Even if the Thunderbolt artillery is loaded with face kill shotguns, it is not easy to hit a high-speed target such as the cavalry. It's just that the secret man is bent on burning the grain, so that the 1,700 cavalry in his hands will pour out of the nest, and they will roam around the grain and grass camp and release arrows, and its density is really not low. In addition, Ouyang Xuan ordered the artillery not to aim at the cavalry, but to shell the area of 100 meters in front of the grain and grass camp, forming a circle of fire barrage, which made the Mongolian cavalry unable to rely on the camp at all, but lost a lot of men and horses. A small number of cavalry rushed to the edge of the camp to fire rockets between the shelling, but to no avail. A few rockets were quickly extinguished by the soldiers of the new annex who remained behind as soon as they hit the granary, and most of the rockets were extinguished by water on the ground as soon as they landed.

To say that the cavalry under the secret fire is indeed a first-class strong army, whether it is the Mongol tribe or the Han army, although it lost more than 200 cavalry after only two charges, it was not defeated under artillery fire. Just as they were about to charge for the third time, they were stopped by the secret one. Because a large number of warships came downstream, and these warships probably belonged to the Thunderbolts. Although it was the scorching heat of the July fire, the heart of the secret fire was like falling into an ice cellar. He had now understood that he had fallen into the preset game of the Thunderbolts. In this game, the Mongolian army was always led by the nose by the Thunderbolt army, and was weakened step by step. Now he finally found out that the Thunderbolt army had nothing in common with the traditional Song army, even if they didn't have a fortified city but only simple fortifications, they also had the power to fight with artillery, this Ouyang Xuan was too cunning! The strength of the Thunderbolt Army is too hidden! If he had known that they were deliberately showing weakness, he would never have attacked Hengyuan Fort, but followed Liu Heima's advice and built a castle for several miles around Hengyuan Fort, trapping it in the mountains. As for their naval army, as long as the supply of firearms in the mountains is cut off, it will not be difficult to deal with it. It's just that now, it's useless to regret it.

After thinking about it for a long time, the secret one already had the idea of retreating. If you want to say that it is useless, you will definitely lose face and even be ridiculed, but you can stop the loss in time. The 5,000 new annexed troops and 15,000 civilians he brought were all gone, and the cavalry that still had combat effectiveness under his command was only 1,500 people. If it is a field battle, the secret fire is confident that with these cavalry, the thunderbolt army will be completely annihilated, and even 10,000 Song troops will be defeated. It's just that these Thunderbolts will only be shrinking turtles, not giving him the opportunity to fight in the field at all, but constantly harvesting lives with artillery. Now that the grain and grass have been lost, it is appropriate to bring these cavalry back to Chengdu. If these cavalry suffered any further major losses, they would have to apologize to the Khan of Möngke for their crimes.

What made the secret man make up his mind to retreat was the battle situation of the three crossings of the water that followed. According to the messenger, the Perak sailors who attacked Sam Ferry were so heavy that they destroyed iron chains and a pontoon bridge, and the defenders had to sink several ferries full of stones in the river and cut down a large amount of wood and bamboo to block the channel, so that the Perak ships could not get any closer. It was only a matter of time before the Bolts were lost, and it only took half a day for the Thunderbolts to clear the obstacles and continue the attack. Moreover, it is believed that when he passed through the city of Chongqing, he found that the defenders were preparing to withdraw to Chengdu. The defenders, who were already in a state of panic after being shelled by the Perak warships, abandoned the city when they learned that the three crossings of the water were about to be cut off, fearing that their retreat would be cut off. The secret man was shocked when he heard the messenger's words, left a group of cavalry to set fire to the camp on the side of the mountain, and hurriedly retreated to the direction of Yongkang City with his men, preparing to cross the Jinma River in Daojiang County. It is about 100 miles from Yokohara Fort to Sandu Water, and if you go there at this time, it is estimated that the pontoon bridge has been cut off. The Mongolian army also has a pontoon bridge near the county seat of Daojiang, although the traffic volume is far less than that of the three crossings, but it is more than enough to pass more than 1,000 cavalry.

Seeing the sudden withdrawal of the Mongolian cavalry, Ouyang Xuan knew that Huang Dagen had already made a move on Sandushui as planned. It's just that he didn't send anyone to chase after him, and he didn't even send anyone to the cavalry camp on the side of the mountain. One is that the two-legged infantry can't catch up with the four-legged cavalry at all, and the other is that he is also afraid that the Mongol army will suddenly kill the horse pistol. The Thunderbolt army did not yet have the strength to fight in the field with the Mongolian army in the plains, and even if the whole army went together, it would not be able to stop the impact of the cavalry in the secret fire. At present, the most important thing is to digest the fruits of victory, in addition to screening and sheltering the surrendered new annexes and civilians, it is more important to transfer food to a safe place. These two things were much more important than the pursuit of the Mongol cavalry.

It is said that although Huang Dagen's battle was smooth on the side of Sandushui, it took a lot of effort to clean up the obstacles in the waterway. While the Perak army was busy cleaning up, the Mongol army and the new annexed army guarding the three crossings of the water fled completely, and even the Mongol cavalry stationed in Chongqing Fucheng fled to Chengdu through the two pontoon bridges that were still there. Of course, Huang Dagen did not find nothing, not only did they block back the 500 new annexed troops of Chongqing Mansion who tried to flee to Chengdu, but they also harvested a lot of grain and grass. Part of this grain and grass was the military supplies for the Mongolian army stationed in Sandu Shui, and the other part was temporarily stored here to prepare for transfer to the secret fire department. Of course, these grain and grass materials are not as good as the seizures of Hengyuan Fort, but they are much more than the grain and grass materials abandoned by the Mongolian army on the side of the mountain of Hengyuan Fort. When a fire broke out in the forest on the side of the mountain, Ouyang Xuan ordered someone to go and check it. Finding that the camp was empty, but there were still a lot of supplies, they sent them to extinguish the fire. Fortunately, the Mongolian army team that set the fire did not set fire to too many points in a hurry to escape, and the trees were lush and damp in summer, so they still grabbed about half of the grain, grass and other supplies.

After completely destroying the Sandu Water Pontoon Bridge, Huang Dagen led the warship to continue upstream. By the time he arrived in Daojiang County, he had already crossed the Jinma River from Daojiang County and fled to Chengdu. Huang Dagen was not annoyed by this, because the order given to him by Ouyang Xuan was to take Daojiang County and the Guankou Village upstream, and control the Jinma River. Ouyang Xuan's plan was to completely control the Minjiang River system above Xinjin City, control the territory of Qiongzhou, Chongqing Mansion and the former Yongkang Army, and then slowly plan the rest of the fertile land in the western Sichuan Plain. This area is fan-shaped, with the tall and steep Longmen Mountains in the west and north on the arc side, and the Jinma River in the east and the Nanhe River in the south on both sides, which converge at Xinjin City at the fan handle. In Ouyang Xuan's strategic planning, he only needed to control these two major rivers with the advantage of the naval army, and build castles in key river sections to build a defense system, so as to stifle the Mongol army's attempt to attack. In this system of river defense, Xinjin City is naturally the core, followed by Guan Kou Village and Pujiang City by the Pujiang River, a tributary of the Nanhe River. If the Mongols wanted to attack the Perak army, they only needed to cross the Jinma River from the east to reach the core of the Perak army, and if they wanted to attack the Perak army, they needed to cross the Min River, then cross the low mountains and hills of Meizhou under the control of Yu Xingbu, and then cross the Pujiang River and then reach Qiongzhou by land. This latter line of attack was a nightmare for the logistics of the Mongolian army. Therefore, the importance of Guankou Village is more important than that of Pujiang City, and the garrison here can not only prevent the Mongol army from crossing the Jinma River, but also block the connection between the Mongol army and the Tibetan area. Although Wei and Mao surrendered to the Mongol army, it was only because the local leaders of the Tibetan people pursued the "doctrine of doing great things", and whoever was strong would be attached to him in order to protect himself, and he would not die for the Mongols. In fact, in Ouyang Xuan's plan, the caravan of the Thunderbolt Army would also enter the two states to trade in order to obtain strategic resources.