The Molten Heart Tower

Fu Feng stepped forward, and the stone door slid open automatically. There was no sound, no vibration; the stone walls on either side simply retracted inward, revealing a pitch-black corridor.

Lu Yan followed him across the threshold. The moment his foot landed, two rows of lights—one green, one orange—suddenly lit up on the walls of the corridor, flashing alternately. The light was not blinding, but rather very soft, just enough to illuminate the path beneath their feet.

The floor was made of blue-gray stone bricks, their edges inlaid with fine copper threads that had been polished smooth and bright by years of footsteps. The air carried a faint scent of rust, mixed with the smell of ash left behind after some kind of ore had been burned.

“Spiritual aura recognized. Holder: Fu Feng. Welcome back to the sect.”

A voice echoed from deep within the corridor—ethereal, completely devoid of emotion, and distinctly non-human.

Lu Yan recognized the tone; it inexplicably reminded him of Siri. Standing two paces behind Fu Feng, his footsteps paused. Artificial intelligence? Or something else?

Fu Feng continued walking as if he hadn't heard a thing. Lu Yan caught up to him. Watching the lights alternating on both sides, he felt as though he had stepped into a world he was completely unprepared for. Before entering, he had assumed the Artifact Sect was just a “smithing sect,” but now he realized they were already building “systems.”

After another dozen steps, a heavy thud of footsteps echoed from ahead, as if something massive were approaching. Lu Yan stopped and squinted into the darkness, but he couldn't make out what it was.

The thing moved very slowly, each step accompanied by the screech of metal scraping against stone. A tall figure emerged from the darkness, clad in a black-and-green metal shell. Dark runes were embedded in its joints, and its head was a flat, featureless metal mask.

It stood a full head taller than Fu Feng, with shoulders twice as wide as an ordinary man's. Standing in the middle of the corridor, it looked like a moving wall. It stopped three paces away from Fu Feng, its metal mask bowing slightly as it let out a muffled, rumbling voice:

“Greetings, Young Sect Master.”

Fu Feng didn't stop, merely raising a hand in acknowledgment. “Mmh.”

The iron man said nothing more, stepping aside to stand against the wall again. Lu Yan stared at the iron figure for a couple of seconds without slowing his pace. Fu Feng was already walking away. He withdrew his gaze and quickened his steps to catch up.

Lu Yan really couldn't keep his composure any longer. In his mind, he reviewed everything he had just witnessed: an automated stone door, spiritual aura recognition, some kind of system voice broadcast, and now this. Out of the corner of his eye, he glanced back—the iron man was still standing by the wall, motionless, its mask facing in his direction as if it were still watching him. He tugged at Fu Feng's sleeve, leaning in and lowering his voice. “What on earth is that?”

Fu Feng stopped, glanced back at the iron man, and then looked at Lu Yan. He raised an eyebrow; he had expected Lu Yan to ask much sooner. After all, on their way in, from the corridor to the stone door to the spiritual aura recognition, Lu Yan hadn't uttered a single word, as if his ability to accept all of this was much faster than Fu Feng had anticipated.

“You know,” Fu Feng said, slowing his pace, “over the past twenty years, those people from the Central Continent have been annexing territories everywhere. Many small and medium-sized sects couldn't survive. Even first-rate sects like the Beast Taming Sect and the Joyous Union Sect were swallowed up, let alone the smaller ones that didn't even leave their names behind.”

He glanced at Lu Yan, as if confirming whether he was listening. Lu Yan was indeed listening. Fu Feng continued, “Many marginalized cultivators who couldn't survive elsewhere sought refuge with the Artifact Sect, bringing along the last remaining legacies of their sects. Machinery, puppets, soul arts—you name it.” He paused, looking at Lu Yan. “Did no one from your Formation Sect come to seek refuge?”

Lu Yan turned his head away. He couldn't very well say, “The Formation Sect looks so dirt-poor and miserable that anyone would probably run away at first glance.”

But that was pretty much the truth—and he had to blame the old man for it. The old man wouldn't even spend money to repaint the peeling mountain gate, insisting on placing a formation over it instead. As a result, anyone trying to enter had to crack the formation first, which effectively blocked all potential refugees outside...

Fu Feng didn't press him. He continued walking, his tone flattening slightly. “The one just now is called Soul Carrier One. It was a joint project between the Soul-Gathering Hall, the Ingenuity Sect, and us.” He turned his head. “It uses a soul banner as the core, endows it with life using remnant souls, and uses the Ingenuity Sect's dharma puppet technology as the outer shell.”

“Theoretically, it's feasible, but our current technology isn't quite there yet.” His voice didn't waver as he spoke, but Lu Yan could tell he was intentionally keeping his tone flat. “It can only operate for two hours a day, and it only possesses sight. No hearing, no touch, no smell, no taste.” He paused. “Those souls... are all cultivators who luckily left behind remnant souls after dying in battle. They use this method to... drag out a feeble existence.”

He fell silent for a few breaths, his voice tinged with loneliness. “Those soul banners... will also wear down over time. If the remnant souls stay inside for too long, they will eventually be ground away. Once the soul banner shatters completely, they will also... be completely gone.”

Lu Yan nodded. He didn't ask further, nor did he look back. He followed Fu Feng forward. “...Let's not talk about that,” Fu Feng forced a smile, quickening his pace. “Let's go.”

After walking for a while longer, the corridor began to widen. The walls on either side gradually receded, and the ceiling rose higher. Light flooded in from ahead—not from lamps, but a warmer, orange-and-gold glow. Finally, they reached the end of the passage. Fu Feng stepped aside, and Lu Yan took a step forward, standing at the edge of the exit. A blast of hot wind swept over him, and a breathtaking sight suddenly opened up before his eyes.

It was an inverted pagoda, with its tip pointing downward and its base at the top, looking as if it had been driven upside down into the mountain from deep underground. Wood and metal building materials were stacked and interwoven, spiraling downward layer by layer, narrowing and deepening the further down it went.

Running straight through the very center was a colossal glass tube. It plunged from the very top down into the unseen depths of the bottom-most floor, filled with a flowing, viscous, reddish-gold liquid. The liquid surged slowly and rhythmically within the tube—rising and falling like the beating of a giant heart. With every “beat,” the reddish-gold liquid flowed along pipes to the various levels of the pagoda, like a web connecting the entire structure.

Lu Yan stared at the glass tube for a long time. It reminded him of a movie—a group of people trapped in a vertical tower, where food was sent down from the top, getting scarcer the lower it went.

Then he thought of another movie—a giant glass pipe filled with flowing chocolate, where a little boy got sucked inside. He suppressed both of these mental images, focusing his attention back on the wonder before him.

Fu Feng walked over to his side, following his gaze toward the glass tube. “Welcome to the core of Everspring City. This is the Molten Heart Tower.”

“When we first came to Everspring City eight years ago, we originally wanted to see if there were any rare minerals inside this volcano. As it turned out, we dug deep for seven months and ended up unearthing this thing.”

“It contracts and expands like a heart in the deepest depths. It was incredibly hard. We had to rely on a Heaven Rank weapon from our sect's treasury, specifically designed for armor penetration, just to break open a small opening.”

He withdrew his hand. “But we have to expand it regularly, otherwise it will heal itself.”

Lu Yan looked at his own reflection on the glass tube—his eyes covered in white silk, his black hair falling behind his back, reaching nearly to his waist. It was as if he were being watched by someone standing in another world.

“The stuff inside,” Fu Feng said, “has an extremely high melting point and can be used as an energy source. Once cooled, it becomes high-purity Spirit-Infused Iron.” At this point, his tone lifted slightly, carrying a trace of uncontainable joy. “The smithies in the entirety of Everspring City rely on it to keep running.”

Lu Yan listened, suddenly feeling a tightness in his throat. Looking at the golden liquid rising and falling inside the glass tube, he remembered that the Formation Sect had also guarded the Northern Border for so many years. In the past, this place had belonged to them.

If they had discovered this place ten years earlier—if this path had already been cleared when the Formation Sect was still around... would the outcome have been different? He didn't know. He could only stare at his reflection, lost in thought.

“Lu Yan? Lu Yan?” Fu Feng's voice drifted over from the side.

Lu Yan snapped out of it and realized that, at some point, he had stopped at the top of the stairs. Fu Feng was standing on the steps, having already walked down a few paces, looking back at him. “Your workplace is down below. Let's go down and take a look.”