In this realistic war game, only I understand the course of the battle.

When the granary caught fire, Shen Du was inspecting the cracks in the gate's sluice gate on the south gate tower. The crack, after several days of impacts, had extended from the bottom to the middle of the gate, with rust and iron filings falling with every gust of wind. He ran his finger along the crack, finding a tiny fork at its end—indicating the crack was widening and would completely collapse after a few more impacts. He stood up, about to ask Old Wei to find a blacksmith, when suddenly he heard a rapid gong sounding from the direction of the city center. It wasn't the city gate alarm gong—it was the granary's alarm gong.

He turned around. The sky in the direction of the granary was already tinged with a dark red light, and thick smoke billowed from behind the rammed earth walls in the city center, the column of smoke appearing particularly menacing in the night. His pupils contracted sharply. He handed the task of the heavy gate to his deputy and, leaning on his iron spear shaft, ran down the city walls. The old injury in his left leg ached as he ran, feeling as if someone was repeatedly cutting his knee with a dull knife, but he did not slow down.

The fire outside the granary was out of control. Several warehouses were ablaze simultaneously, flames leaping from the eaves and licking at the night sky, sparks whipped into the air by the heat like a swarm of fireflies. The soldiers guarding the granary were desperately dragging sacks of grain out of the fire; some were vomiting from the thick smoke, others were rolling on the ground, their armor on fire. Amu wasn't at the door. Shen Du rushed to the granary, grabbed a soldier fighting the fire, and asked him where Amu was. The soldier, his face covered in soot, shook his head and said he hadn't seen him. He grabbed another soldier, who also said he hadn't seen him.

"Old Wei!" Shen Du roared, "Send everyone out and search for Amu!"

Old Wei and his men searched the area around the granary thoroughly. They found Amu in a narrow alley behind the granary. Amu was sitting on the ground, leaning against a rammed earth wall scorching hot from the fire, his head bowed, his armor soaked in blood. He was still clutching the tattered account book in his hand, its pages fluttering in the wind, filled with dense records of each day's grain inflows and outflows. Beside him lay a short knife, its blade stained with blood.

Shen Du crouched down and pressed his fingers against Amu's neck. The pulse was weak, but still beating. He tore open Amu's armor to examine the wound—the cut was below Amu's left rib, angled upwards. It hadn't hit his heart, but it was deep, and blood was seeping out. He pressed his hand to the wound to try and stop the bleeding, and blood seeped through his fingers, soaking the account book that Amu always carried with him. Old Wei crouched beside him and handed him the water bag, his hands trembling—this veteran, who had fought his way back from Feishui, had almost dropped the water bag when he saw Amu lying on the ground.

"Who did it?" Old Wei's voice was hoarse and low, something flashing in his eyes in the firelight. Amu's lips moved slightly, uttering a very soft, almost imperceptible sound. Shen Du leaned down and put his ear close to Amu's mouth. Amu's voice was broken and intermittent, each word accompanied by a gasp: "Qiang spies...not just one group. There are more in the city. They've changed into the garrison's armor...mingling among the fleeing soldiers. Tonight...not just the granary...there are more..."

He didn't finish speaking. His hand loosened, the account book slipped from his fingers, and the pages scattered on the ground. This young man, who had walked all the way from Feishui to Chang'an, who had been carried across the cliff by Old Wei on the Xiaoshan plank road, and who had shared the last bit of leftover grain with everyone on the Hangu Pass city wall, leaned against the rammed earth wall with his eyes closed, a lingering thought on his lips. Shen Du grasped his hand, which was slowly growing cold. He lowered his head, and after a long while, he stood up, picked up the account book from the ground, dusted it off, and handed it to Old Wei.

"Investigate." His voice was calm, but Old Wei sensed something beneath the calm. "Investigate every single deserter who appeared near the granary tonight. Replace all the guards at the north and south gates with our own men. From now on, the city's password will change every hour. Anyone who doesn't match the password, regardless of their armor, will be detained. All the unburned grain in the granary will be moved to the drill ground west of the city. Old Wei, you will personally lead the guards. No one is allowed to approach."

Old Wei took the account book and nodded vigorously. He turned and took a few steps, then stopped and looked back at Shen Du—Shen Du was squatting beside Amu, using a short knife to cut the thin rope around Amu's neck that held the amulet. It was made for him by Amu's younger sister, Azhi, and brought from Chang'an. He had kept it hidden inside his armor during the retreat. The amulet was a small, tightly knotted red rope, blackened by Amu's sweat and blood. Shen Du put the amulet in his pocket and stood up.

"I need to go to the palace." He sheathed his dagger and said to the soldiers beside him, "This wasn't an accident tonight. They know the location of the granary, the changing of the guards, and Amu's daily routine of checking the grain reserves. They didn't act on a whim; someone in the city sent them a message. I need to know who that person is." He turned and walked towards the palace, the firelight flickering behind him, casting his shadow long and short on the rammed earth wall.

In the sparsely lit side hall of the imperial palace, Fu Jian sat behind his desk, draped in a worn fox fur coat. On the desk lay the city defense report that Shen Du had previously presented. His face was even thinner than before, and the wrinkles at the corners of his eyes appeared particularly deep in the candlelight. Shen Du knelt on one knee and briefly reported on the burning of the granary and the murder of Amu, then looked up into Fu Jian's eyes.

"Your Majesty, I request a search of the imperial palace." Fu Jian's finger stopped on the imperial desk.

"As I mentioned in my last report, there might still be Yao Chang's men among Your Majesty's guards. Tonight's operation was not a spur-of-the-moment decision—the timing, location, and method were all meticulously planned. There are no more than five people who can simultaneously grasp the granary shift changes and the movement of palace guards. I have already sent someone to secretly monitor one of them. Tonight, all the passwords at the city gates have been changed, and all the guards on the city walls have been rotated. No one is allowed to move without my order. Please allow me to investigate the inside man." Fu Jian was silent for a moment, then picked up a token from the corner of the table and placed it on the edge. "Investigate."

Shen Du took the token, took two steps back, and turned to leave the side hall. A cold wind blew in from outside, causing the candlelight to flicker violently. Fu Jian sat motionless in the shadows behind the candlelight, his hand resting on the imperial desk.

After leaving the palace, Shen Du didn't immediately begin the search. A search would alert the enemy; his priority was to first close the net—severing the connection between the city's spies and Yao Chang. He went to the north gate tower, summoned Commandant Zhu from behind the crenellations, and ordered him to immediately deploy plainclothes sentries inside the main city gates, keeping watch on anyone attempting to enter or leave. He then summoned Lao Wei to the south gate tower, instructing him to spread the news of the burned granaries—saying that the granaries were completely destroyed, and not a single grain of rice could be salvaged. This message didn't need to travel too far; reaching only the shacks near the city gates would suffice. Yao Chang had spies in those shacks, who would carry the news back to Weibei.

After arranging everything, Shen Du stood on the south gate tower and looked down. The Qiang camp outside the city was unusually quiet tonight; even the sound of patrolling horses' hooves was less frequent than usual. Yao Chang was waiting for his inside man to send a message. He didn't intend to wait any longer—whoever had leaked Amu's rules, this thorn in his side had to be removed before dawn.