Although Ouyang Xuan knew that Pan Luohuan would inevitably make a moth in the joint attack on Chongqing Mansion with his virtue of retribution, he didn't expect that Pan Luohuan would dare to regard the major affairs of the military state as child's play. It is a miracle that the Southern Song Dynasty court, which used the sons of these families as the foundation of its rule, can support it until now, but it doesn't matter if these decadent classes kill themselves, they have harmed a large number of ordinary people to bury them. He forcibly suppressed the anger in his heart and ordered Cao Ergou to attack the city after the fog cleared tomorrow morning.

In the middle of the night, Ouyang Xuan, who was sleeping soundly, was woken up. He walked out of the tent with sleepy eyes and found Tang Xiangwei and Liao Loach waiting outside the tent. The two men reported that the defenders of the city had several dozen men coming to vote, and since they did not dare to make an unreasonable claim, they let them wait outside the camp gate. Ouyang Xuan knew that this was the effect of Tang Xiangwei and the others shouting before dinner, so he asked the new annex army to collect the weapons of the new annex army in the future, and then bring them into the camp to roast and eat. Most of these defectors were old friends and subordinates of Tang Xiangwei and Liao Loach, and some of them were also familiar with Cao Ergou and Huang Dagen, so they immediately ate around the fire while telling the situation in the city in detail.

The situation in the city was similar to that of the Thunderbolts, and after the Mongol cavalry detachment of 100 men withdrew to Chengdu, there were now less than 600 soldiers, including 50 personal soldiers of the generals who defended the city. Originally, there were more than 600 soldiers in the new annex army, but since the beginning of winter, many people have died of disease due to hunger and cold, and in addition to the continuous flight of people, there are now less than 500 people. The Mongols drove men and women who could pick up clubs to help defend the city, and now the defenders of the city barely numbered a thousand. It's just that Chongqing Mansion City is a big city with a radius of nearly a few miles, and this person can only focus on guarding the four city gates and the north gate where the Thunderbolt army is camped, and the other directions are defended like a leaky sieve, so these defectors found a no-man's place to secretly go down the city. These defectors also told Ouyang Xuan that there was a shortage of food in the city now, and that the new annexed army could only eat half full, except for the generals of the Semu people and their own soldiers. As for the common people, they are even more short of food, and nearly half of the more than 500 households in the city have died of hunger and disease, and there are only more than 1,000 people left, and most of the people who are surviving are yellow-faced and thin-skinned.

Ouyang Xuan also learned that in addition to the low morale of the new army due to hunger and cold, what was more important was the oppression of the soldiers by the generals of the Semu people. The generals and soldiers of this Semu people are all aliens from the Western Regions, well-equipped and powerful, but they are more greedy and cruel than the officials of the Southern Song Dynasty. The Semu people not only carried out the oppression of the common people, but also killed people at every turn, and treated the Han soldiers as slaves and beat and scolded them at every turn, and it was even more common to deduct food and wages. The Han soldiers in the city did not dare to be angry or speak out against the Semu people, but if the war was unfavorable or even the city was breached, the new annexed army would definitely not fight to the death, and might even fight back.

Hearing this, Tang Xiangwei and Liao Loach glanced at each other, and proposed to Ouyang Xuan that he would take someone to sneak into the city at night to plot against the soldiers of the new annex army, and open the east city gate to meet the outside world. Among the four gates of Chongqing Mansion City, the north gate has the largest number of troops because it is facing the Thunderbolt army, and the Semu people are also mostly in battle here, followed by the west gate, and the south gate and the east gate are the weakest. Ouyang Xuan immediately agreed to allow the two to sneak into the city, and decided to act according to the plan after dawn. In fact, although the Thunderbolt army only had four companies, it was not difficult to capture the big city guarded by 1,000 people, in addition to the lack of food and food in the city, and the low morale, but also because of the crushing advantage of gunpowder weapons over cold weapons. Ouyang Xuan agreed that Tang Xiangwei and Liao Loach ventured into the city, in addition to wanting to minimize the accidental injuries of the people in the city, they also wanted to reduce the consumption of ammunition. After all, "when the cannon goes off, the gold is ten thousand taels", and fighting a war is to burn money. Although Cao Ergou commanded the battle of Yongkang City and won a complete victory, he basically ran out of ammunition he carried, and was severely criticized by Ouyang Xuan. Due to the constraints of the gunpowder production capacity, the production of gunpowder in the Thunderbolt army has always been in short supply. Because in addition to gunpowder for military products, a large amount of gunpowder is also needed for mining and road construction.

The next morning it was still foggy. Under the instigation of Tang Xiangwei and Liao Loach, who infiltrated the city, more than 100 new annexed troops and Minzhuang took advantage of the fog to secretly go down the city to surrender to the Thunderbolt army. Under the cover of the fog, Ouyang Xuan sent Huang Dagen and his teaching company to ambush in the grass half a mile away from the east gate, preparing to rush in after Tang Xiangwei and Liao Loach opened the city gate. By noon, when the fog had finally lifted, the Thunderbolts launched an artillery bombardment. Cao Ergou, who was criticized for wasting ammunition, learned his lesson and no longer engaged in flowers on all sides, but concentrated fire on the city gate tower at the north gate. Because according to the intelligence of the Toucheng soldiers, the generals of the Semu people and most of their own soldiers were hiding inside, drinking wine while watching the new annexed army in the city.

After several rounds of shelling, a puff of smoke rose from the city, and the east gate slowly opened. The opening of the city gate made Huang Dagen, who was numb in the grass, overjoyed, he thought that Tang Xiangwei and Liao Loach had opened the city gate, and then ordered the teaching company to get up and rush to the city to meet Neiying. Unexpectedly, as soon as the teaching company rushed out of the grass, he heard the sound of horses' hooves in the direction of the city, and then dozens of horsemen rushed out of the city gate. This sudden change made Huang Dagen break out in a cold sweat, and he immediately ordered the soldiers to stop and prepare for battle. The Han soldiers of the Thunderbolt Army and the New Annexed Army did not have horses, and there were very few soldiers who could ride horses, and there was no doubt that these cavalry that rushed out were Mongols.

Huang Dagen's judgment was not wrong, these cavalry were the generals of the Semu people and their personal troops. The shelling of the Perak army caused chaos at the north gate, and the new annexed army and the people who had been temporarily captured to defend the city fled in all directions, and they could not be suppressed at all. Seeing that the shells continued to fall on the city gate tower, and a shell hit the city gate tower, killing and injuring several of his own soldiers, the general knew that the city could not be defended, so he simply "took the thirty-six plan as the best policy", so he ran away with his own soldiers. Among the four gates of Chongzhou Mansion, the west gate leads to Qiongzhou, the south gate leads to Xinjin and Jiangyuan County, the north gate leads to Yongkang and Hengyuan, and the east gate leads to Chengdu. The people of Semu fled from the east gate, and naturally fled to Chengdu.

The cavalry came very fast, and in an instant, they rushed to a stone's throw away from the teaching company, and Huang Dagen even saw the yellow hair of the colored cavalry rushing to the front, so anxious that he ordered to shoot and throw grenades. He knew that the infantry without formation could not withstand the impact of the cavalry at all, and Ouyang Xuan had repeatedly told the top brass of the Thunderbolt Army that without the obstruction of obstacles, even if the muskets and grenades were in the plains, they could not withstand the impact of the cavalry. To block the cavalry onslaught, only artillery and machine guns. It was simply impossible to produce a machine gun under the current technical conditions, and the teaching company did not carry a bulky artillery in this ambush, but only a newly developed musket. Fortunately, the grenades and unaimed muskets thrown by the Thunderbolts were not accurate, but the explosion was not small, and the horses were neighing. Seeing that someone was blocking the attack, he quickly turned the direction of the horse's head, bypassed the hastily formed array of the teaching company, and neighed all the way to the east.