The Empress has abandoned me? I'll support a new emperor and destroy your kingdom!

The darkness before dawn is the deepest and most dangerous.

After a night of harrowing harassment and counter-harassment, Tiebiguan did not find true peace.

The torchlight on the city wall flickered in the cold wind, illuminating the weary but vigilant faces of the defenders.

The fires of the Di camp in the distance had dwindled, but the lingering killing intent seemed to cling to the city walls and surrounding areas, colder and more viscous than the night wind.

Yun Jin did not rest.

The news of the successful night raid and the chaos in Di's camp brought her and Zhou Bo a sigh of relief, but a deeper unease seeped into her body like ice water.

As Mr. Su once said, the closer we get to victory, the more frantic and unscrupulous the enemy becomes.

Modu Chanyu was no ordinary man; having suffered such a great loss, how could he possibly let it go? And was the area within the pass truly a unified entity?

During the day, she had already noticed some extremely subtle and illogical signs.

The team leader on duty at the East Gate had a shifty look in his eyes and hesitated slightly when answering questions.

The clerk in charge of collecting medicines at the wounded soldiers' camp wrote down ten extra doses of wound medicine, saying it was for backup, but he looked slightly flustered.

Even when Zhao Jianing secretly entered the city to replenish supplies, she seemed to catch a glimpse of a gaze quickly sweeping over the team from the shadows of the lookout post on the west city wall before disappearing just as fast.

These could all be illusions caused by excessive tension, or they could be... just the tip of an iceberg about to be revealed beneath the surface.

"Your Highness, you should rest." Qingdai brought in a bowl of freshly brewed calming soup that smelled of bitter medicine. Looking at Yun Jin's bloodshot but still sharp eyes, she advised him with heartache.

Yun Jin shook her head, took the medicine bowl, but did not drink it. Instead, she rubbed the rough rim of the bowl with her fingertips.

"Qingdai, go and call Yexiao over, and have him wait for me in the west wing. Also, please ask Commander Zhou to come over as well, and tell him that there is an urgent military matter to discuss."

"Yes." Qingdai didn't dare to ask any more questions and quickly withdrew.

Soon, Night Owl and Zhou Bo arrived almost simultaneously.

Zhou Bo's eyes were bloodshot, but he was in good spirits, clearly having also been up all night.

"Your Highness, what are your orders?" Zhou Bo asked, bowing respectfully.

Yun Jin dismissed everyone around her, leaving only Ye Xiao, Zhou Bo, and Qing Dai in the room.

She walked to the simple defense map of the Iron Wall Pass on the wall and traced a few dots with her finger.

"Commander Zhou, Night Owl. I'm uneasy." She cut to the chase, her voice low. "The Di people, having suffered a setback last night, may not dare to launch a full-scale attack on the city in the short term, but they will certainly not be resigned to their fate. Modu Chanyu is most adept at using deception, feigning an attack while secretly advancing. If a frontal assault fails, he will likely try to attack us from within."

Zhou Bo frowned: "Does Your Highness mean... there are still spies within the pass that haven't been completely eliminated?"

"It's not just possible, it's definitely possible, and the location is not low, it's extremely well hidden." Yun Jin said with certainty, "The assassination in Liuyin Lane and the destruction of the umbrella outside Yongding Gate both prove how deeply the other party has infiltrated the capital and the military."

Given the strategic importance of Tiebi Pass and its long history of management, it's unlikely that only a few small fry were caught before.

The truly powerful often remain hidden at the bottom, never revealing themselves until the very last moment.

Night Owl said in a deep voice, "I have indeed discovered a few suspicious points during my investigation over the past few days."

Liu Neng, the deputy commander of the East Gate, is a distant relative of the steward of a nobleman's mansion in the capital. He received a generous gift of unknown origin before the New Year.

Wang Lu, the military advisor in charge of some of the granary keys, had a concubine's brother who suddenly moved his entire family south half a month before the fall of Shuofeng City, in a hurry.

"And..." He paused, "One of the archers under Captain Han Lie of the Sharpshooter Battalion, while on his day off the other day, had a brief encounter with a suspicious peddler in the back alley of 'Drunken Immortal Residence' inside the pass. Although they did not speak, his eyes were strange."

Zhou Bo's expression grew increasingly grim. Liu Neng was someone he had personally promoted; Wang Lu had managed the granary for many years and was considered diligent; and Han Lie's men were the elite of the elite! If there truly was a traitor among them…

"We must not alert the enemy without solid evidence," Yun Jin said calmly. "But we must be prepared to lure them out and strike them dead in one fell swoop."

"Commander Zhou, the vanguard of Marquis Weiyuan's army, should arrive at Eagle's Beak Cliff, thirty li outside the pass, no later than the day after tomorrow. If you were Modu Chanyu, or a traitor within the pass colluding with him, when and how would you deliver the fatal blow to us?"

Zhou Bo's gaze sharpened as he followed Yun Jin's finger to the map, looking at the internal structure of Tiebi Pass, especially several water sources, granaries, armories, and... those sections of the city wall with hidden exits that were said to have been sealed off but could not necessarily be reopened.

"A coordinated attack from within and without, creating maximum chaos, to coordinate with the Di main force in a general offensive..." Zhou Bo gasped. "The best time is when the Marquis of Weiyuan's army is about to arrive, when the morale of the garrison inside the pass is at its lowest, and their anticipation is at its peak! That is... tomorrow night, or the early morning of the day after tomorrow!"

"Not bad." Yun Jin's eyes flashed with cold light. "The target is nothing more than poisoning, arson, opening the city gates, or a combination of these."

Night Owl, immediately send more men to conduct round-the-clock secret surveillance on Liu Neng, Wang Lu, and that sharpshooter under Han Lie, but under no circumstances should they be alerted.

At the same time, check the guards of all granaries, wells, and armories, especially the night shift schedule, to see if there are any unreasonable adjustments.

"Commander Zhou, under the pretext of strengthening defenses and welcoming Marquis Weiyuan, readjust the defenses of the four gates and key areas, but do not move Liu Neng and Wang Lu's positions, and even... you can appropriately create some 'favors' for them."

"Your Highness means..."

"Give them an opportunity, let them think they can take advantage of this." Yun Jin's tone was icy. "We need solid evidence, and we need to wipe them out at the crucial moment and expose the mastermind behind them! Qingdai, go and prepare some things immediately..."

She whispered a few instructions to Qingdai, whose face turned pale, but she nodded emphatically and hurriedly left.

"Night Owl, go to Commander Zhao's office in person and have him select one hundred of the most elite and reliable brothers to secretly ambush him after midnight tonight..." Yun Jin pointed to an area marked as an abandoned cellar on the map.

"Here, and near the two possible secret exits to the east and west. No movement is permitted without my order. Once the signal is given, spare as many prisoners as possible, especially the leader."

"yes!"

"Commander Zhou, tomorrow evening, under the pretext of discussing military affairs, summon Liu Neng, Wang Lu, and several other suspicious officers to the central military council hall. I will personally oversee the proceedings. At that time, command within the pass will be temporarily handled by your trusted deputy. Remember, make them believe that this is an excellent opportunity to strike."

"This subordinate understands!" Zhou Bo replied solemnly.

"Remember," Yun Jin concluded, her gaze sweeping over the two men, "this matter concerns the survival of Iron Wall Pass, the lives of countless soldiers in the Northern Frontier, and even more so... the dignity of the imperial court. You must be extremely cautious and strike with absolute certainty!"

……