The Records of Emperor Wu records that Cao Cao's movements were swift, and in April of the same year, he suddenly launched a fierce attack on Hanoi County, "marching into linhe, so that Shi Zhuo and Cao Ren crossed the river to attack it." Caught off guard, the Black Mountain thieves were defeated, and Hanoi quickly fell into the hands of Cao Cao: "Great destruction, cut solidity, gong Sui Ji River, surround the dog." Just as Cao Cao was preparing to continue to attack Yecheng to the east, Yuan Shao suddenly returned to defense. Cao Cao's action was extremely fast, and he was fighting a surprise attack, and it was reasonable to say that Yuan Shao's reaction could not be so fast. After the plan to sneak into Yecheng was aborted, Cao Cao received a message and knew what the problem was.
Apparently, Cao Cao's own battle plan was leaked, and the informant was None other than Liu Bei, who seemed benevolent, loyal, and honest. To be fair, Cao Cao was indeed very good to Liu Bei. According to the Chronicle of the Three Kingdoms? The Biography of the Ancestor records that after Liu Bei Lübu was driven out of Xuzhou, he was treated favorably by Cao Cao. Cao Cao first "took (Liu Bei) as the pastor of Yu Prefecture, collected and scattered soldiers, and gave him military food", helping Liu Bei to collect his own remnants, and then again crowned Liu Bei as a general of the left, "the heavier the ceremony, the more the public opinion, and the seat is the same seat". And Liu Bei's greatest ability is that mood and anger are not colorful. While complimenting Cao Cao, he said a lot of good things; on the other hand, he and Dong Cheng and others participated in the YidaiZhao incident in a vain attempt to get rid of Cao Cao.
But what Liu Bei wanted to do most was actually to get rid of Cao Cao's coercion, so he set his sights on Yuan Shao. Because of this, when Cao Cao attacked Hanoi, Liu Bei quickly betrayed him in order to gain Yuan Shao's trust. And to investigate, there is also an opportunity. According to the Chronicle of the Three Kingdoms? The Records of Emperor Wu records that Yuan Shu was desperate at that time, and eventually planned to pass by Xia Pi and go to his brother Yuan Shao. When Liu Bei heard the news, he took the initiative to ask Miao to go and block Yuan Shu. Beforehand, Cheng Yu and Guo Jia also felt that Liu Bei was an anti-bone boy and felt that they could not let him go. But Cao Cao was very confident, and not only sent Liu Bei to Xuzhou, but also allocated an army to him.
Soon, Liu Bei's practical actions explained that his name of "big ear thief" was not in vain. "To Xia Pi, he killed Xuzhou's assassin Shi Che and raised an army to raise troops. (Cao Cao) sent Liu Dai and Wang Zhongzhi to attack him, but he did not take it. "There is a question that needs to be solved, why can Liu Bei quickly occupy Xuzhou? There are two main reasons, one is that Liu Bei had previously served as the pastor of Xuzhou, and his name of benevolence gave him a large mass base; the other is that after Cao Cao captured Xuzhou, in order to avenge his father (his father Cao Song's family had been killed by Xuzhou generals), he did not hesitate to make a move to slaughter the city for posterity. With such a comparison, Liu Bei was naturally able to take over Xuzhou smoothly.
According to the Chronicle of the Three Kingdoms? The Biography of the Ancestors records: "The East China Sea Chang hegemony rebelled, the counties rebelled against Cao Gong as the first lord, tens of thousands of people, sent Sun Qian and Yuan Shao lianhe. After Liu Bei betrayed Cao Cao, Changba and others in the East China Sea also took the opportunity to rebel and responded to Liu Bei's call to form an alliance with Yuan Shao. The situation in Cao Cao's group at this time was immediately in the ascendant. Because after Liu Bei and Yuan Shao joined forces, they could attack Cao Cao at any time. In this situation, Cao Cao made a bold decision, that is, to blitz Xuzhou.
According to the Chronicle of the Three Kingdoms? According to the Records of Emperor Wu, after Cao Cao revealed his plan, the courtiers were puzzled, believing that Yuan Shao could attack from the rear at any time. In this regard, Cao Cao made up his mind: "Husband Liu Bei, Ren Jieye, if you don't attack now, you will definitely suffer trouble in the future." Although Yuan Shao had great ambitions, he would not move when he saw things late. Guo Jia, who had always understood Cao Cao's thoughts, also immediately approved of attacking Liu Bei.
After Liu Bei occupied Xuzhou, he ordered the general Guan Yu to garrison the strategic point of Pi, while he himself personally came to Xiao Pei, ready to cooperate with Yuan Shao in attacking Cao Cao at any time. Under these circumstances, Cao Cao still chose to attack Liu Bei. It is reported that there are more than 800 huali from Guandu to Xiaopei, and more than 200 huali from Xiaopei to Xiapi. Once Cao Cao attacked Liu Bei, then he could only make a quick decision and fight a beautiful blitzkrieg. Therefore, Cao Cao personally led the main force to directly launch an attack on Liu Bei, and it only took ten days to arrive at Xiao Pei. Liu Bei, who was still waiting for Yuan Shao's support, immediately panicked. It didn't take long for Cao Cao to easily take Xuzhou, "Broken, raw bird and general Xiahou Bo." Ready to go to Benshao, get his wife. Prepare the general Guan Yu tun down Pi, resume the attack, and yu descend. Chang Feng rebelled and prepared for it, and then attacked it."
Focusing on Yuan Shao, the behavior of the jun was very strange. In the two months from December of the fourth year of Jian'an (199) to the first month of the fifth year of Jian'an, Yuan Shao did not have any military deployment. According to the Chronicle of the Three Kingdoms? The biography of Yuan Shao records: "In the fifth year of Jian'an, Taizu marched from the east to prepare. Tian Feng said that after Shao attacked Taizu, Shao resigned to the disease of the son, and did not allow it, and Feng raised his staff to hit the ground: "The husband suffered a chance to meet the enemy, and he lost his meeting with the illness of the baby, sorry!" From this account, Yuan Shao's logic is really impressive, and he actually ignored Cao Cao's military actions because his young son was ill.
What Liu Bei did not expect was that while he was struggling in Xuzhou, Yuan Shao was worried about his son's illness all day. It was precisely because of Yuan Shao's inaction that Liu Bei was defeated and left, losing his wife and the general Guan Yu. I am afraid that Liu Bei did not expect that his clever act of temporarily betraying Cao Cao would be pitted by Yuan Shao, a "pig teammate".
Reference book: Romance of the Three Kingdoms