With Xie Chang'an's help, Ye Jingchen stood on the mountain peak closest to the checkpoint.

This mountain is the lowest of the mountains, yet it is still three times as high as the checkpoint walls. The mountain is steep, with one side almost vertical.

The barren mountain is covered with stones, making it easy to find materials on the spot. At this altitude, stones are far more powerful than bows and arrows.

The guards of the Eastern Palace worked together to transport a windlass up to the top of the mountain from the less steep side. Then, they used the windlass to transport several catapults up the mountain from the steeper side.

Afterwards, Ye Jingchen ordered the Eastern Palace Guards to collect all the stones on the mountaintop.

After collecting all the stones, he ordered people to quarry and carve them.

This season is perfect for using the water-freezing-ice-cracking method to chisel stones.

During the day, the Donggong Guards were responsible for digging holes and filling them with water. At night, they would seal the holes so that the ice-cracked stones could be removed the next day.

In this way, enough stones were collected at the top of the mountain.

“This mountain is also a barrier for Tianji Pass. If the height of this mountain is reduced due to quarrying, wouldn’t Tianji Pass lose a natural barrier in the future?” Xie Shaoheng did not agree with this approach.

"General Xie, please rest assured. Killing the goose that lays the golden eggs is indeed unwise, but the Northern Barbarians will soon no longer pose a threat to the Great Abyss. Taking this one time will not cause any major problems," Ye Jingchen assured him.

In addition to the layout on the mountaintop, Ye Jingchen also ordered his soldiers to collect ice and snow, melt them into water, and then continuously pour the water out from the city walls.

The soldiers collected snow and ice from within a hundred miles of the pass. Apart from keeping drinking water, they also collected all other water sources and poured water out every day to freeze it into ice. Layer upon layer of ice formed on the mountains outside the pass.

As for the trenches at the foot of the mountain, before pouring water, he had many wooden sticks erected in the trenches. After watering, the wooden sticks froze into icicles. The icicles were so numerous that warhorses could not pass through them at all, and even people had to walk carefully in them.

"If we could also set up such a layout on the wasteland, wouldn't it stop the Northern Barbarians' iron cavalry from advancing beyond the wasteland?" When Xie Shaoheng saw the scene of ice pops standing in the trenches from the city wall, he immediately realized that this method could also be used on the wasteland.

Once the ice is thick enough, the Northern Barbarian cavalry will no longer be able to roam the wasteland.

"The wasteland is too vast; this method won't work." Ice pops can indeed stop iron cavalry, but if the ice pops aren't thick enough, they'll shatter at the slightest touch, rendering them meaningless.

The trench is low-lying, which is why it has this advantage.

After several days of preparation, the Northern Barbarian army finally appeared on the wasteland and attacked seven passes simultaneously.

This time, the Northern Barbarians openly attacked Yuheng Pass, but after launching only one attack at Yuheng Pass, half of their cavalry moved on to Tianji Pass.

Fifty thousand iron cavalrymen approached Tianji Pass, intending to break through it in one fell swoop, but when they arrived, they found that Tianji Pass had turned into an iceberg.

Before the siege ladders were used on the city walls, they were used to climb the mountain. However, the ice mountain was slippery, making it difficult to even walk, and they also had to face a rain of arrows and stones falling from the sky.

Ye Jingchen stood in the most conspicuous spot on the city wall, visible to all the Northern Barbarian soldiers, but they could not get close.

The siege began with great fanfare but ended in utter boredom. The northern barbarian generals discovered that, let alone breaching the pass, they would struggle to even reach the city walls alive.

Ye Jingchen also realized that he might have gone too far. Tianji Pass could not possibly be breached by tens of thousands of troops in a short time. If the generals of the Northern Barbarians were not stupid, they would definitely not linger at Tianji Pass.

As expected, upon discovering that Tianji Pass could not be breached, the Northern Barbarians decisively abandoned Ye Jingchen as bait, leaving several thousand iron cavalry to guard outside the pass, while the rest of their forces headed directly for Tianxuan Pass.

Ye Jingchen had previously planned to use the border defense camp to encircle and annihilate the Northern Barbarian Iron Cavalry, but now the Northern Barbarian Iron Cavalry has abandoned Tianji Pass, and the Divine Might Army of Tianji Pass is going to Tianxuan Pass to support the border defense camp instead.

Xie Shaoheng led 10,000 Shenwei soldiers to guard Tianji Pass, while Ye Jingchen led the remaining 20,000 troops to support Tianxuan Pass.

A few days ago, Xie Shaoheng would have been absolutely uneasy about letting Ye Jingchen lead so many Shenwei Army soldiers. However, setting up improved catapults on the high mountains and turning Tianji Pass into an iceberg were ideas that no ordinary person could come up with. Xie Shaoheng was completely convinced of his abilities.

All the soldiers at Tianji Pass were completely convinced of Ye Jingchen's abilities.

Some of them had been stationed in the northern frontier for over a decade and fought against the northern barbarians hundreds of times. This was the first time they had seen the northern barbarians helpless, which was truly gratifying.

The Northern Barbarian cavalry was known for its speed. By the time Ye Jingchen led 20,000 Divine Might troops to Tianxuan Pass, the 100,000 border guards defending the city were already showing signs of weakness.

Although they were both stationed in the northern frontier, they rarely faced the Northern Barbarian cavalry head-on. If they were suddenly attacked by the Northern Barbarian cavalry, they would be psychologically intimidated.

When Marquis Wu'an saw that it was Ye Jingchen leading troops to provide support, he was almost scared out of his wits.

If it weren't Ye Jingchen who came to their aid, even if they were temporarily outmatched and the Northern Barbarian cavalry entered the pass, as long as Xie Shaoling led his troops to support them, they would eventually be able to drive the Northern Barbarians out.

But now Ye Jingchen is the first to arrive. If anything happens to Ye Jingchen in the border camp, Marquis Wu'an dares not imagine how terrible the consequences would be.

Given how much the emperor values ​​his heir, he would certainly execute his entire family!

Ye Jingchen wanted to lead the Shenwei Army to the city wall to relieve the border guards, but Marquis Wu'an stopped him from going up.

He not only blocked the way himself, but also made the border defense battalion commanders join him in blocking the way.

A group of grown men were practically weeping as they tried to stop him.

"If you won't let me onto the city wall, then from this moment on, all the soldiers of Tianxuan Pass will be under Xie Chang'an's command." Ye Jingchen had considered this problem on his way here and had already thought of a solution.

Although he had studied under Zhenguo Gong for three years, he had never actually led a large army into battle. In terms of controlling the situation, he was certainly not as good as Xie Chang'an.

Therefore, it would be more appropriate for him to use his own safety as leverage to negotiate with Marquis Wu'an and the others, and let Xie Chang'an take control of the overall situation.

“Xie Chang’an is just a junior who has never been on the battlefield. How could he know how to command troops?” Marquis Wu’an naturally disagreed.

"Either Xie Chang'an goes, or I will go myself. The choice is yours!" Ye Jingchen said forcefully.

Marquis Wu'an scrutinized Xie Chang'an, a hint of barely perceptible disdain on his face. "Your Highness, I am the commander of this border defense camp. I must be responsible for the soldiers of the border defense camp. How can I entrust their lives to an unknown ordinary person?"

"He, an ordinary man, could render 50,000 Northern Barbarian cavalry helpless and force them to abandon Tianji Pass. Could General Li do the same?" Ye Jingchen retorted bluntly.

In this critical moment, he couldn't care less about respecting his teacher. Even if Marquis Wu'an had actually taught him, he wouldn't be polite, let alone if Marquis Wu'an was only nominally his Junior Guardian.