The bomb was in place. Pei Ran let out a breath—no more desperate sprinting for her life. She slowed down and pulled a small circular trigger for the NG_y8 from her pocket.
W warned her, "Pei Ran, you're too close. The blast radius will hit you. You need to move further before detonating. Also, be prepared—the explosion might cause the tunnel to collapse."
He was right. Pei Ran stopped where she was, waiting for the tunnel boring machine to move a bit further ahead.
The Thinker was still clinging to the rear of the machine, struggling.
Compared to the hulking behemoth of the tunneler, it looked almost dainty—though in reality, it was also massive, at least three or four meters tall.
Its entire body bore no trace of organic fusion. Instead, it was encased in a matte black metallic shell.
Its head was just as tightly sealed, but behind a transparent shield, what should have been a camera lens was... a single, solitary eye.
It blinked. It had eyelashes. Clearly human. The eyeball even moved, scanning its surroundings—deeply unsettling.
W calculated. "You're good. That should be a safe distance."
Pei Ran moved her thumb over the red section of the circular trigger, ready to press it.
Suddenly, the tunneler jolted.
Its pace slowed, as if it had hit resistance and was preparing to drill again.
But that jolt caused the Thinker, still stuck to the machine's rear, to jerk violently. Its black limbs came loose and it dropped off.
Mid-fall, the Thinker regained balance in a flash.
As soon as it hit the ground, its lower limbs reconfigured into a high-speed tread system, and it bolted into a side tunnel.
Too fast. In one fluid motion, it moved outside NG_y8's ten-meter blast radius.
Pei Ran and W: "…"
The tunneler, oblivious that it had lost its payload, rumbled forward carrying the bomb, shaking the earth. Meanwhile, the Thinker veered off, charging into the branching tunnel.
Bomb and target had officially parted ways.
Pei Ran sprinted forward again, reached the fork, and quickly dropped W from her back. "You go after the Thinker. I'll retrieve the bomb."
"Got it," W responded. He extended two folded mechanical arms downward and began "running."
Not quite as fast as Pei Ran, but fast enough to tail the mobile AI combat unit and keep it in sight.
Pei Ran pushed ahead.
The rocks ahead were harder to chew through, slowing the tunneler's progress, and she caught up. She grabbed a crossbeam on its rear, vaulted onto the conveyor belt, and snatched the NG_y8.
The fusion tunneler definitely carried green light too—but now wasn't the time to harvest it. First, the Thinker.
Before the machine could react, Pei Ran leapt off, retracing her path.
She veered into the side tunnel and immediately spotted the metallic orb ahead.
Without the tunneler's floodlights, the orb had switched on its own spotlight.
Its two metallic limbs touched the ground, moving in a way eerily similar to a running ostrich—springy, with joints folding opposite to those of humans. The spotlight beam bounced with every bounding step.
Had she not been in such a rush, Pei Ran might have laughed.
She caught up in no time and scooped him up. "You run weird."
W: "…"
Flatly, W muttered, "Are you mocking me? These folding arms weren't designed for running."
"I wasn't mocking. I said you're cute," Pei Ran replied.
"I seriously doubt your definition of 'cute,'" W deadpanned. "It's likely just a polite way to say 'funny-looking.'"
He emphasized, "I used to have a hover system. I was meant to fly."
Now he was reduced to being slung over her shoulder.
The Thinker certainly lived up to the "mobile" part of its name. It had already zipped far ahead.
Pei Ran asked, "It's a combat center—why doesn't it have any weapons for self-defense?"
Surely it could've at least tried to shoot its way free from the tunneler.
W replied, "It was supposed to have four detachable armed drones mounted. But the factory didn't get the chance to install them yet."
Lucky they didn't.
The Thinker reached the tunnel's end and swerved left out of sight.
Pei Ran, still carrying the metal orb, darted after it—turned the corner—and froze.
The scene before her was beyond belief.
In the middle of the tunnel the Thinker had just passed through, countless specks of green light were emerging from the wall.
Its core appeared first—a blindingly bright mass of concentrated green. Densely packed, indistinguishable individual points radiated outward in several wide, luminous spiral arms.
Each arm was composed entirely of those shimmering green specks.
Together they formed a colossal spinning disk. Galactic in form. A green spiral galaxy, tilted and glowing, lighting up the entire tunnel.
Dozens of kilometers away—
Heijing Base, Command Hall.
Marshal Veina and the ad-hoc decision committee had left the briefing room. All eyes were now on the central screen in the main hall.
The screen, segmented into views of the northern battlefield, now included a new feed: real-time progress of destroying the Thinker within the tunnel system.
In one corner of the feed—a swirling vortex of green light.
The vortex churned, spinning in place until it filled the tunnel.
The tunnel was eight or nine meters wide. The vortex even wider. Part of its spiral arms sank into the tunnel walls, the green lights effortlessly phasing through solid rock as they spun.
Marshal Veina commanded, "Agent W, enlarge the image."
The picture zoomed in rapidly, soon dominating the entire screen. Green light bathed everyone's faces in the control hall.
General Eugene whispered, "That's…"
W interjected, "...what we've previously referred to as a light vortex."
W explained, "The first discovery of this phenomenon came from Dr. Is, who was studying green light in fusion entities. But the largest one he found was only about forty centimeters in diameter. It wasn't until last night that we encountered a vortex of this scale on the northern front."
It was a monster.
Someone asked, "Is this the same vortex from last night? It seems... mobile."
"I don't know," W admitted. "The vortex constantly shifts form. I can't be certain."
"This kind is malignant," W warned. "According to Dr. Is, every point of green light inside the vortex generates a frenzied fusion entity. No one must approach it."
"No wonder we're seeing so many frenzied fusion entities nearby," someone muttered. "This might be the cause."
Bad luck to touch it.
But all eyes were now on the Thinker, which had darted through the tunnel just before the vortex emerged, and was now spinning calmly on the far side.
Fortunately, the tunnel it had entered was a dead end.
Unfortunately, the vortex completely blocked the path—no gaps, no way through. Pei Ran couldn't get close enough to plant the bomb.
Someone asked, "What's NG_y8's effective range?"
"Ten meters," W answered.
No calculation necessary. It was obvious—the distance from Pei Ran's location to the Thinker was at least two hundred meters.
General Song Wan asked, "Agent W, could your patrol robot carry NG_y8 through the vortex?"
W replied, "No. The vortex severely disrupts AI processing cores. My patrol unit would crash mid-crossing."
Veina quickly asked, "What about the NG_y8 itself?"
W nodded, "Its detonation mechanism is purely analog. It can survive passage through the vortex."
Song Wan considered, "Could Pei Ran throw it? Her mechanical arm should give her more range than a normal human."
W responded, "NG_y8 is heavy. I've checked her arm's specs—its throw is limited by the shoulder joint's human anatomy. Maximum range is 120 meters. Still not enough."
Veina frowned. "What if we use a drone to carry the bomb?"
"Same problem," W reminded. "Our drones also have AI cores—they'll fail inside the vortex."
Veina nodded. "So what we need is something completely non-AI. A simple device—like an electric toy car a child might play with. Just strong enough to carry the bomb through."
"Exactly," W confirmed. "I've already ordered Heijing's weapons workshop to build such a device. It's ready, and I'm rerouting a drone to deliver it."
Problem is, navigating the labyrinth of tunnels would take time.
Dozens of kilometers away—
Underground tunnels.
Pei Ran stared at the green galactic spectacle in awe.
"What is this thing?"
W's voice turned stern. "Pei Ran. Don't go near it."
"That's what we call a light vortex," he said. "To put it simply, it's a factory for frenzied fusion entities. Last night, we found a giant one like this. A major got too close and absorbed a mass of green light—turned into something... terrifying."
Pei Ran glanced at the Thinker, still spinning lazily at the tunnel's far end, then back at the massive green spiral.
"How terrifying?" she asked.
"He lost his mind within hours," W said. "At a field hospital near the front. He started absorbing everything—beds, chairs, medical equipment, doctors, nurses, soldiers... all of it. Everything around him became part of his body."
Pei Ran asked, "Then what?"
"We know how to kill frenzied entities now. We blew him up—heart and all—before he could grow into a full-blown abomination."
W repeated firmly, "Pei Ran, do not touch that vortex."
But the green lights pulsing inside Pei Ran didn't seem to agree.
The moment the light vortex appeared, Greenlight One—who had just been completely unresponsive—suddenly snapped wide awake. Greenlight Two and Three perked up as well, all three points of light darting madly through Pei Ran's body in a frenzy of excitement.
Food! Food!! FOOD!!!
They were desperately transmitting their hunger to Pei Ran.
She thought grimly: Can you guys even digest that thing?
They didn't care.
All they could say was: Hungry! Hungry!! HUNGRY!!!
But hunger alone wasn't a good enough reason to act recklessly.
Pei Ran turned to W and asked, "You can't get close to the vortex either, right? If you could, you'd have gone over there with a bomb already."
W replied, "Correct. The core processors of artificial intelligences like me are heavily affected. A robot would shut down."
So robots would go limp crossing the vortex?
That was perfect.
Pei Ran immediately began waving frantically at the Thinker on the other side of the green light. She jumped up and down, trying anything she could to get its attention.
The Thinker was an AI-powered robot. It definitely had a core processor too. When it passed through the tunnel earlier, the vortex hadn't appeared yet. But if she could lure it into turning back now and walking through the vortex again, there was a chance it might shut down—and all their problems would be solved.
W: "…"
W said, "Pei Ran, it's a fusion unit. The vortex might not affect it."
Still, Pei Ran kept waving and hopping with all her might. "Well, let's try and see. You never know until you try."
It might just work.
Unfortunately, despite its big, human-like eye, the Thinker might as well have been blind. It clearly didn't appreciate Pei Ran's dust-covered beauty, not even sparing her a glance. It stayed at the far end of the tunnel, spinning in place, trying to find another way forward.
Pei Ran had to calm herself and come up with a new plan.
She studied the shape of the glowing vortex. "W, look at the center of the vortex—it seems like the brightest part is up and to the left. If we hug the right wall and dig sideways, maybe we can carve out a path without hitting any green light."
W was speechless. "You want to dig a tunnel? What are you, a tunnel boring machine?"
Pei Ran glanced at his folded mechanical arms.
"With your two claws and my mechanical hand, it's not impossible."
Back when he was digging her out of the dirt, W's claws had been moving at lightning speed. If they kept that pace and started tunneling to the side, they might actually be able to make a crawlspace.
W had no choice but to give her the stats. "I've already sent a drone to deliver a small electric vehicle. Estimated time to locate us in the tunnel: thirty minutes. That's all we've got. There's no way the two of us can dig a path in that time. It's not worth the effort."
He added, "Besides, the vortex might shift before the drone gets here."
The light vortex could move. And if it happened to shift away and open up the path, they could just head straight through and blow the Thinker up.