The Great Wall—
It was the cornerstone of every ancient dynasty's survival.
For the agrarian civilization of the Central Plains, its greatest threat had always been the fierce nomadic tribes of the grasslands.
Before the Wall was built, barbarian cavalry raids happened almost every year.
These horsemen traveled in small, fast-moving groups. They would loot and kill, then vanish before reinforcements could arrive. There was nothing anyone could do.
That changed once the Great Wall rose—its endless stone spine halting the thunder of hooves.
For the nomads to plunder now, the cost became enormous.
They either had to storm fortified passes or climb mountains on foot.
The first option required stacking up corpses to breach the walls. The second meant even if they stole goods, they'd die being chased down without horses.
Forced by necessity, the scattered grassland tribes began to unite.
Eventually, several powerful alliances formed, combining strength to face the Central Plains.
Contrary to common belief, the Great Wall wasn't a waste of manpower or money.
In fact, it saved vast amounts of defense spending.
When Chen Sanshi once read the Records of the Great Sheng Dynasty, it mentioned that during the Kaiyuan Era, an official had presented a cost analysis to the emperor.
The calculations were complicated, but the conclusion was clear—building the Great Wall saved ten times more silver than it would have cost to permanently station large garrisons for border defense.
The Poyang region was mountainous and steep.
Cavalry and large formations could only move within about 200 li, and the Great Wall perfectly covered that range.
Heading north from the Thousand-Household Division, Chen Sanshi didn't travel far before a colossal, serpent-like structure appeared before his eyes.
"Hundred-Household Chen, thank you for taking over," said Zhao Kang as he gave instructions. "Ten days from now, Hundred-Household Feng's unit will relieve you. You'll rest then."
From now on, three Hundred-Households would take turns guarding the Great Wall watch posts.
Over one hundred soldiers began their rotation.
Chen Sanshi rode his White Swan horse, inspecting the length of the wall.
When the handover was done, he climbed the steep stone stairs to the top.
The Great Wall stood around seven meters tall, with a base width of six meters and a top width of about five to six meters.
Every ten li, a beacon tower stood guard, each manned by five soldiers.
That meant the entire 200-li stretch was just right for a Hundred-Household's manpower.
At first glance, one hundred men over that distance sounded too few. But in truth, it was more than enough.
The Great Wall's primary purpose wasn't to block every soldier—it was to stop warhorses, slow enemy advances, and deliver intelligence.
Once danger was spotted, they would ignite the beacons immediately.
Smoke would rise, and within the time of half a stick of incense, the Thousand-Household Division at Poyang would mobilize its full forces.
Besides, this wasn't an active war zone.
Barbarian tribes outside this sector were few and scattered—overall, it was considered secure.
Since this was the first day, Zhao Kang stayed behind at each beacon tower, leaving veteran soldiers to pass on their experience—how to watch for movement, how to interpret signals, and how to properly use the beacon system.
A beacon fire wasn't simply about lighting flames.
It was a complete communication system.
There were four beacon components—Feng, Biao, Ju, and Xin—each corresponding to a different signal form: fire, light, smoke, and flag markers. Combined in various ways, they could relay detailed messages.
For example, they could signal exactly how many enemies were coming, or from which direction.
Reading about it in books and seeing it in action were two completely different things.
"Ten days," Chen Sanshi muttered to himself. "We'll be stationed here for ten straight days."
As a commander, he had to set an example—no slacking.
But that didn't mean he'd waste time.
At each watchtower, soldiers rotated their shifts.
So at night, Chen Sanshi would stay awake keeping watch. During the day, he rode back to the camp's apothecary to help out and learn.
He only slept three to four hours a day, relying on the focus and vitality granted by his Reading skill to hold himself together.
After ten days, nearly all of the 300 taels Sun Li had given him were gone.
Yet combined with the effects of the spiritual grain, his cultivation progress soared—he was close to mastering the tempering bone stage!
[Technique: Undying Golden Serpent Spear (Upper Scroll) (Beginner)]
[Progress: 410/500]
"All this, and I still can't purge the spiritual grain's toxin fast enough," he thought. "If I had real combat, I could advance even faster."
Still, there was no need to worry about suspicion.
He'd already done his research—among the Eight Great Garrisons, at least two men had achieved this kind of rapid progress.
And the first among them was none other than the Grand Commander, Sun.
The second person was the Grand Commander Sun's third son—now deceased.
There were definitely others like him in the capital as well.
So in truth, Chen Sanshi's cultivation speed, while shocking, still fell within the range of "genius."
And since others mistook him for someone possessing the Nine-Dragon Body, his rapid progress was perfectly explainable.
There was no need to waste effort hiding his true realm for now.
"Clang!"
Chen Sanshi exhaled deeply and lowered the long spear in his hands.
Another long night of watch duty had passed.
The eastern sky was already glowing pale white.
He stood atop the wall, gazing toward the distant horizon.
The past ten days had been unusually peaceful.
Not a single figure had appeared on the grasslands.
He actually wished a small band of cavalry would come raiding—enough to give him real combat to temper his spear skills and help him absorb the energy from the spiritual grain.
But such things couldn't be forced.
At least all that relentless training had paid off—his medical skill was now on the verge of entering the beginner stage, and he could rely on tonics to keep strengthening himself.
At the hour of Mao (5 a.m.), Hundred-Household Feng arrived on schedule to take over the watch.
Chen Sanshi mounted his White Swan horse and returned to camp with his men.
Recently, all the constant riding between the wall and the camp, along with the daily care he gave his horse, had steadily improved his Horsemanship technique.
[Skill: Horsemanship (Beginner)]
[Progress: 150/200]
He couldn't help but wonder—since horses were just mounts, how far could this skill possibly go?
Back at the garrison, Chen Sanshi headed straight for the apothecary—only to spot a familiar face near the camp entrance.
Wang Zhi had just returned from visiting his family in the prefectural city.
"Shitou!"
Wang Zhi grinned, flashing his teeth as he approached. "How've you been lately? I mean, the officer sent for the Elite Selection—who came?"
"The Grand Commander's own daughter and son."
Chen Sanshi dismounted and added casually, "By the way, Miss Sun was asking about you."
"They…"
Wang Zhi's expression stiffened as he tested the waters. "What did they say?"
"Miss Sun said she doesn't know you. Hundred-Household Wang, did you change your name or something?"
Chen Sanshi raised a brow. "You asked me to speak on your behalf, but at least tell me what crime you committed first."
"I…"
Wang Zhi looked visibly uncomfortable, forcing a bitter smile. "Shitou, forget it. I changed my mind. You don't need to speak for me anymore. And if you ever meet the Grand Commander, don't mention me. Just say you picked up the cultivation manual on the street."
With that, he turned and hurried off as if fleeing for his life.
"...?"
Chen Sanshi stood there, baffled.
What was he so terrified of?
Was he really that scared of Sun Li and her brother?
If Wang Zhi had truly committed some grave crime, how was he still alive and serving here?
It didn't make sense.
Unable to figure it out, Chen Sanshi simply shook his head and made his way to the apothecary.
"Hundred-Household Chen, you really never take a break," said Medical Officer Jiang in surprise.
This young man was relentless—almost frighteningly so.
"Can't afford to rest," Chen Sanshi replied with a grin.
He moved around the room skillfully, sorting herbs and refilling decoction pots for the martial officers.
With his perfect memory, every herb that passed through his hands—its nature, effects, and properties—was instantly engraved in his mind.
Every tonic brewed in the apothecary, he memorized completely—down to the ingredients, dosage, and heating times.
At last, a flicker of light shimmered across his inner panel.
[Skill: Medicine (Mortal) (Beginner)]
[Progress: 0/500]
[Effect: Mastery of Medical Theory; Recognition of Formulas Upon Sight]
[Recognition of Formulas: For all mortal-grade medicines—upon sight, the formula shall be revealed.]