Zhang Liao was not in Qian County, and it was Gao Shun who led the troops through Qian County. Although the heavy rain was heavy and the march was a little slow, the essence of the beginning of this war was the surprise attack of the Yan army on the Cao defenders...... Gao Shun marched thousands of miles in a zigzag half moon, in order to attack the enemy unprepared. The distance between the two sides is too close, you have me, I have you, there are spies everywhere on the battlefield in Yuzhou, and it is not easy to hide Cao's eyes and ears and let them treat the combat march as a regular transfer.

Heavy rain is the best cover, although Gao Shun only let the soldiers march at a slow speed on the official road in order to preserve his strength, and spend half a day every day to let his subordinates set up a camp that can shelter from the wind and rain to avoid the soldiers from contracting the wind and cold, but such weather is a problem for everyone. This is true for the Yan army, the Gao Shun department, and the Cao army, the Runan garrison, and the Cao envoys all over Yuzhou.

Everyone was stranded in this rainstorm, and Gao Shun, who had an extraordinary intention, could benefit from it, which was Zhang Liao's first thought about the battle in Runan.

The rainy season operation is a desperate move, but since it is an adventure, there is bound to be the possibility of obtaining huge benefits, and the interests that Zhang Liao wants in the eastern battlefield are to occupy all the three north-south arteries in the eastern part of Runan, so as to obtain the deterrent power of directly forcing Cao Cao's camp in Ruyin.

As long as Gao Shun nailed more than 10,000 soldiers and horses in the eastern part of Runan, there would be no suspense in this battle.

There are 30,000 Yan troops in the territory of Runan, all of whom are controlled by Gao Shun, except for the three elite battalions of his subordinates, and the rest of the soldiers and horses are the new soldiers recruited from Yanzhou in the spring and the divisions and Ji veterans who retreated from the Central Plains battlefield before.

The vast majority of people only have leather armor, leather bands, short swords, spears, and most of the long-range forces are also equipped with hard bows and light crossbows, all of which belong to the weapons abandoned by the main army of the Yan clan.

But this is also the backbone of the armies of the princes of the world.

Fortunately, Gao Shun still has 30 stone cannons, relying on 30 stone cannons to tackle key problems.

In the blink of an eye, between the marches and roads, the walled city that chokes the valley is in sight.

Gao Shun concentrated his forces and sent two sergeants from the lieutenant department to hold the two crossings in the middle and west of the road into Runan, and then waved most of his division to attack the Qianxi Valley, approaching Chengfu. Cheng's father's guard Li Dian received a message from Xiahoudun on the other side of the mountain half a day ago, but it was obviously too late to send troops to guard the valley...... On such a day, there is no one in the valley and there is still a danger of landslides and falling rocks, and it is difficult for the defenders to climb, so it is better to hold the city and wait for reinforcements than to go out of the city camp and be intercepted halfway.

Reinforcements, the father must need reinforcements. The strength of the Cao army died in the long war, and now there are only more than 20,000 soldiers and horses scattered in the whole county, and Li Dian's subordinates only have 4,000 soldiers, and they have no power to fight back when they go out of the city, but with the city, they can still fight.

Heavy rain will replace the sword to inflict an unbeatable blow on the enemy, and the city will be garrisoned for up to seven days, and if the father has not fallen, the enemy army will retreat due to cold and sickness. Even if they don't retreat, the defenders will have a fight.

But in the face of an enemy force nearly ten times larger, how easy is it to defend for seven days?

Reinforcements, at least another 3,000 reinforcements.

In the north of Chengfu City, Li Dian had set up three cities earlier, based on the towering mountain wall, and the thick wooden fortress was originally just a forward outpost, after all, the wooden fortress was the most afraid of fire attack, but the heavy rain on this day became an advantage for Li Dian, and immediately led the army to the north after receiving the news that Zhang Liao sent troops to attack south, and crossed the two cities one after another, and the soldiers and horses were in the lead.

There were two cities in the rear, one city, and only a few hundred people were stationed, and the people were recruited to distribute spears to speed up the exercises.

Li Dian knew very well that three simple wooden fortresses alone could not stop Zhang Liao, and now such a trapped beast was just delaying time, and even Li Dian himself did not know how long the three wooden fortresses could hold Zhang Liao's army, but he finally knew that he could resist the attack and defense of most of the Yan army's Chengfu City with small soldiers...... It's inevitable.

One hour after Cao's army entered Sanzhai, two thousand-man teams with galloping donkey carts and pack donkeys as the vanguard entered the valley, risked the rainy season to climb the mountain wall, scattered Wu Shi to guard all the dangers, and quickly set up a simple watchtower in the flat part of the valley with the wooden tools carried by the frame, forming a dense defensive net. Then, in less than half an hour, the two Yanzhou County National Soldiers Captains stationed in the valley and set up camp in the nearest place no more than fifteen miles away from Cao's Sanzhai, and there was a lot of construction next to it.

Like the carpenter camp of the Yuan clan in the past, they quickly built a walled wall in an hour by using the watchtower that had been erected earlier as an angle, quickly picking wood and soil. An hour is the time that Gao Shun carefully estimated.

Cao's troops from Sanzhai to this point, the cavalry attack only takes a moment, the foot soldiers travel quickly takes half an hour, and the front and rear exploration of the horse return takes another moment, and there is a moment of hesitation. If the Cao defenders took advantage of the Yan army's failure to set up a fortress and attacked here, this was just the right time for Gao Shun's front-line army to lay down a wall that was not strong to defend...... It only took another half an hour for reinforcements to arrive.

The fact is the same as Gao Shun's consideration, Li Dian, who was guarding the city, did not think of taking advantage of the Yan army to attack lightly for a while to boost the morale of the army, but the second time he sent a horse to return, the Yan army had already set up a watchtower in the front, and the few soldiers were not enough to take advantage, and the large soldiers were difficult to defend, which really made Li Dian hesitate for a moment. In this moment of hesitation, the third round of return Tanma had already sent back to the city the news that the two captains of the Yan army had entered the valley and started camping.

Missed opportunities.

In the torrential rain, the Yan army sent news back to the city one by one, laid down half of the wall, and stationed a school captain's department, in a very fast time, the Yan army had set up tens of thousands of soldiers and horses in the valley, Li Dian's heart to attack the camp was also scattered, and immediately ordered the sergeants to lay traps outside the city at the same time to delay the enemy's upcoming offensive.

Li Dian wanted to delay the Yan army's offensive as much as possible, he had three cities to take and throw to the Yan army, as long as he could fight and retreat in a few days, and finally hold Chengfu City before the reinforcements arrived. When the reinforcements arrive, there are tens of thousands of garrisons in Chengfu City, and they will have the confidence to drive away the Yan army.

It was not difficult for 10,000 defenders to defend the offensive of 30,000 enemy troops with the help of the city. Even if the Yan army had stone cannons every time they attacked the city, Li Dian was not worried about this. The stretching mountains outside Chengfu City can offset the advantage of the Yan Army's stone cannons to the greatest extent. Let alone...... He also has more than a dozen stone cannons erected on the northern urn city, destroying the enemy's stone cannons, dragging the war into winter, and freezing them to death if they can't kill the enemy!

The left and right Yan army must be more anxious than them!