In the middle of the night, Xiaoxiao was sleeping soundly with her arms wrapped around He Yunxiao's. He Yunxiao estimated that it was about time, so he pried her little hands off and got up to relieve her.

"Master, let me do it. You can get some rest."

Qing Yuzi didn't stand on ceremony with He Yunxiao. After all, staying up late would cause dark circles under her eyes, and she was already quite worried about her appearance, so she couldn't be careless now.

Although He Yunxiao was on night watch, he was not idle; he was secretly pondering the matter of Luoyue Pass.

While sending a letter to Mengbao and Li Xiangjun might indeed resolve the Qi army's heavy casualties during the siege, the distance to Yan was vast, and the letter could be delayed in various places. This single letter would take at least a month to travel back and forth. What if the King of the Northwest led his army to attack the city before then?

The best method is still to find a way to break through the Moon Gate without relying on a Grandmaster.

But that's easier said than done. Luoyue Pass isn't known as the number one pass in Qi for nothing. It's not going to be so easy to break through.

As He Yunxiao was thinking, he suddenly remembered that when he was trying to win over Sister Jiang, the system gave him an item called "Sand of Luoyue Pass". He hadn't researched it yet. Could it be a powerful item similar to the Yan Kingdom's border defense map?

He Yunxiao summoned the system and selected the item. Sure enough, this system was a freeloader. It said it would "gift items", but in reality, you still had to get, steal, buy, or rob the items yourself. The system just gave you a location!

He Yunxiao cursed and opened the location, only to find that "the sands of Luoyue Pass" were located a hundred miles to his east, and that location was the Suyab City he was heading to.

...

On the evening of the following day, He Yunxiao and his group arrived in Suyab City without incident.

This is a small town, but like all the cities in the Northwest, even though it is small, its city walls are high and thick, ready to defend against enemy attacks at any time.

With Li Jin's travel permit, He Yunxiao wouldn't have much trouble getting into this small town.

After entering the city, he first found an inn and settled the female characters in, then went to the location located by the system.

It's getting late, and even if we go to Tingfeng Tower to send a letter, we'll have to wait for the scouts to set off tomorrow, so there's no rush.

The reason for not taking the female leads along was mainly because Fei Bao and Xiao Xiao weren't very compatible, and Fei Bao might not want to go shopping with He Yunxiao and Xiao Xiao. Taking either Xiao Xiao or Fei Bao alone would inevitably make the other feel neglected. Therefore, He Yunxiao simply decided to go alone.

With multiple female leads, it becomes especially important to treat them all equally.

Of course, this depends on the specific circumstances of each female lead. Some female leads cannot be treated equally, such as Ruobao, Chuchu, and Mengbao.

Beautiful women attract a lot of trouble; there's nothing you can do about it.

He Yunxiao followed the system's location and walked through Suyab City.

This city was originally built to serve the trade route between Qi and Yan, but now that Qi and Yan are at war, business in the city is quite sluggish. The taverns are empty, and there aren't many people on the streets.

Fortunately, the war hasn't been going on for very long, and the taverns and shops are still holding on.

It is conceivable that if Qi and Yan continue fighting for a long time without negotiating peace, this small town will inevitably perish along with the decline of trade routes.

The system located He Yunxiao in a dilapidated house.

This courtyard is dilapidated and desolate, long abandoned. The wooden doors are rotten, the bricks and stones are cracked, and wild grass grows rampant.

He Yunxiao knew no one was home, but he still pretended to knock on the door.

Is anyone there?

"Sorry to bother you."

After asking for permission, He Yunxiao used his light-footed skill to leap over the courtyard wall and into the courtyard.

The courtyard was quite ordinary, feeling like a dilapidated house, and had nothing to do with anything high-end like "system items".

He Yunxiao stared intently at the system's location and found that the location was indeed there.

Having no other choice, He Yunxiao could only wander around the courtyard, looking for anything unusual.

After wandering around for a while, He Yunxiao didn't find anything unusual in the courtyard. The only thing worth mentioning was the well in the courtyard.

This place is not comparable to Yinjing; the land here is barren and arid, and any family with a well must be a wealthy one.

The wooden well pulley was no longer usable, so He Yunxiao had to take a stone and throw it into the well. He could faintly hear the splashing sound of the water hitting the well.

There is water in the well.

Actually, there's no need to be so sure. Just look at the lush weeds in the yard and the relatively moist soil outside to get a glimpse of what's going on.

The land outside Suyab is arid like sand, but the land here is cool and slightly damp. This must be thanks to this well.

He Yunxiao stared at the handful of damp earth in his hand, looking at the system's location, and suddenly felt that there was a reason for this, and the system would not make baseless accusations.

Why is the system giving me hints about the soil here?

Water? Soil? Dampness?

This place is so arid, where does the water come from?

He Yunxiao suddenly remembered when he first came to this world, Yang Zhe was competing with him in poetry. Yang Zhe was from Hexi County, which is a local. The first line of Yang Zhe's poem was "Riding a horse north of Xiaoshan, I heard the song and returned at sunset".

Nitrate Mountain.

Nitrate is a white mineral salt.

Xiaoshan is not a mineral salt mountain, but rather a mountain that symbolizes "white".

The most likely source of white on the mountain is not minerals, but snow!

Snow is water!

He Yunxiao's mind raced. His intuition, honed by years of reading, became exceptionally sharp. The Qi Kingdom, a fictional world, couldn't have appeared out of thin air; it must have been designed by the author based on real-world alterations.

According to the logic of the real world, this corresponds to the "ancient Western Regions" in the real world! Of course, it is currently a northwestern province.

In this northwestern province, there is a massive water conservancy project, a testament to the wisdom of the working people: the karez system. This system utilizes meltwater from high-altitude glaciers and snowmelt.

Simply put, it involves using groundwater for agricultural irrigation!

He Yunxiao smiled as he looked at the well in the courtyard.

The area around Luoyue Pass may not be as arid as it appears.

Meltwater from the glaciers and snow on the mountaintop has likely created a considerable amount of groundwater over thousands of years.

What does water mean in arid regions?

The source of life, the prosperity of agriculture, and the killing flood.

In ancient times, Bai Qi flooded Yan City. If the Qi army could find underground water today, it would be no problem to breach Luoyue Pass with a flood in no time.

However, this was too cruel. He Yunxiao planned to tell Ruobao this plan to resist the Southwest King's strategy of forcibly attacking the city, with the aim of postponing the attack and delaying it until the Qi-Yan peace talks. With peace talks, they could be confident of peacefully retaking Luoyue Pass.

He Yunxiao breathed a sigh of relief after discovering the secret of the groundwater. Now he had a delaying tactic; he just had to wait for news from Mengbao and Li Xiangjun.

Regardless, the plan to launch a full-scale attack on Luoyue Pass is most likely doomed to failure.

The discovery of groundwater could also be used to improve the lives of people on the border after the war.

He Yunxiao is now feeling refreshed and energetic; doing a good deed definitely makes a difference.

He skipped out of the courtyard and strolled briskly through the streets of Suyab, hoping to buy Xiaoxiao some candied hawthorns. Unfortunately, Suyab didn't have such a luxury as snacks.

Normally, He Yunxiao would have complained, but he was in a good mood and hummed a song all the way back to the restaurant.