The attack method formulated by An Qingxu and Cui Qianyou was as follows. While conducting feint attacks with thousands of people in the direction of the east gate and north gate, they would use a wave of attack teams with a size of 10,000 people in the direction of the south gate without interruption. The army launched an attack on Tongguan City.

While ordering the sergeants to cross the forbidden ditch and climb to the west edge in preparation for climbing the city, they ordered tens of thousands of sergeants to transport rocks and soil, as well as cut trees and bamboos, and fill them together outside the south gate on the east side of the forbidden ditch, which is the narrowest. At that section, we plan to fill up this forbidden ditch and turn the natural danger into a thoroughfare again.

An Qingxu's confidence in making such a decision came from the fact that he had 150,000 troops under his command, and the arrival of nearly 200,000 troops led by his father An Lushan, who was only two days away. Judging from the situation during the daytime attack, it was estimated that there were at most only 150,000 troops in the city. There are more than ten thousand Tang troops, but their combat effectiveness is not strong. If they attack the city overnight, and take advantage of the dark night on top of the city that the Tang troops cannot see clearly, it will provide them with a convenient opportunity to fill up the Forbidden ditch and fill up a section of the Forbidden ditch while attacking the city. Then. After filling up a section of the forbidden ditch, we will increase the intensity of the attack and be sure to capture Tongguan City.

After An Qingxu's order was issued, the rebel attack began immediately. The first 10,000 troops descended from the east edge of the Forbidden ditch into the Forbidden ditch in a continuous manner, tried their best to climb to the west edge of the Forbidden ditch, and then used ladders to After arriving at the city, the sergeants who supported the operations and were responsible for filling the forbidden trench also began to fill the forbidden trench with sacks of soil, stones and large sections of wood and bamboo.

However, after the attack began, An Qingxu and Cui Qianyou, who were commanding the operation, discovered that the situation was abnormal.

The average distance between the east edge of the forbidden ditch and the city wall of Tongguan South Gate is 80 steps, which is about 120 meters. It is basically within the range of the Tang army's arrows at the city head and the Twelve City beacon towers. The rebels have been expected. Yang Xi, who knew how to transport earth and fill up the forbidden ditch while attacking the city, ordered the sergeants on the city top to attack the attacking troops in a wave of 4,000 people when the rebels began to attack the forbidden ditch. The rebels launched intensive shooting.

Of course, the bed crossbow on the top of the city also started shooting continuously.

After finding out that the rebels were preparing to attack the city overnight, Dou Hua and Zhang Jian's 8,000 troops, who had received a short rest and replenished food and water, were also ordered by Yang Xi to replenish all of them to the South Gate city head. In this way, the direction of the South Gate The defensive strength of the city was nearly 16,000, which doubled the original number of personnel. The number of sergeants shooting in each wave also doubled, and the number of arrows flying from the top of the city naturally doubled. .

The number of sergeants on the beacon towers of the twelve consecutive cities has also been increased to 300 per city!

"Report to the general, the Tang army's arrows on the city top are very dense, and our army has suffered heavy casualties!" A sergeant ran up to a Zhonglang general who was commanding the siege and reported the situation in a panic, " The reinforcements from the Tang Army seem to have arrived, and the city is full of people!"

"I know, let's investigate again!" The general named Wu frowned and angrily ordered the sergeant who came to report to inquire about the situation again. After the sergeant ran away quickly, he immediately called the sergeant on standby, "Quickly Report the attack situation to His Royal Highness the Crown Prince and Deputy Commander Cui. Reinforcements from the Tang Army have arrived. The arrows on the city top are denser than during the day. Our army has suffered heavy losses!"

"Yes, General!" The sergeant on standby immediately ran away and reported the situation to An Qingxu and Cui Qianyou who were watching the battle on the hill behind.

"What? The Tang army's reinforcements have arrived at Tongguan?" An Qingxu was shocked when he heard the sergeant reporting the battle situation and the situation of the Tang army at the top of the city.

In fact, he had already sensed something strange from the shouts of the Tang Army on the top of the city and the unusual sound of war drums. He was already guessing whether the subsequent Tang Army had arrived at Tongguan, but he did not expect that he had guessed right.

"Have the reinforcements of the Tang Army really arrived at Tongguan?" Cui Qianyou was also surprised.

Judging from the fighting situation in the afternoon, the Tang Army did not arrive at Tongguan, but the situation now seems to be different from that in the afternoon. The formation of the Tang Army on the city wall seems to have also changed, and the arrows shot down are more dense than during the day. The shouts became louder. If this was not a bluff by the Tang Army, it must have been the arrival of follow-up reinforcements from the Tang Army.

But neither An Qingxu nor Cui Qianyou was sure whether the Tang army's reinforcements had really arrived.

They didn't want this to happen. If the follow-up troops of the Tang Army really arrived at Tongguan, then the battle would be impossible to fight. The natural danger of Forbidden Valley would reappear, and even if all their troops were to charge desperately, they would not be able to reach the top of Tongguan City.

Because of doubts, An Qingxu did not issue new orders, and the charge and filling of the forbidden ditch continued.

Under the intensive arrow fire from the Tang army at the city head, a large number of charging sergeants fell on the edge of the forbidden ditch or in the forbidden ditch. A large number of sergeants who were preparing to transport mud to fill the ditch were also shot down on the east side of the forbidden ditch. The soil they transported could not be filled. Go into the ditch. For a time, the east edge of the forbidden ditch was filled with corpses. Countless injured people lay there moaning and shouting in pain, hoping to get help from their companions, but in exchange they were ignored by their companions, and even trampled by them.

The number of rebel sergeants who were shot at the east edge of the Forbidden ditch was so large that the sergeants who followed up the charge were greatly disturbed.

There were also many corpses and injured people falling into the Forbidden ditch. The large section of the Forbidden ditch that had been washed away began to be filled with corpses again.

The average height of the city wall of Tongguan City is about four to five feet, about thirteen or four meters. In addition to the height difference of the terrain, it is at least seven to eight feet and almost twenty meters higher than the east edge of Forbidden Valley. It is ten feet higher than the city wall. The beacon towers in Erlian City were nearly ten feet higher than the east edge of the Forbidden ditch, and thirty or forty meters higher than the bottom of the Forbidden ditch. Because they were attacking against the height of the terrain, the rebels stood near the east edge of the Forbidden ditch and fired volleys. , it is possible to shoot to the city wall, but the strength is already weak. It is difficult to shoot to the beacon towers of the Twelve Liancheng City, unless there are super powerful generals like Wang Sili and Pang Zhong.

The rebel sergeants who rushed to the bottom of the forbidden ditch were unable to shoot their arrows so high. It can be said that the rebels had to charge hard despite the rain of arrows, and the casualties on both sides were completely disproportionate.

"Reporting to His Highness the Crown Prince, the Tang army's arrows were very dense and more than 2,000 people were injured or killed, but no one broke through the Forbidden ditch!"

The sergeant's report again made An Qingxu feel even more uneasy. He was absolutely sure that the Tang Army's follow-up reinforcements had arrived at Tongguan. He also knew that with the arrival of the Tang Army's reinforcements, the effect of their night attack would no longer be as expected. After thinking painfully for a while, An Qingxu made a decision that he couldn't even figure out whether it was wise or foolish.

"Pass this order from the Crown Prince and the whole army will stop attacking!"

It is very difficult to go up and down the forbidden ditch in the dark. Even when there is sufficient light during the day, you have to be careful, otherwise you will easily fall. The difficulty increases exponentially at night. Many soldiers who were lucky enough to escape the arrows were injured by their feet when they went down into the forbidden ditch. If they stepped on the air, they would roll down directly, and many people would be killed or injured. The reinforcements of the Tang army had already arrived, and under the intense fire of arrows from the top of the city, the mud-carrying sergeants could not even reach the edge of the forbidden ditch.
Chapter completed!