Too many female prisoners, a special forces soldier transmigrates and marries wildly.

"What I mean is, it's possible that someone has cleared the blockage, or even... secretly changed the route. But I can lead people to try to clear it and bring in unpolluted fresh water from outside the city. It's just that the project is quite large and requires manpower and resources," Old Official Chen said, bowing his head.

Lin Feng pondered for a moment: "Alright, you are in full charge of this matter. You may mobilize some auxiliary soldiers and craftsmen, who will be under your command. Construction will begin in three days."

Old official Chen, moved to tears, accepted the order and left.

"Han Tao," Lin Feng turned around, his gaze sharp, "send your capable men to keep a close eye on everyone related to water affairs, especially Old Chen and his family and cronies. See if anyone makes any unusual moves or tries to pass messages out."

"Second, send Lei Bao to the storeroom to count how many intact water bags and leather pouches we have left. Secretly fill them all with purified water and scatter them in various hidden troop caves and key locations within the city walls, in case of emergency. This matter must be kept secret and carried out by our own brothers."

Han Tao's eyes lit up: "The commander is trying to... lure 'Mountain Ghost' and the people behind him into thinking we're overwhelmed and lower our guard, so they might even attack again?"

"Not only do we need to lure them into attacking, but we also need to make them believe that we've run out of clean water and that morale is about to collapse." A cold glint flashed in Lin Feng's eyes. "Then, when they think they've succeeded and jump out, we'll wipe them all out in one fell swoop!"

"Understood! This subordinate will make the arrangements immediately!" Han Tao's spirits lifted, and he accepted the order and left.

The next evening, the sky was overcast. Yan Qing quietly came to the study to report.

"Guards, there's been some movement. Old Chen's grandson, this afternoon, under the pretext of visiting relatives outside the city, was 'routinely checked' by our men at the city gate, and we found this in the lining of his shoe." Yan Qing handed over a small roll of paper wrapped in oiled paper.

Lin Feng unfolded the document, revealing several lines of small writing in extremely fine charcoal: "The water poison has taken effect, and the army's morale is wavering. Lin relies heavily on his troops, but the water supply is running low. We can proceed with the second plan: three days from now at midnight, at the southeast corner tower. 'Mountain Ghost'."

The note was unsigned, but its meaning was clear: "Mountain Ghost" reported to his accomplices outside the city that the poison had taken effect, Lin Feng was relying on Old Chen, but the clean water was about to run out. He instructed his accomplices to follow the second plan and take action at midnight three days later at the southeast corner tower.

"Southeast corner tower..." Lin Feng's gaze fell on the map.

The southeast corner tower is located at a relatively remote corner of the city wall. However, a section of the wall beneath it has been slightly weakened by rain erosion in the past, making it one of the few areas in the city that requires significant reinforcement. If it were to be breached from the inside at this time, or if an enemy were to climb over it…

"What about Old Chen?" Lin Feng asked.

"As instructed by the garrison commander, we only kept a secret watch and did not alert him. He was still 'assisting' in organizing the waterway maps at the government office today, but he spent half an hour alone in the archives in the afternoon. Our men went in to check later and found that the old drawings of the underground canals and city wall structures near the southeast corner tower had been disturbed," Yan Qing said.

It really was him! "Mountain Spirit" was none other than Old Chen, the seemingly honest and kind official who had lived in Iron Wall City for generations!

He knew the city's waterways and canals intimately, and may even have been involved in part of the city wall's construction. To tamper with things secretly would have been incredibly easy for him. The fact that Feng Kun could bribe such a person shows that his ambitions were far from small.

"Very good." Lin Feng tapped his fingers lightly on the table. "Three days from midnight... It seems they are planning to coordinate from the inside and outside, making trouble at the southeast corner tower. Yan Qing, you continue to keep a close eye on Old Chen and see who he has been in contact with these past few days, especially... whether he has tried to obtain gunpowder or digging tools."

"yes!"

Midnight, starless and moonless, the cold wind biting to the bone.

Near the southeast corner tower, torches were sparse, shadows flickered, and the clanging sounds of digging and shouts carried far into the quiet night.

Old Chen, wrapped in a thick fur coat and holding blueprints, was directing dozens of "soldiers" and craftsmen as they "struggled" to clear a section of culvert blocked by silt. The guards on the nearby city walls also seemed to be fewer than usual.

It is almost midnight.

Taking advantage of the opportunity to check the progress, Old Chen quietly slipped into the shadows at the base of the city wall, took out a tinderbox from his pocket, gently lit it, and drew three circles in the darkness outside the city.

A moment later, a faint light appeared in the withered grass about a hundred paces outside the city, responding to the three flashes of light.

Old Chen grinned maliciously and strode back to the "construction site," giving a wink to several of his trusted craftsmen.

The men understood and slowly moved to a pile of wood near the entrance of the culvert that appeared to be randomly piled up but actually contained gunpowder and caltrops. They then took out their flint and steel.

Once the signal is given outside the city, the gunpowder will be ignited to blast open the entrance to the underground channel, and the barbed wire hidden in the wood will be detonated to create chaos.

Meanwhile, in the darkness outside the city, hundreds of elite Di Rong soldiers, with gags in their mouths and cloth-wrapped hooves, silently lay in ambush at their designated positions, waiting for the explosion to start their surprise attack and pour into the city through the breach!

Time ticked by, minute by minute. Old Chen's palms were sweating as he stared intently at the city gates.

Suddenly, on the southeast corner tower, a lantern that had been extinguished by the wind blazed up and hung high, standing out conspicuously in the darkness!

This wasn't the agreed-upon signal light! Old Chen's heart skipped a beat.

Immediately afterwards, the "soldiers" and "craftsmen" who were "digging hard" around suddenly stopped what they were doing, turned around, drew their swords, nocked their bows, and their cold eyes instantly locked onto the dozen or so people led by Chen Laoli!

Torches suddenly increased in number, illuminating the area as bright as day!

"Old Chen, it's late and cold, thank you for your hard work."

Lin Feng's voice rang out from the shadows of the corner tower. He walked out slowly, dressed in light armor with a long sword at his waist. His eyes were like lightning as they fell on the ashen-faced old official Chen.

"Clearing the underground channels is a pretense; your true intention is to coordinate an inside attack, blow up the city walls, and lure the Di barbarians into the city, isn't it, Lord 'Mountain Spirit'?"

Old Chen trembled violently, the tinderbox in his hand falling to the ground with a clatter. He looked up abruptly, his eyes filled with disbelief and horror, and hissed, "You...you knew all along?!"

"I knew when I found the secret letter in the sole of your grandson's shoe," Lin Feng said calmly.

"Oh, by the way, the Di Rong ambush troops outside the city..." He pointed to the spot where the firelight was responding outside the city, "are probably being 'warmly received' by Han Tao and Lei Bao right now."

As if to confirm his words, a deafening battle cry, the dense vibration of bowstrings, and the panicked roars of the Di Rong people suddenly rang out from the southeast direction outside the city!

Suddenly, a burst of firelight appeared, clearly indicating that the ambushing Yan army had already launched their attack!

"No—!" Old Chen let out a desperate howl, suddenly pulled a dagger from his pocket, and stabbed it into his heart!