Unlike most other Khitan generals who had limited knowledge of the Zhou army, especially the "Flying Dragon Army", as the leader of the younger generation of generals, Yelu Xianzhen once spent considerable effort studying his opponent with another equally outstanding young general, Yelu Xiugo. They not only conscientiously studied the letter written by Cao Jiyun, the general of Youzhou in those years, about the use of firearms by the "Shenji Army" of the Zhou State, but also tried the three flintlock muskets of the "Shenji Army" of the Later Zhou Dynasty that Xiao Siwen sent people to send to Linhuang Mansion in Shangjing before he was cut off by the "Youzhou Righteous Army" -- although the Khitan court also organized craftsmen to imitate this kind of firearm, but due to the poor quality of the steel, the imperfect gunpowder formula, and the primitive processing methods, the imitation samples were not too easy to explode. It's just that the weight is too large, and it is not suitable for actual combat use at all. In addition, these firearms in the hands of the "Shenji Army" are very different from the "Flying Dragon Army" in Beiping that they saw later, and they are not at the same level at all, and even if they can be imitated, they cannot be confronted with them, so the Khitan court finally gave up this unrealistic idea.

Moreover, Yelu Xianzhen and Yelu Xiuge also had a lot of exchanges with those Khitan generals and even ordinary soldiers who had fought with the former "Beiping Army", the current Great Zhou Forbidden Army, especially the "Flying Dragon Army", and learned a lot about the characteristics of the current Zhou army, especially the "Flying Dragon Army". Therefore, in a sense, Yelu Xianzhen and Yelu Xiuge can be regarded as the two people who know the Zhou army, especially the "Flying Dragon Army", the most knowledgeable among the Khitan generals and even the Khitan monarchs.

In Yelu's view, the advantage of firearms possessed by the Zhou army, especially the "Flying Dragon Army", could not be offset by virtue of the superiority in the city or its own numbers, not to mention that the current Liao army was actually at a disadvantage in terms of strength. In the face of the "Flying Dragon Army", which can give heavy damage to the opponent hundreds of steps away, and at the same time has the ability to destroy almost all strong cities, whether it is defending the city or fighting face-to-face, it is to use one's own shortcomings to confront the opponent's strengths, which is an out-and-out way to die. If you want to resist the Zhou army or win one or two battles in the confrontation between the two armies, the only way is to avoid the enemy's edge, take advantage of your own familiarity with the terrain, and seize the biggest shortcoming of the Zhou army, especially the "Flying Dragon Army", which is strictly dependent on logistics support, on the one hand, attract its main force with a part of its strength, and gradually consume its food, grass, weapons and ammunition; On the other hand, they sent a number of small units to attack and harass the logistics and supply lines of the Zhou army, making it difficult for the Zhou army to continue its grain and grass army, and making it fall into a situation of running out of ammunition and food. In this way, it is possible for the side to successfully delay or even block the pace of the Zhou army's attack, and then take advantage of the panic and anxiety caused by the Zhou army's running out of ammunition and food, and concentrate its forces to make a surprise attack on one of its parts, hurt it, and force it to stop the attack or even withdraw its troops.

Therefore, after leading the troops to leave Changchun Prefecture, Yelu Xianzhen did not rush to Fengzhou with reinforcements, but sent a partial general to lead 2,000 men and horses. First, it was to make a false impression that the imperial court intended to reinforce Fengzhou, so as to reassure the morale of the defenders there. Second, he summed up a series of methods to defend the city against the Zhou army, especially the "Flying Dragon Army", to inform the Fengzhou guard general and assassin Zhao Kuangfu, so that he could delay the Zhou army as long as possible and buy time for his own attack and assault. As for Yelu slanted himself, he led the main force of his troops and horses to hide and hide, ambush day and night, avoid the Zhou army coming from the front, secretly maneuvered between Wuzhou and Fengzhou, and divided into several small groups of soldiers and horses, preparing to carry out a comprehensive attack on the logistics supply line of the Zhou army.

On the tenth day of the fifth month of the lunar calendar in the seventh year of Jianlong (the twentieth year of the calendar), after completing the necessary grain and grass army accumulation, the Middle Route Army of the Northern Expedition of the Great Zhou Dynasty left Wuzhou and arrived at the city of Fengzhou.

Although compared to the Central Plains, Fengzhou City, which is only four miles in circumference, is not even as large as an inferior small county town. However, in line with the principle of leniency for the enemy, the generals of the Central Route Army still did not take it lightly. Therefore, while Cheng Fei, the deputy commander of the capital, commanded the army to set up camp, the two brothers Zeng Zhilin and Duyu Hou Mutel, the commander of the Central Route Army, took some of their personal guards to a small hill two or three hundred meters away from the south of Fengzhou City to observe the enemy situation.

The narrow city, the low walls, and the sparse and obviously absent-minded guards on the city's head did not attract Zeng Zhilin's attention in the slightest. At present, the only thing that makes Zeng Zhilin and Muttel feel a little tricky is the moat that surrounds the city.

Compared with Wuzhou, which is close to the Huang River (Xiliao River), Fengzhou City does not have a large amount of moat water due to water source problems. However, it is precisely because of the lack of water that the city was built to create a new realm, widening and deepening the moat to make up for this shortcoming.

For a nomadic people, fishing and hunting, it is rare to build such a city. Therefore, Zeng Zhilin, Mutel and others guessed that it was very likely that the person who designed the city was a Han or Bohai person. However, regardless of whether the founders of the city were Han, Bohai or Khitan, for Zeng, Mu and others, the difficulties were the same. The five-zhang (15 m) wide moat rendered the light steel bridge over the moat, which was only 10 meters long at the maximum, useless, and the deep moat, which was not deep but had an unusually muddy bottom, made it very difficult to climb from the bottom of the moat. In other words, the only way to get through the moat is to fill in the moat. Filling trenches means that artillery, especially medium and large-caliber artillery, cannot be used for long-distance fire support, and small-caliber mortars and infantry light weapons can only be used to suppress the city's head at close range, which usually means more casualties.

However, no matter whether there are difficulties or not, the battle must be fought and the attack must be attacked. Therefore, after returning to the camp from the city, Zeng Zhilin, Muttel and Cheng Fei studied the situation together and formulated a corresponding battle plan.

It is said that it is a battle plan, but in fact it can be summed up in a few sentences -- deterrent artillery bombardment, surrender and persuasion, (if you do not surrender) preliminary fire preparation, back soil filling, city-breaking artillery bombardment, infantry entering the city, and clearing up the remnants of the enemy.

Considering that after the camp was arranged, the time was approaching the end of the hour, and the sky was already getting dark, which was not conducive to their own actions. In addition, Fengzhou City is there, and its own army has already surrounded it, and it will not run away if it is too late to attack the city. Therefore, Zeng Zhilin and others decided to rest the army for one night and move again the next morning.

At the beginning of the eleventh day of the fifth month of the lunar calendar in the seventh year of Jianlong (the twentieth year of the calendar), nearly 200 artillery pieces of the artillery regiment of the Fourth Composite Infantry Division of the "Feilong Army" under the jurisdiction of the Middle Route Army, the artillery battalions of each regiment and the artillery battalion of the Second Independent Cavalry Regiment were placed outside the south gate of Fengzhou City; Behind them, more than 4,000 soldiers from the 1st and 2nd Battalions of the 10th Infantry Regiment of the 4th Composite Infantry Division of the "Flying Dragon Army" and the two infantry regiments of the "Security Army" will be ready to go; On either side of them, the 1st and 2nd Battalions of the Cavalry Regiment of the 4th Composite Infantry Division of the "Wyverns" and the 1st and 2nd Battalions of the 2nd Independent Cavalry Regiment waited for an opportune move, ready to surprise the defenders of the city to counterattack - even if such a counterattack was unlikely.

At the beginning of the day, with Zeng Zhilin's order, nearly two hundred artillery pieces roared at the same time, and fired two rounds of rapid fire at the southern city wall of Fengzhou City. In just ten seconds, nearly 400 shells were dropped to the left of the southern city wall of Fengzhou City. The nearly 500-meter city wall on the south side of Fengzhou City was completely shrouded in gunpowder smoke and flames, and the entire Fengzhou City trembled incessantly.