Although there were few Liao defenders left at the head of Gu'an City at this time, the Hou Zhou army that was besieging the city did not blindly attack, but stopped after advancing in an orderly manner to a place about three hundred steps away from the southern wall of Gu'an City, and rearranged into a formation. In the middle of the military formation, the ballista artillerymen, under the cover of the infantry around them and the rangers on both wings of the military formation, began to adjust the ballista carts they pushed all the way. Among them, some of the ballistas were aimed at the section of the city wall that had been damaged by artillery, and the other part was aimed at the head of the city and the city gate, ready to attack the Liao army who were defending the city at any time, or the enemy cavalry who wanted to rush out of the city gate.

At the same time, the remnants of the defenders on the city who were stunned by the shelling just now also gradually came to their senses, and they saw that the Zhou army under the city had approached to the point that it was only two or three hundred steps away from the city wall, and they were still arranging some strange instruments, so they didn't care about the pain on their bodies, and ran down the city wall with a rolling belt, and went to report to Cao Jiyun, who was still waiting for the news in the cave of the hidden soldiers--of course, the people who went to report the news were those who were still sane, and the other soldiers who had been frightened by the fierce artillery fire were delirious and almost crazy. I couldn't move, so I was left to kowtow to all the gods in the sky and beg for God's blessing.

However, the soldiers who ran down to the city to report the news soon realized that they had come at the wrong time. Their commander, Cao Jiyun, didn't bother to listen to their report now. Although there had been an artillery bombardment a few days earlier, the small-scale artillery bombardment of the demonstrative style was a world of difference from the large-scale, sustained shelling of the "Divine Machine Army" just now. The shock of the shelling just now to Cao Jiyun was too great, so that he could not recover from this extreme shock for a while. Moreover, unlike those defenders who stayed at the head of the city to monitor the Zhou army, Cao Jiyun, as the defender of a city, had far more things to consider than ordinary soldiers. Therefore, when the defenders of the city who were directly hit by artillery fire recovered from extreme panic, Cao Jiyun was still thinking about the countermeasures for an artillery attack of that scale, so naturally he couldn't listen to the report of the defenders.

However, to Cao Jiyun's disappointment, in the face of such a powerful attack force, as the side that defended it, he did not have any way to effectively deal with the artillery. The only condition that can effectively weaken the power of the Zhou army's firearms is actually the weather, and the letter he wrote to his boss Xiao Siwen asking for help mentioned that in the case of bad weather, especially rainy days, sending cavalry to carry out a surprise attack on the enemy army while the enemy's artillery is not finished, is probably the best choice that can effectively weaken the power of the Zhou army's firearms. And to realize such an assumption, in addition to needing God to be very face-saving and a few more heavy rains, the only way to pray for his boss Xiao Siwen to lead the main force of the Youyun Liao army to Gu'an as soon as possible, and take the opportunity of the small number of the other party to solve the vanguard of the Zhou army in front of him. But. In order to realize his vision, the prerequisite is that Gu'an City cannot be lost. So, after making up his mind to defend Gu'an City until reinforcements arrived, Cao Jiyun's mind also returned to a sober state. After listening to the defenders of the city who reported the news repeating the situation under the city, he immediately made a judgment - the enemy's attack on the city head with firearms was not over, but he was afraid that there were still powerful moves to show in the siege battle later. Therefore, after only a little thought, he ordered the Liao army to send another 180 people to the city to monitor as before, and the main force still took refuge in the hidden soldier cave until the Zhou army's infantry began to attack the city.

Facts have proved that Cao Jiyun's decision is very correct. Just when the Liao army of Yidu had just rearranged in place at the head of the city, the second round of firepower strikes of the Hou Zhou army under the city arrived. Unlike the first artillery attack, which covered the city's head in full, this time the ballista attack was mainly focused on the section of the city wall that had been damaged by artillery.

As the commander of the ballista battalion waved the command flag in his hand violently, the siege powder cartridges were thrown out by the strong catapult force of the ballistas, and deeply penetrated into the exposed rammed earth wall of the damaged city wall, and a violent explosion occurred a moment later, increasing the damage to the city wall little by little, in order to completely collapse this section of the city wall that was already somewhat crumbling as quickly as possible. At the same time of focusing on bombarding the city wall, some ballistae also threw gunpowder bags weighing several catties and embedded with various sharp things on the city, which disrupted the speed of the Liao army to restore the city defense, and created favorable conditions for the battle to be launched soon - although the accuracy of the ballista's close-range attack is not much higher than that of the artillery long-distance shooting, because it can maneuver with the siege infantry, and there is no possibility of accidentally injuring the siege infantry between the artillery position and Gu'an City, so it was arranged to act with the siege infantry. Provide the latter with the necessary fire support. ,

Although the siege powder cartridge was filled with only black powder, its explosion had limited destructive power. However, in the face of the continuous blows of dozens or hundreds of siege powder cartridges, the already badly damaged section of the city wall was finally overwhelmed, and collapsed in the exclamation of the Liao army defending the city and the cheers of the Zhou army after the siege, turning into a gentle slope that could be smoothly entered and exited. Seeing this scene, Xu Shao'an, who had already been unable to stay in the back, and came to the command of the siege troops with his own personal guards, immediately ordered the siege troops to immediately carry out the next attack according to Jihua, and must not give the defenders a chance to repair the gap.

With Xu Shao'an's order, the thousands of foot soldiers who participated in the siege immediately took action, except for a small number of people who were left to guard the crossbow artillery, most of the rest of the foot soldiers immediately began to push all kinds of siege equipment to Gu'an City and continue to move. As the foot soldiers approached the city wall, the ballista threw gunpowder packs at the city head until the foot soldiers were only a few dozen paces away from the moat. And as the ballistas stopped firing, the responsibility for covering the fire naturally fell to the flintlock musketeers and crossbowmen—while the other infantry began to fill the moat with the help of the chariots, three thousand flintlock musketeers and fifteen hundred crossbowmen stood ready to destroy the enemy forces who dared to stop the infantry from filling the moat.

When the infantry of the Later Zhou army began to move in the direction of the city wall, Cao Jiyun also received a report from his subordinates that the Later Zhou army had stopped the artillery attack on the city head and the city wall was blown up.

Hearing that the city wall had been knocked down for a while, Cao Jiyun couldn't help but be shocked. On the one hand, he ordered the Liao army, which had been hiding in the cave for more than an hour, to immediately enter the city, and fight back against the attack of the Zhou army's foot soldiers with all his might, and never let the other party break through to the city. On the one hand, he sent his cronies to the young and strong people in the city under the city to take soil to make sand bags, and carried them to the collapse of the city wall, intending to re-plug the gap.

The main force of the Liao army defending the city rushed to the head of the city, immediately entered the battle, and began to attack the Later Zhou soldiers who were filling the moat with strong bows and crossbows, and fired rockets to ignite and destroy the Zhou army's chariots. Seeing the main force of the Gu'an defenders and the young people in the city, they wanted to stop their own attack and block the city wall that had been blown up. Later, the Zhou army's flintlock pikemen and crossbowmen immediately fired back, suppressing the Liao army at the head of the city, and blocking and shooting at the young men who tried to re-plug the gap in the city wall. For a time, the southern city wall of Gu'an City was filled with gunsmoke, and the sound of killing shook the sky.