The first tentative attack was frustrated, and Qin Qiong had to retreat the army. Cheng Yaojin jumped straight and insisted on going to the hot balloon to check the terrain of the Marundu City in person. No matter who persuaded him, it was useless. Qin Qiong was not good at suppressing him as the main general, so he had to agree in the end. As a result, Cheng Yaojin really got on the hot balloon and flew into the sky. Of course, there were ropes tied under the hot balloon for reconnaissance to prevent the balloon from being blown to other places.

Cheng Yaojin flew to the sky to observe the city of Wandu. Qin Qiong was not idle either. He kept urging the mountain to transport the equipment used for siege up. However, the mountain road was not wide at first, and it was difficult to transport from bottom to top. In addition, the equipment used for siege was also very heavy, so the transportation speed was not satisfactory.

Originally, Li Xiu thought Cheng Yaojin would come down soon after he went up. After all, although he could see clearly in the sky, he could only observe the general situation in the city at most to make a reference when siege in the future. But what he didn't expect was that Cheng Yaojin stayed for nearly an hour after going up. Finally, he estimated that the fuel on the top was used up, so he sent a signal to slowly fall. The people below also pulled a rope to prevent the hot balloon from falling to other places. It would be bad if it fell into the Marun Capital.

"Shubao, I thought of a solution!" As soon as the hot balloon landed, Cheng Yaojin jumped out of the hanging basket excitedly, then grabbed Qin Qiong's arm and shouted.

"What's the solution?" Qin Qiong was stunned when he saw Cheng Yaojin's excited look, and then he couldn't help but ask.

"We can't explain it clearly for a while, so let's find a place to discuss in detail!" Cheng Yaojin said excitedly at this time, and then pulled Qin Qiong down the mountain. The place on the mountain was too small and could not even be able to support the tent, so the army was divided into several parts and had to go to the domestic city at the foot of the mountain when resting.

Cheng Yaojin took Qin Qiong and Li Xiu down the mountain together, and then came to his room excitedly, without rushing to say what he thought. Instead, he took the paper and pen and started drawing. Although Cheng Yaojin's painting skills were terrible, Li Xiu and Qin Qiong soon realized that Cheng Yaojin was painting the general structure diagram of the Wandu City.

After waiting for a while, Cheng Yaojin threw down his brush and said with a smile: "Come on, come and see, this is the general terrain of Marudu City. Although I didn't draw well, I have drawn some important places!"

Li Xiu and Qin Qiong also came over to watch it. They saw that the shape of Marudu City was round in front and pointed at the back, but there were many strange protrusions in the middle, which looked like an egg with thorns. I don’t know if it was the shape of Marudu City, or whether it was the deformation of Cheng Yaojin’s paintings. However, it doesn’t matter. The key is some important information marked on Marudu City.

The main gate leading to the mountain is the south gate of Marutou City, which is also the main gate. The defense of this gate is the most tight. In addition to this gate, Marutou City has two other gates, which are in the northeast and southwest. However, the gate in the northeast is very small, and it is also a water gate. Because there are two water sources in Marutou City, it finally converges into a river. This river flows out from this gate in the northeast. There are iron gates on the water gate, which are impossible to enter and exit.

In contrast, the city gate in the southwest looks much more normal, and as long as you go around from the south, you can see a large area of ​​relatively flat open space in front of the gate in the southwest, which looks very suitable for attack. If you are a person who is generally unknown, you will definitely abandon the difficult main gate and attack from the city gate in the southwest.

However, if the Tang army really attacked from the southwest city gate, it would just fall into the trap of the Goguryeo people, because the southwest city gate looked easy to fight, but behind the city gate there was a large-scale urn.

The so-called urn city is like its name, like a water jar, surrounded by city walls. As long as the enemy rushed in through the city gate, and then closed the city gate, and the arrows above the head were like rain, the enemy would be like a mouse entering the water jar, and in the end they could only die without life. It can be said to be very vicious. Of course, when the Goguryeo built this urn city, they probably wouldn't have dreamed that one day the enemy could fly to the sky to observe the situation in the city.

"Since you have observed, we can only attack from the main gate. After all, compared with the other two city gates, although the main gate is dangerous, it is at least better than that city." Qin Qiong could not help but show a contemplative expression after hearing Cheng Yaojin's account of Maru Capital.

The northeast is the Water Gate and the iron gate. At the same time, there will definitely be heavy troops. It is difficult for the Tang army to approach, and the southwest urn is also very troublesome. The difficulty of attacking is even higher than the main gate they tested today.

"Yes, although this main gate seems dangerous, it is actually not impossible to crack. Through the temptation just now, we can see that the reason why the main gate is difficult to fight is that in addition to the terrain, the most important thing is that there are two peaks on both sides of the front gate. There are fortresses on the peaks and hidden soldiers inside. In this way, the fortresses on the two peaks form a horn with the defenders on the gate. If one attacks, it will inevitably encounter the attack of the other two." Cheng Yaojin gave a detailed explanation of the situation of the main gate.

"I know all of these, but what's the use of saying these? Do you have a way to conquer those two fortresses?" Qin Qiong asked with a frown at this time. He also knew that the two fortresses outside the main gate were the key, but he couldn't think of any good way to conquer them for a while.

"Hehe, I really thought of one. When I was observing the hot balloon just now, I found that the two peaks outside the main gate were too steep and there was no way to climb around and the city wall could not be built on the mountain. So the Goguryeo people built a suspended bridge between the city wall and the mountain. The materials and troops they usually needed also needed a suspended bridge for transportation. As long as we destroyed these two suspended bridges, the Goguryeo people would definitely not be able to repair them in a short time. Then it will be our chance!" Cheng Yaojin finally explained his method at this time.

"Hanging Bridge?" Li Xiu couldn't help but show a surprised expression when he heard Cheng Yaojin's words. He hadn't noticed it before, but looking at the map drawn by Cheng Yaojin, it was hanging on the back of the mountain. Standing in front of the city gate, it was impossible to see it at all, so naturally I didn't find this problem. Of course, I'm afraid that the Goguryeo people who designed Maruto would not have thought that someone would fly to the sky to observe the situation in the city.

"But this suspended bridge is on the back of the mountain, and it is so high that we can't reach it if we want to destroy it, unless you can fly..." Qin Qiong didn't react at first, and frowned and said to himself, but when he was halfway through, he immediately realized that Tang Jun can really fly to the sky now, but he, a veteran, sometimes ignores this advantage.

"Hehe, although our hot balloons are mainly used for observation and information, they can also be used for attack at some critical moments. For example, in the Battle of Weishui, the hot balloon made great contributions. It is said that a thrown grenade almost killed Jie Li." Cheng Yaojin also grinned at this time. If possible, he really wanted to try the feeling of throwing grenades from the hot balloon down.

"Since it is a suspended bridge, it should be covered with wooden boards on the iron chain. In this case, it is best not to use gunpowder to destroy such a bridge, but to use tinder oil to make the effect better!" Li Xiu also spoke at this time and suggested that sometimes there are always more solutions than problems. No matter what kind of problem, there will always be solutions in the end.

"Okay, let's try tomorrow. I'll ask someone to prepare tinea oil!" Qin Qiong said without hesitation. As long as the connection between the two peaks and the city wall was destroyed, with the size of the two fortresses, there would probably not be much material storage. As long as the Tang army worked harder, they should be able to attack the city gate. Then they would use gunpowder to blow up the city gate. Then, that would be the death of Quangai Suwen and his son.

Li Xiu was also very excited at this time. He also began to study the detailed steps of using hot steam balloons to destroy the suspended bridge. The first problem to be solved is the determination after the hot steam balloons are launched. If there is no artificial control, the hot steam balloon will only float with the wind. Therefore, the best way is to use a rope to pull it like when observing the information today, so the way to control the hot steam balloons to reach the sky above the suspended bridge, and it is also convenient for continuous attack.

However, the load capacity of a hot steam balloon is limited, but if multiple hot steam balloons are lifted off, it is easy to collide in the air, which is too dangerous. Moreover, the turbulent oil on the hot steam balloon must be replenished after use. This time must be as short as possible, otherwise the Goguryeo people will have time to put out the fire and even lay the bridge again.

The above details seem to be small, but in fact they are related to the success or failure of destroying the suspension bridge tomorrow, and also to the ability to break through the Maru Capital. Therefore, Li Xiu also calmed down and made a detailed plan. Finally, he discussed with Qin Qiong and Cheng Yaojin, and then summoned craftsmen to make some modifications to the hot balloon to adapt to tomorrow's attack.

That night, Li Xiu had almost no eyes for a night, and the craftsmen in the army were also busy all night under his command. They waited until the morning of the next day that they were finally ready. However, what Li Xiu and the others did not expect was that there was a sudden blow today, and the wind was not small. In this weather, it was not only dangerous to take off the hot balloon, but also difficult to control the direction. In the end, they could only discuss it with Qin Qiong and postpone the plan.

But even Li Xiu didn't expect that the wind would last for several days, and it was the north wind. Even if their hot balloons rose to the sky, they would not float to the Marundu City. This made everyone very helpless. Moreover, with the north wind, the weather became colder and colder, especially the temperature in the mountains changed greatly. They might sweat heavily during the day, but at night, it was biting cold wind, and even snow fell on some mountains.
Chapter completed!