202 - Beneath the Sealed Passage

Three days after returning to Crossroads, Subin received approval to reopen the northern section of the abandoned mines. Commander Varik had agreed to provide six engineers familiar with the Underpass tunnels, while Ara arranged additional sensors and portable supports through the Crossroads Wardens. The expedition would not attempt to clear the entire northern passage. Its first objective was to remove the old barrier safely, inspect the chamber beyond it, and determine whether the underground structure could be reached without endangering the settlement.

Subin was pleased with the preparation. His previous expeditions had taught him that a powerful sword could solve many immediate problems, but it could not replace reliable information, sound construction, or people who understood the terrain. This time, the team had brought enough equipment to avoid improvising at every obstacle.

Yerin joined him at the western gate on the morning of their departure, carrying her spear and a compact pack of supplies. Jae-hyun and Liu Wei were already waiting beside Ara, who was checking the sensors one last time.

"Six engineers, four Wardens, and us," Jae-hyun said. "If this turns into another monster evacuation, at least we'll have enough people to carry the equipment out."

"You're assuming you'll be carrying equipment," Liu Wei replied. "I thought your specialty was complaining while other people work."

"I have many specialties. You only notice the ones that annoy you."

Subin continued toward the gate while the two argued behind him. Their familiar rivalry made the journey more comfortable, and it was a welcome change from the tense negotiations that had occupied most of the previous two days.

The expedition reached the Underpass settlement before noon. Varik met them near the northern mining gate, where the engineers had already secured the surrounding supports. The old passage had been closed for decades, but the recent survey had given them enough information to prepare a controlled opening.

"We've reinforced the hall and installed two emergency braces," Varik explained. "If the tunnel begins shifting, we'll withdraw and seal it again."

"Good," Subin replied. "No one moves beyond the first chamber until Ara confirms the conditions."

The group entered the abandoned mines with the engineers in front and the combat Awakeners covering the rear. They passed the old junction and crossed the underground river, reaching the Deep Survey Hall several hours later. The chamber looked exactly as they had left it, although the sensors placed near the northern barrier showed a slight increase in pressure.

Ara examined the readings. "It's still within safe limits, but the flow is building slowly."

"How slowly?" Varik asked.

"At this rate, it could take weeks to become dangerous. We have time to inspect the passage, provided we don't damage the channel."

The engineers began removing the metal braces one at a time. Subin watched the stone blocks as each support came free, ready to intervene if the structure shifted. After nearly an hour of careful work, the final block was moved aside, revealing a narrow opening filled with amber crystal growth.

The chamber beyond was larger than the sensor had indicated.

A broad cavern stretched beneath the mountains, its ceiling lost in darkness. Crystal deposits covered the walls, and a series of stone platforms descended toward a deep trench in the center. On the opposite side stood a massive structure built from black stone and pale metal, partially embedded in the rock. Unlike the abandoned mining equipment behind them, this construction showed little sign of erosion.

Ara stared at her readings.

"This isn't a mining complex."

Subin stepped through the opening, examining the structure across the cavern. "Can you identify it?"

"Not yet. But look at the platforms."

The platforms formed a descending route toward the trench, each connected by narrow stone bridges. Thin channels ran along their edges, carrying mana toward the black structure. The arrangement was deliberate, and the energy moved in a steady sequence from one platform to the next.

Varik approached the first platform cautiously.

"Our ancestors never described anything like this."

"Perhaps they never reached this chamber," Ara said. "The old records stop at the survey hall."

Subin followed the mana channels with his eyes. They converged at the far end of the cavern, where a broad opening had been cut into the structure's lower wall. Beyond it, the darkness appeared unusually dense, absorbing most of the light from the crystals.

Before they could approach, a sharp metallic sound rang through the cavern.

Everyone turned toward the trench.

A section of the nearest bridge had shifted several centimeters. Dust fell from its underside, and a thin crack spread across one of the supporting pillars. The mana flowing through the platform fluctuated, briefly brightening before returning to its previous intensity.

Ara checked her scanner. "The structure is drawing more energy than the channel can supply."

"Can we shut it down?" Yerin asked.

"I don't know what it does yet. Cutting the flow might destabilize the entire chamber."

Subin examined the damaged bridge. Its support had not broken completely; something beneath it was pulling the stone downward. He moved to the edge and looked into the trench, where pale crystals descended along the walls toward a faint blue glow far below.

A heavy impact sounded from the darkness.

The bridge shuddered again.

Varik ordered the engineers back toward the entrance while the combat team spread out along the platform. Subin remained near the damaged support, trying to determine whether the movement came from the structure or from something deeper in the trench.

Another impact followed, stronger than the first.

A section of the opposite wall broke apart.

Something climbed out.

The creature's front limbs gripped the rock with enormous hooked claws, dragging a heavily armored body over the ledge. It resembled a giant subterranean lizard, but its back was covered with overlapping plates of black crystal, and pale blue energy pulsed beneath its throat. Its hindquarters remained partly inside the trench as it surveyed the cavern.

The system identified it.

Abyssal Stone Reaver

Level 263

Rank: A+

The creature hauled itself onto the nearest platform, crushing the stone beneath its weight. Its head turned toward the mana channel, and the crystal plates along its back began glowing in sequence.

"It is feeding on the channel," Ara warned. "The structure is drawing energy, and the creature is trying to take it."

The Stone Reaver lunged toward the nearest platform junction. Its claws struck the channel, tearing away a section of pale metal and sending a burst of mana through the cavern. The resulting pressure wave knocked two engineers off balance, while the bridge beside Subin cracked from end to end.

Yerin drove her spear into the platform and used it to anchor herself as the shock passed. Jae-hyun and Liu Wei moved to intercept the creature before it could reach the central structure, but its armored tail swept across the platform and forced them to retreat.

Rafael planted his shield against the creature's next advance. The impact drove him backward several meters, and the shield's surface groaned under the force. He held long enough for Yerin to strike at the exposed joint behind its forelimb, forcing the Reaver to shift its weight and abandon the direct approach.

Subin had been watching its movement rather than its armor.

The creature wasn't simply attacking everything in sight. Each time the mana flow surged, it moved toward the brightest channel. When the flow weakened, it turned toward the trench, as if searching for another source of energy.

"Keep it away from the central structure," Subin called. "Don't waste attacks on its back plates. Target the joints when it turns."

The others adjusted immediately. Yerin drew the creature's attention toward the outer platform, while Jae-hyun and Liu Wei used coordinated strikes to force it away from the damaged channel. Rafael maintained the front line, absorbing the Reaver's heaviest blows without allowing it to reach the engineers.

Subin moved along the side of the platform, searching for a way to end the confrontation without collapsing the cavern. The creature's crystal armor was thick enough to resist ordinary cuts, but its movement exposed narrow gaps where the plates met. He could strike those openings, yet a reckless attack near the channel might release enough energy to destroy the bridge.

The Reaver suddenly changed direction.

Instead of pursuing Yerin, it drove its claws into the platform and tore a large section of stone free. The broken slab crashed into the channel, blocking the flow. Energy accumulated behind the obstruction, and the pale metal conduits began to glow with increasing intensity.

Ara shouted from the entrance. "The channel is backing up! We need to clear the blockage!"

Subin saw the problem immediately. If the obstruction remained, the structure would continue drawing energy into a system that could no longer release it. The resulting pressure could destroy the platforms and send everyone into the trench.

He moved toward the blocked junction as the Reaver turned to intercept him.

Subin drew Simple Edge and waited until the creature committed to its charge. At the last moment, he stepped outside the reach of its claws and cut through the narrow joint beneath its shoulder. The blade passed between the crystal plates, severing the flow of mana feeding its forelimb. The Reaver staggered, its charge veering away from the channel, and struck the platform with enough force to crack the stone beneath its chest.

Subin used the opening to reach the obstruction.

One precise cut separated the fallen slab from the conduit. A second removed the fractured metal that had trapped it. The accumulated energy surged through the reopened channel, flowing toward the central structure instead of bursting outward.

The change was immediate.

The platform stopped shaking, and the Reaver's glowing armor dimmed as the excess energy left the chamber. It tried to rise, but the damaged forelimb could no longer support its weight. Yerin and Rafael held their positions while Subin approached, keeping Simple Edge ready in case the creature attacked again.

The Stone Reaver lowered its head toward the channel.

Subin recognized the behavior from the other creatures they had encountered throughout the Great Passage. The Reaver had been drawn by the disrupted mana flow, and the struggle had become violent because the channel and the structure were competing for the same energy.

He stepped away from it.

"Give it room."

The team withdrew toward the outer platform. After several tense seconds, the Reaver pulled itself backward, descended into the trench, and disappeared into the darkness. Its retreat left the cavern damaged but intact.

Ara checked the readings while the engineers inspected the bridge supports. "The channel is stable again. Whatever this structure does, it is no longer drawing energy faster than the system can supply."

Subin looked toward the black-stone building. "Can we reach it safely?"

"Not yet. The bridge is damaged, and we need to understand the remaining channels before crossing."

The expedition spent the next two hours securing the platform and documenting the structure. Ara identified three major intake channels and one outlet descending toward the trench. The structure had been designed to regulate the flow through this section of the underground network, but its control mechanisms were buried beneath the lower platform.

They found no evidence that the structure had been built by the miners who once worked in the region. Its construction was far older, and the black stone matched materials used in several ancient installations discovered elsewhere in the World Dungeon. For now, however, its precise purpose remained uncertain.

Subin chose not to force entry.

They had reached the sealed passage, identified a functioning regulator, and confirmed that a powerful creature occupied the trench. Further exploration would require stronger supports, additional sensors, and a plan for reaching the lower platform without damaging the channel.

By evening, the expedition returned to the Underpass settlement with their findings. Varik agreed to keep the northern mines closed until the next survey, while Ara prepared a detailed report for Crossroads.

Subin reviewed the cavern map before leaving the settlement the following morning. The structure was no longer an unexplored mark on a survey plate; they now knew where its channels began, how they affected the surrounding mana flow, and what could happen if the system became obstructed.

The next expedition would be better prepared.

And this time, Subin intended to reach the lower platform without turning the entire cavern into a battlefield.