The drainage tunnel was longer than Lincoln had expected.
After walking for about ten minutes, the tunnel’s direction remained unchanged, heading straight north.
Section by section, the concrete cylinder stretched forward in the flashlight’s beam.
Cast joints appeared every few meters, seeping water that dripped into the drainage channel along the bottom.
The footsteps of the three echoed far down the tunnel, blending with the dripping water to form a monotonous beat.
There was no lighting of any kind inside the tunnel.
It was a functional conduit of the drainage system, built without any lights.
The group’s range of vision depended entirely on how far their flashlights could reach.
Lincoln kept his eyes on his feet.
The water in the channel flowed north, shallow enough to stay below their boot soles and clear enough to see the bottom.
So far, there were no leeches.
Flowing water was not suitable for them to cling to; this judgment had been correct.
Still, he did not lower his guard.
Because the iron door behind them was only shut, not locked.
If there were enough leeches, they would squeeze through the gaps in the door.
And the drainage tunnel sloped downward to the north, meaning the water flowed in the same direction they were traveling.
Once a massive swarm of leeches poured into the upper reaches of the tunnel, they could drift down with the current, moving much faster than crawling on the ground.
Lincoln kept this possibility in mind and quickened his pace.
After another five minutes, he noticed the water level beneath his feet changing.
Earlier, it had been a mere film.
Now, the water reached their ankles.
The current was also speeding up.
This was abnormal.
The water volume in a drainage system should remain stable, not show such a stark change in a short time.
Unless someone upstream had opened a valve, or a massive amount of water had been injected into the drainage system.
Lincoln paused and glanced back at the tunnel behind him.
He shone his flashlight back; the cylindrical tunnel stretched into the darkness beyond the reach of the beam.
But he saw the change on the water’s surface.
There were ripples on the water in the distance.
These weren’t natural ripples from the current, but waves caused by things moving in the water—dense, tiny ripples surging toward them from the depths of the tunnel.
They were moving fast.
Lincoln stared at the ripples for two seconds, then turned back.
“Move faster.”
Their pace quickened from a fast walk to a jog.
Boots splashed through the deepening water, soaking their pant legs.
The water level was still rising, now reaching mid-calf.
As Lincoln ran, he swept his flashlight forward, finally spotting a change about twenty meters ahead.
The tunnel widened there.
Not abruptly, but gradually transitioning into a larger space.
The cylindrical concrete walls expanded outward to both sides, and the ceiling rose.
The valve room.
A relay junction of the drainage system, used to control flow direction and volume.
The three ran into the valve room.
The room was much larger than the tunnel, about six or seven meters wide and over ten meters long.
The ceiling, over three meters high, was webbed with large-bore cast-iron pipes and red manual valve wheels.
The fluorescent lamps overhead were lit.
The main power of the Training School had been restored earlier, and even this functional room deep underground now had electricity.
The light wasn’t bright, but it was far better than relying on flashlights in the tunnel.
A recessed sump channel ran straight through the center of the floor, filled with half a meter of water.
There were two exits on the north wall of the room.
The one on the left connected to another section of drainage tunnel, a cylindrical concrete pipe identical to the one they had come from.
The one on the right was smaller, with a label above the doorframe: “Maintenance Access Corridor • North Exit.”
“To the right.”
“The maintenance access corridor should lead to the surface.”
Just as Lincoln took two steps, he heard a sound.
It didn’t come from behind them, nor was it the rustling sound of leeches crawling.
It was a familiar humming.
A low male voice, slowly humming a wordless melody.
It was exactly the same as the one they had heard in the corridor on the third floor of the Training School.
The sound echoed from the pipes on the ceiling of the valve room, resonating within the cast-iron walls and causing the entire room to hum softly.
Rebecca’s face went pale instantly.
Billy raised his P226 immediately, but he couldn’t find a target.
Lincoln’s gaze swept across the room, but he saw no human silhouette.
However, he noticed a change on the water’s surface in the sump channel.
Dense black figures surged from the water.
A massive swarm of leeches boiled up from the bottom of the channel, their density so high that the water turned pitch black within seconds.
They were converging in one direction.
In the middle of the sump channel, the leeches were stacking.
Layer upon layer, suckers latching onto suckers, bodies twisting around bodies, they began to grow upward from the water’s surface.
First came a pillar-like torso, and then the upper half of the main body began to differentiate.
A thick, branch-like structure extended from both the left and right sides, resembling arms.
The leeches at the top twisted into a ball, forming a spherical shape that looked like a head.
The aggregation was much faster than the time on the train; the entire process took less than ten seconds.
A Leech Amalgam nearly two and a half meters tall rose from the sump channel.
It was a size larger than the one on the train.
Lincoln’s brow furrowed.
He had read a passage in Marcus’s research log on the B1 level, and now he remembered it.
“The Leech Amalgam is already capable of maintaining a humanoid structure for over 72 hours, with the control core—namely, the Queen Leech’s command range—stabilized at a radius of about twenty meters.”
Ordinary leeches lacked the pheromone regulation of a Queen Leech and could not form such precise humanoid structures.
At most, they would gather into irregular lumps, unable to differentiate limbs or coordinate their movements.
There was only one explanation for the thing in front of them standing in humanoid form, growing arms, and making combat movements.
A Queen Leech was nearby, or somewhere further away, an entity that had evolved beyond the twenty-meter control limit was remotely manipulating these leeches.
Combined with the humming echoing from overhead, there was no need to guess the answer.
It was…
Marcus.
This amalgam hadn’t formed spontaneously; Marcus was controlling it from afar.
The humming in the pipes was proof of that.
He was declaring in his own way: *You are still within my domain.*
The humming continued, its low and slow melody almost perfectly synchronized with the squirming rhythm of the leeches on the amalgam’s surface.
The maw on the amalgam’s “head” was wide open, surrounded by three dense rings of suckers that made a gurgling, watery sound as they opened and closed.
It blocked the middle of the room, standing right between the three of them and the north wall exit.
Lincoln did not hesitate.
By the third second of the leeches’ aggregation, he had already unslung the M870 from his shoulder.
On the train, it had taken him three shotgun shells and four 9mm rounds to pierce the core.
The main reason was that it was his first time encountering the creature; he hadn’t known where the core was, and the first two shots had been exploratory.
Now, he knew.
The core was located in the upper-middle section of the torso.
It was darker than the surrounding areas, writhed at a different frequency, and was wrapped in four or five layers of tightly interlocking protective leeches.
His gaze swept across the amalgam’s “torso” and locked onto that area.