Chapter 4: Sword Shadow Phantom Walk: Automated Sword Flight in the Subway Station

The lights in the subway station flickered on and off, eerily reminiscent of faulty indicator lights in a server room. Shen Yan crashed heavily onto the tiled floor, his knee hitting with a dull thud. His phone screen cracked a line, but the Terminal Interface was still flashing—【Mental Power Remaining: 8%】—with an unread notice hanging in the lower right corner: 【Flight Log Anomaly, Detected High-Energy Rune Fluctuations on Underground Level Three】.

He panted as if he had just finished a full-stack interview, his ears ringing incessantly. But before he could catch his breath, the ground began to seep blood.

Not a metaphor—real blood. Dark red patterns spread from all directions, as if someone had written a “forbidden zone” in Code, slowly closing in. Several passengers on the platform stood rigid, their eyes vacant, dragged toward the center by an invisible force. Their Shadows stretched long and distorted into eerie symbols, clinging to the ground and becoming part of the Formation.

“Again?” Shen Yan gritted his teeth and pushed himself up, looking up to see a man in a black robe standing in the shadows. A bone knife dripped blood in his hand, and the rhythm of the incantation he muttered was as layered as Python decorators, one layer nested within another.

Ye Zhao stood three steps away, her sword half-drawn from its sheath, the Frost Soul Sword humming like an alarm. But she couldn’t move—several blood chains wrapped around her wrists, ankles, and even coiled around her neck, tightening the more she struggled. Her face was pale, veins throbbing at her temples, clearly suppressing the rampaging Sword Qi within her.

“Move again, and they die,” the man said without looking up, his voice hoarse. “Blood Soul Formation, five living sacrifices to open the ancient Earth Vein Formation. I won’t kill you, just borrowing your Sword Qi.”

Shen Yan stared at the bone knife in the man’s hand and suddenly laughed. “Buddy, this is a classic case of unauthorized resource access.”

The man froze.

Shen Yan had already opened his phone and created a new file: auto_sword_control.py.

First line: from Spiritual Energy Protocol import Sword Spirit Interface

Second line: class AutoSwordFlight(Coroutine Task):

Third line: def init(self, Sword Master): self.bound_target = Sword Master

“What are you doing?” Ye Zhao hissed, her voice strained with pain.

“Installing a Driver for you,” he replied, fingers flying across the screen. “Your sword is lagging like a 3D game without a graphics card.”

Before he finished speaking, a System Popup Window appeared: 【TypeError: Sword Spirit Unauthorized Access】

“Damn, not enough Permission?” Shen Yan frowned, catching sight of the red marks on Ye Zhao’s skin from the blood chains. He suddenly remembered the leap from the rooftop half an hour earlier—she could have stabilized her flight on her own, yet she turned back to protect him.

He took a deep breath and added a line at the end of the Code:

request.trust_level = ‘partner’

Enter.

A flash of green light.

【Trust Authentication Passed, Binding Sword Spirit Protocol】

【Data Stream Injecting…】

The Frost Soul Sword trembled violently, its blade revealing a dense, faint green grid, as if being Recompiled by some invisible Program. Immediately after, the sword lifted automatically, hovering three inches above the palm, trembling slightly in response to the Command Shen Yan typed.

“Holy… it actually connected?” Shen Yan’s eyes lit up. “Let’s try a looped slash—”

Code execution:

for i in range(5):

Sword Qi Release (Intensity=70%, Trajectory=Spiral)

Buzz! Buzz! Buzz!

Sword light exploded like a tidal wave, each slash precisely striking the weakest nodes of the blood chains. With a crack, the chain wrapped around Ye Zhao’s neck snapped and fell away.

“You—” She turned back in shock.

“Don’t get distracted!” Shen Yan shouted, “Right now, you’re an NPC—listen to my command!”

He added another line:

if blood_chain.reconnect_attempt3:

trigger.counter_protocol(type=shockwave)

As soon as the words left his mouth, the blood chain indeed lunged again. But just as it was about to entangle her, the Frost Soul Sword automatically triggered the preset counterattack. A ring-shaped Sword Qi swept out horizontally, shattering the entire blood web into fragments.

The man in black robes roared, “Impossible! What kind of evil sorcery is this?”

“This isn’t evil sorcery,” Shen Yan sneered. “It’s automated testing, specifically designed to deal with manual-mode villains like you.”

He was about to continue entering commands when suddenly, his vision went dark. His head felt as if it had been struck by a hammer. His Mental Power bar hit rock bottom, and his phone screen flickered twice, nearly shutting down.

“Warning: Core Thread overloaded. Recommend terminating the Run immediately.” The System’s Notification Tone rang out coldly.

“Shut up!” He slapped the screen. “If we cut it off now, we’ll both become Formation Eye fuel!”

He bit the Tip of his Tongue, forcing himself to concentrate, pouring his last bit of Mental Power into the Program. At the same time, he caught sight of Ye Zhao kneeling on one knee, her sword-gripping hand trembling—she was also holding on by sheer will.

“Hey,” he suddenly spoke, his voice not loud. “Do you remember back on the rooftop, when you said I couldn’t be a thief?”

She looked up, a flicker of light in her eyes.

“I’m telling you now—” He slammed the Tip of his Finger onto the enter key. “I’m not a thief. I’m from the development team.”

The Code roared to life.

auto_sword_control.py loaded the ultimate module:

if enemy enters berserk state:

execute(mirror_image_protocol)

and trigger(blood_energy_rebound.exe)

The next second, the man in black robes suddenly slashed his wrist, spraying blood onto the Formation Eye as he shouted fiercely, “With my blood as the guide, summon the earth-fiend spirit!”

The Blood Soul Formation instantly activated, a crimson light soaring upward, pressing against the ceiling. But just as the Energy converged, the Program captured the blood flow frequency and automatically adjusted the parameters in reverse. The Formation patterns abruptly reversed, and the Energy originally surging toward the Formation Eye flowed back into the caster’s body instead.

“What?!” Before the man could finish his cry of shock, the blood he had spilled seemed magnetically attracted, pouring back into his wound. His right arm instantly swelled and turned black, the bone blade clattering to the ground.

“You’ve got it wrong,” Shen Yan slowly stood up, the phone screen reflecting his reddened eyes. “For a sacrificial ritual, someone has to be willing. They weren’t willing, so you’re the only sacrifice.”

The man staggered backward, his right arm already festering and oozing pus, his face filled with disbelief. “You… what are you?”

“A worker pushed to his limits by 996,” Shen Yan stuffed his phone into his pocket. “And by the way, the Formation you wrote has a logical Vulnerability—you didn’t add an else to the if condition, so when something goes wrong, you don’t even know where to shift the blame.”

The man wanted to say something more, but suddenly, the ventilation duct exploded. He leaped into the pipe, his figure swiftly disappearing into the darkness. The blood patterns on the ground dimmed accordingly, and several passengers collapsed, breathing steadily as if they had just woken up.

Alert cleared.

Shen Yan’s legs gave way, and he slumped onto the cold floor. His phone was still running the monitoring program, but he no longer had the energy to look. His ears buzzed, his vision blurred, and he couldn’t even muster the strength to lift a hand.

“You’re insane.” Ye Zhao walked up to him, the tip of her sword lightly tapping the ground, her voice as cold as frost. “Using my sword for experiments—aren’t you afraid I’d turn around and cut you down?”

“Terrified.” He grinned, blood seeping from the corner of his mouth. “But you didn’t cut me down, which means you trust me.”

She fell silent for a moment, then suddenly bent down, reaching out to steady his shoulder. The warmth of her palm seeped through his shirt, steady and firm.

“Next time,” she said quietly, “don’t decide my fighting style for me.”

“Then next time, tell me the password.” He coughed twice. “I’ll upgrade you to two-factor authentication.”

She didn’t smile, but the tension around her eyes eased slightly. As she turned, the Frost Soul Sword traced a shallow mark on the ground, its lingering emerald code trailing along the blade and hanging in the air for a few seconds before slowly dissipating.

In the distance, a train roared into the station, the wind whipping through her hair. Leaning against the wall, Shen Yan watched her retreating figure and suddenly felt that this rundown subway station was a bit like the first line of code he’d ever written that actually ran—messy, but alive.

His phone vibrated.

New message:

【Detected residual signal in Underground Pipeline Network】

【Frequency match: dashcam from car accident scene seven years ago】

His pupils contracted. Just as he was about to tap to open it, Ye Zhao suddenly turned back.

“Don’t look.” She stared at him, her tone leaving no room for argument. “If you go digging now, you’ll only end up dead on the way.”

He looked up, ready to argue, but noticed the tip of her sword trembling slightly in her hand—not from injury, but from emotion.

“You… know something?” he asked.

She didn’t answer, only sheathed her sword, the sound of metal grating unnervingly clear.

The platform lights stabilized, casting a steady glow between them. The floating green code hadn’t fully dissipated yet, hovering quietly in the air like an unfinished sentence.

Shen Yan reached out to touch it, the tip of his finger slightly cool.

The code suddenly rearranged itself, forming two words:

Wait

(End of Chapter)