Chapter 20: Choke Point

They ran.

But running in a tunnel was a fool’s game.

The serpent didn’t just chase them; it flowed through the dark. The rumble of its massive, coiled body vibrating through the concrete floor was a constant, terrifying reminder of how close it was. It was in its element, and they were just prey stumbling through its dining room.

"Keep moving!" Darwin barked, his voice echoing sharply off the curved walls. "Don’t look back!"

Gio sprinted alongside Melody and Lloyd, his lungs burning. His wasp construct hovered ahead, its white glow illuminating the narrow corridor just enough to keep them from tripping over loose cables and debris.

Behind them, the chittering roar of the serpent grew louder. It was gaining.

"Commander!" Reuben shouted, his stone-hardened skin scraping against the tunnel wall as he ran. "Too fast! We can’t outrun it in here!"

Darwin didn’t slow down. His pupils, bionically engineered, scanned the passing walls, reading faded stenciled signs in the dim light. "There. Up ahead. Sector maintenance bulkhead."

Fifty meters down the tunnel, a massive, circular steel door spanned the width of the corridor. It was old-world military grade, thick as a bank vault, currently recessed into the walls in the open position.

"We seal it," Darwin ordered, not breaking stride. "Buys us time."

"How?" Lloyd panted, clutching his side. "Controls are on the other side!"

"Manual override." Darwin pointed to a heavy, rusted iron wheel set into the wall just beside the door frame. "Someone turns it. Rest of you get behind that door the second it starts moving."

The plan was simple. It was also a suicide mission for whoever turned the wheel. The serpent would be on them before the door was halfway closed.

"I’ll do it," Kojiro said. His voice was calm, but the purple veins on his temple were pulsing violently.

"Negative," Darwin snapped. "You’re our best close-quarters fighter if it breaches. Not risking you on a rusted crank. We don’t even know the full extent of your teleportation yet."

"Then send one of the other prisoners!" Melody demanded, her claws already extended, her tail lashing. "Send Rask! He’s huge—he can turn it!"

"Rask is too slow. Bone spikes’d get caught in the mechanism." Darwin didn’t even look back at the huddled, terrified prisoners.

"And the rest of them are panicking. None of ’em have the speed or the nerve to turn that and get behind the door before it crushes them."

"Then who?" Melody shot back.

"I am," Gio said.

He didn’t wait for permission. He stopped running, planting his feet firmly on the cracked concrete. He turned to face the darkness they had just fled.

"Get to the door," Gio ordered the squad. "Now."

"Gio, are you insane?" Melody yelled.

"Go!"

Reluctantly, the recruits and soldiers sprinted past him, positioning themselves behind the thick steel lip of the bulkhead. Darwin lingered for a fraction of a second, his expression unreadable, before he too stepped behind the cover.

Gio stood alone in the corridor. He closed his eyes and reached into his Bioenergy reserves.

’Come.’

Four wasp constructs materialized in a flash of white light.

[Bioenergy: 44%]

The tunnel shook. The serpent rounded the corner.

It was a nightmare of pale, segmented armor and blind, milky eyes. Its maw was a vertical slit lined with rows of translucent, needle-like teeth. It lunged, moving with the terrifying speed of a striking viper.

’Distract it,’ Gio commanded.

The four wasps shot forward. They didn’t attack to kill; they attacked to annoy. They dive-bombed the serpent’s face, stinging at its blind eyes and sensitive jaw hinges.

The serpent thrashed, its massive head whipping side to side. It snapped its jaws, catching one wasp and crushing it into mist.

[Construct destroyed. Reconstructing. 1%]

The wasp instantly reformed in mid-air and dove right back into the serpent’s open maw.

Another snap. Another crush. Another 1% drain.

Gio stood his ground, his mind locked in a rhythm of command and reconstruction. The wasps were a swirling vortex of white light and stingers, a relentless, immortal swarm that forced the massive predator to focus entirely on the gnats in front of it.

[Bioenergy: 40%... 36%... 32%...]

It was working. But the serpent was getting angry. It reared back, its body coiling like a massive spring, preparing to unleash a devastating, tunnel-collapsing strike.

"Now, Kojiro!" Gio screamed.

Purple smoke erupted beside the manual override wheel. Kojiro materialized, his katana already sheathed, both hands grabbing the rusted iron crank.

He heaved. The metal groaned, rust flaking off in showers of orange dust.

The serpent heard him. It abandoned the wasps, its blind head snapping toward the sound of the grinding metal. It lunged, its massive jaws opening wide enough to swallow Kojiro whole.

"Kojiro, move!" Gio yelled.

Kojiro didn’t let go of the wheel. Instead, he did something Gio had never seen him do.

With his free hand, he reached into his tactical pouch and pulled out the F-Rank Mutagenic Tunnel Worm core—the one Gio had given him days ago.

He popped it into his mouth and swallowed it whole.

For a split second, nothing happened.

Then Kojiro’s body violently spasmed. The purple veins on his skin flared blindingly bright, spreading across his entire body like lightning. His eyes rolled back, and his mouth opened in a silent scream.

His body began to dissolve.

Not partially. Not just his arm or his legs. His entire body turned into thick, swirling purple smoke, expanding outward like a cloud.

The serpent’s jaws slammed down on him.

But there was nothing to bite.

The smoke cloud dispersed, reforming instantly on the other side of the serpent’s head. Kojiro solidified, his body flickering between flesh and vapor, and used the serpent’s own momentum to throw himself backward, spinning the wheel one final, desperate time.

The massive steel bulkhead slammed shut with a deafening, hydraulic CLANG.

A split second later, the serpent’s head smashed into the outside of the door.

The entire tunnel shook. Dust rained from the ceiling. A deep, furious screech vibrated through the steel, so loud it made Gio’s teeth ache. Then came the sound of massive, heavy impacts. Thud. Thud. Thud.

It was trying to break through.

But the old-world steel held.

Silence slowly returned to the tunnel, broken only by the heavy, ragged breathing of the recruits and the faint, fading screeches from the other side of the door.

Gio dismissed his wasps. The white light vanished.

[Bioenergy: 28%]

He slumped against the wall, his legs trembling from the mental strain of holding four constructs and managing the rapid respawns.

"Everyone okay?" Darwin’s voice cut through the quiet. It was calm. Steady. As if they had just completed a routine drill.

A chorus of shaky affirmatives answered him.

Gio pushed himself off the wall and walked over to where Kojiro was sitting on the floor, leaning heavily against the cold steel of the blast door.

Kojiro looked like hell. His skin was pale and clammy, his breathing shallow. The purple veins on his body were fading, but they left behind a web of dark, bruised lines that looked like cracks in porcelain. He was shaking.

But he was smiling. That same lazy, infuriating grin.

"Nice timing, kid," Kojiro wheezed, looking up at Gio.

"What the hell was that?" Gio demanded, dropping to his knees beside him. "You ate the worm core. Turned your whole body into smoke. You couldn’t do that before."

Kojiro’s grin faltered for a second. He coughed, a wet, rattling sound.

"Temporary boost," he whispered, his voice strained. "Devouring a core without a Mutagenic Core to process it properly... it’s like drinking jet fuel. Burns hot, burns fast. But for a few seconds, it let me go full vapor. Not just parts. All of me."

He held up his trembling hand. The purple smoke flickered around his fingers for a moment, then faded.

"Costs me, though," he admitted. "My body’s not built for this. I’m tearing myself apart from the inside. Give it a few hours, I’ll be back to normal. Maybe."

"Maybe?" Melody’s voice was sharp with worry. She knelt beside him, her cat ears flat.

"Maybe I’ll be fine. Maybe I’ll cough up blood for a week. Maybe I’ll pass out." Kojiro shrugged, then winced as the movement clearly hurt. "Point is, I’m alive. And so are you."

Gio stared at him. Kojiro had just risked his life—not just in the tunnel, but by devouring a raw core without the proper biology to handle it. He’d gambled everything on a few seconds of full-body smoke transformation.

"You’re an idiot," Gio said quietly.

"Yeah, well," Kojiro coughed again, wiping a trickle of blood from the corner of his mouth. "Takes one to know one."

Darwin approached, looking down at Kojiro’s shaking form. He didn’t offer medical aid. He didn’t offer praise.

"Door’ll hold about twenty minutes before the tunnel’s structural integrity gives way to that thing’s thrashing," Darwin stated flatly. "We move. Now. Deeper into the network."

"Commander," Melody said, stepping forward, her voice tight with anger. "He’s injured. We need to stop. We need to treat him."

"No time to treat him," Darwin replied, his gaze cold and unwavering. "We stop, we die. We keep moving, we might find another bulkhead. Or an exit. Those are the only variables that matter."

He turned his back on them and started walking down the dark, narrowing tunnel.

"Move out."

Gio looked at Kojiro. The older man gave a weak, dismissive wave with his trembling hand.

"Go on, kid," Kojiro muttered. "I’ll keep up. Just... give me a second."

Gio hesitated, then stood up. He fell into step beside Melody as the squad followed Darwin deeper into the suffocating dark.

Behind them, the steel door groaned under another massive impact.

And ahead of them, the tunnel only grew colder, darker, and more silent.

Whatever was waiting at the end of this network, Gio realized with a sinking dread, was going to be far worse than a blind serpent.