The heavy iron key turned in the lock with a sound like a pistol shot in a canyon. Click-CLACK.
Eiden held his breath, his muscles coiled, waiting for a siren, a shout, or the hiss of gas. Silence stretched out, heavy and absolute.
He pushed the heavy steel door open. It swung inward on silent, well-oiled hinges—too smooth for a school basement—revealing a corridor that shouldn't exist.
Behind him lay the mundane reality of St. Swithin's: the smell of damp mops, old boiler fumes, and the comforting clutter of a maintenance area.
In front of him lay a cold, sterile void.
The corridor was lined with smooth, cold concrete that seemed to absorb the light rather than reflect it. The illumination came from low-wattage LED strips running along the floor, casting long, upward shadows that made the walls seem to lean in. The air was frigid, recycled, and chemically pure; it smelled of ozone, high-voltage electricity, and the terrifying scent of nothingness.
"I'm in," Eiden whispered into his throat mic, the vibration of his own voice feeling alien in the dead air. "It looks like a bunker. Or a tomb."
"Hold," Hazel's voice cut through the static, sharp and urgent, shattering the quiet in his ear. "Don't take a single step. Look at the floor. Really look at it."
Eiden froze, his boot hovering inches above the threshold. He looked down. The floor wasn't concrete like the walls. It was a grid of black, metallic tiles, each one exactly one foot wide, separated by thin lines of matte silver. They looked like the scales of a giant, sleeping reptile.
"I see it," Eiden said, a cold sweat breaking on his neck. "Tiles."
"It's a pressure grid," Hazel said, her voice rapid-fire. "Akuma isn't just paranoid; he's meticulous. Those tiles aren't just floor; they're independent piezoelectric sensors. They measure weight distribution, stride length, and impact force. If you walk normally, the algorithm will recognize a human gait within three steps and trigger the silent alarm. The guards won't come running; the doors will just seal, and they'll vent the oxygen from the corridor."
"Suffocation," Eiden muttered, eyeing the heavy blast doors at the far end. "Charming. A quiet way to die."
"How do I cross? Levitate?"
"You have to move like the building," Harry chimed in, his voice trembling so hard the static seemed to shake. "I'm reading the seismic sensors in the foundation. The school's heating pipes... the main boiler... it's ancient. It creates a rhythmic, hydraulic thrum every six seconds. A massive vibration that travels through the bedrock."
Eiden closed his eyes. He stopped breathing. He listened.
At first, nothing. Then, he felt it through the rubber soles of his shoes. A deep, subsonic pulse. Like a heartbeat buried in the earth.
Thrum... pause... thrum... pause.
"When the boiler pulses," Harry explained, sounding like he was hyperventilating, "the sensors vibrate. They create a blind spot—a calibration reset—for exactly 0.5 seconds. You have to step with the pulse. You have to become invisible to the machine."
Eiden looked down the hallway. It was fifty yards long. That was a hundred steps. A hundred moments where death was half a second away.
"Half a second," Eiden whispered. "Okay."
He closed his eyes again, finding the rhythm. He pushed the pain of his broken ribs into a small, dark box in his mind. He ignored the throb of his burned hand. The Wolf inside him woke up, its senses sharpening until the subsonic thrum sounded like a drumbeat.
Thrum.
He stepped. His boot hit the black tile.
Silence. No alarm. No hiss of escaping air.
Thrum.
He stepped again.
It was an agonizing dance. Step. Freeze. Step. Freeze. Sweat beaded on his forehead, stinging his eyes, but he couldn't wipe it away. His ribs burned with the effort of holding his body perfectly rigid between pulses, forcing his muscles to lock and unlock with mechanical precision. One cough, one stumble, one muscle spasm, and the room would become a vacuum-sealed coffin.
Halfway down the hall, disaster struck.
His boot found a slick patch of oil, invisible on the black metal.
He lurched forward, off-rhythm, his weight shifting dangerously fast.
"Eiden!" Hazel gasped in his ear.
Eiden didn't try to catch his balance with his feet—that would trigger the sensors. He threw himself forward, launching his body into the air. He caught his weight on his fingertips and the tips of his toes, freezing in a plank position just as the pulse ended.
His broken ribs screamed in white-hot agony. His vision swam with black spots. The strain on his core was unbearable.
He held it. Hovering inches above the sensors, a human bridge over a digital abyss.
Thrum.
He moved his hand forward six inches.
Thrum.
He moved his right knee.
He crawled the rest of the way, moving like a spider, synchronized with the heartbeat of the machine. Step by excruciating step.
When he finally reached the safe concrete platform at the far end and rolled through the doorway, he lay there for a full minute, gasping for air, clutching his side.
"I'm across," he wheezed, his voice ragged.
"Your heart rate spiked to 180," Hazel noted coolly, though he could hear the relief in her breath. "Try to relax. You have three more levels. And Eiden? The next one is colder."
While Eiden danced with sensors, Emily and Linda were descending into a different kind of hell.
The "Architect's Entrance" was not a staircase. It was a throat.
It was a narrow, brick-lined shaft that dropped straight down into the crushing darkness. The air was thick with the smell of centuries-old soot and decay. The iron rungs of the ladder were rusted to flakes, slick with condensation that felt like slime.
"I can't do this," Linda whimpered from above, her voice echoing strangely in the tight space. "It's too tight. The walls... they're touching me. I can't breathe, Em."
"Keep moving," Emily commanded from below. She held the heavy flashlight in her teeth, the beam cutting a erratic cone through the swirling dust motes. Her jaw ached, but she couldn't use her hands. "Don't look up. Don't look down. Just look at your hands. Rung by rung. If you stop, you freeze."
They had descended perhaps fifty feet when the atmosphere changed violently.
The stale stillness was replaced by a wind. A strong, constant, howling updraft that smelled of grease, hot metal, and stale air.
And a sound. A low, terrifying, mechanical ROAR that vibrated in their teeth.
Emily stopped. The ladder ended abruptly in jagged metal.
Below her was a metal grating. And below that...
"Oh, god," Emily whispered, taking the flashlight from her mouth, her hand shaking.
They were in a massive, cylindrical ventilation shaft, wider than the library above. Directly below them, spanning the entire width of the shaft like a monstrous mouth, was an industrial fan.
The blades were massive, each one the size of a man, made of sharpened steel. They spun with a blur of speed that created the roaring wind, a vortex that threatened to suck them down. It was a meat grinder the size of a house.
"What is that?" Linda shrieked over the noise, clinging to the ladder like a frightened cat.
"Main ventilation," Emily yelled back, her hair whipping around her face. "We have to get past it."
"Past it?! It'll chop us into sushi! We're going back!"
"There!" Emily pointed with the light, ignoring her.
In the center of the spinning blades, there was a stationary hub—the motor housing. It was a small island of stability in the chaos. And leading to it, a narrow, grease-slicked maintenance catwalk, no wider than a balance beam, suspended over the spinning death.
"We have to climb down to the catwalk, walk to the center hub, and there should be a service hatch. It's the only way down."
Emily went first. She lowered herself from the ladder onto the swaying catwalk. The metal groaned under her weight. The wind from the fan whipped her coat violently, trying to throw her off balance. One slip, and she would fall into the blades. There would be no body to recover.
She forced herself to move, hand over hand on the safety rail, her eyes locked on the hub. She made it. She found the hatch. It was rusted shut, sealed by years of neglect.
She pulled. It didn't budge. She grunted, putting her back into it. Nothing.
"Linda! Come down! I need help!"
Linda was still clinging to the ladder, paralyzed by terror. "I can't! The wind! It's pulling me!"
"Linda!" Emily roared, her voice cracking with desperation. "If you don't come down here right now, I am leaving you! Do you hear me? I will leave you in the dark! Move!"
The threat worked. Sobbing, Linda climbed down. She didn't walk; she crawled on her hands and knees across the catwalk, her eyes shut tight, screaming silently.
Together, they grabbed the wheel of the hatch.
"On three!" Emily yelled over the roar. "One! Two! Three!"
They pulled. The rust screamed in protest. The wheel turned.
The hatch popped open with a violent clang.
But the force of the release threw Linda off balance. Her hand slipped on a patch of old grease.
She slid sideways. Her legs went over the edge of the catwalk.
Her feet dangled inches above the blurring, screaming steel blades. The wind tugged at her shoes.
"EMILY!" The scream was raw, primal.
Emily didn't think. She lunged.
She grabbed Linda's wrist with both hands, bracing her feet against the railing. The sudden weight of her cousin jerked her forward, threatening to pull them both into the grinder.
Emily gritted her teeth, her muscles screaming. She channeled every ounce of strength her father had forced her to build in the gym, every push-up, every pull-up.
"I've got you," she screamed, her face contorted with effort. "Climb! Climb, damn you!"
Linda scrambled, kicking her legs wildly, finding purchase on the railing. Emily hauled her up, and they both collapsed onto the safe metal of the hub, panting, the fan roaring hungrily beneath them.
Linda looked at Emily. Her eyes were wide, the pupils dilated with shock. "You... you saved me."
"Don't get used to it," Emily gasped, wiping grease and sweat from her face. Her hands were trembling now. "Now get in the hatch. Before I change my mind."
Eiden moved deeper. The "Hall of Silence" had led to a stairwell that seemed to descend into the earth's core.
As he descended, the architecture changed. The modern, militaristic concrete of the bunker gave way to something older. Red brick. Arched doorways. Gas-lamp fixtures that had been converted to electric.
He passed a door that had rotted off its hinges. He shined his light inside.
It was a classroom.
But not a modern one. There were rows of wooden desks, rotting and covered in a thick carpet of gray dust. A chalkboard on the wall still had faint, ghostly writing on it—Latin conjugations. The calendar on the wall, yellow and curling like dead skin, read October 1924.
Eiden felt a chill that had nothing to do with the cold air.
Akuma hadn't just built a bunker. He had built his school on top of an older, forgotten structure. He had buried the past to build his future. What happened to the students who sat at these desks? Why was this place sealed up like a tomb?
"Hazel," Eiden whispered, shining his light on a discarded textbook. "I'm in the old sector. It looks like... a tomb. A school that died."
"Keep moving," Hazel said, her voice tight with unease. "The blueprints show a structural anomaly ahead. You're close to the convergence point. And Eiden? Be careful. Ghosts aren't the only thing down there."
Emily and Linda dropped through the fan hatch, sliding down a chute, and landed on a cold stone floor.
It was quiet here. The roar of the fan was muffled to a distant hum.
They were in a long, brick tunnel, the ceiling low and arched. Water dripped from the ceiling, forming stalactites of rust.
"Where are we?" Linda whispered, her voice echoing.
"The foundation," Emily said, standing up and brushing herself off. "The roots of the empire. The place where the money is kept."
They walked. The tunnel sloped downward, deeper and deeper.
Eventually, it ended at a massive, circular steel door with a wheel valve in the center. It looked like the airlock of a submarine, out of place in the brick tunnel.
At the exact same moment, on the other side of the room, another heavy door groaned and opened.
Eiden stepped out, his flashlight cutting the gloom.
Emily stepped out, her light raised.
They froze.
They were standing on opposite sides of a large, cylindrical concrete chamber, the floor covered in a shallow layer of black water.
Emily raised her flashlight. The beam hit Eiden's face, illuminating the sweat, the bandages peeking out from his collar, the exhaustion in his eyes.
"You," she breathed, her hand instinctively going to her empty holster.
Eiden raised his light. It hit Emily's face, showing the grease streaks, the fear, and the fierce determination.
"You," he said, his voice flat.
Linda peeked out from behind Emily, squinting into the light. "Oh, thank god. It's just the peasant."
The two teams had collided. And they were deep, deep underground, with millions of tons of rock and secrets above their heads.