Boom!

The heavy door slammed shut behind us. It was nearly a meter thick, making Naneow hesitate a moment to open it. Beyond lay a vast hall, dwarfing the cramped cave before. The air was clean, so much that it was hard to believe we were underground. There were neither lanterns nor glowstones, yet the entire chamber glowed with steady, comfortable light. Every corner was illuminated, perfectly regulated by high magic.

Straight ahead, a large table stood on display. I studied it as I walked with Naneow. It was plain white marble, with its four pillars bare of ornament.

On top of that broad surface lay only two tiny reagent bottles and a slip of paper that read: Sprinkle this!

"Is this from the massive duke? What a weird taste."

The note’s corners were marked with four hearts, all blackened in. Opposite the table hovered a great ring of fire. Naneow eyed the magic circle beneath it.

"Typical reactive portal..."

Swish.

She shook a vial, bone-dry. "This one’s empty."

"..."

After seeing the two empty bottles and the black-hearted note, my head started to ache.

"Waiter, another bottle, please?" Naneow muttered, as if she were telling a 300-year-old joke.

My headache grew.

"..."

The silence grew longer. We searched the table, the floor, every angle. Nothing but those two vials.

Neigh!

Bored with our inaction, Miyu leaped straight through the burning ring.

"Nothing’s happening."

"Haaaah..."

Naneow exhaled in despair as if it were obvious. Even when Miyu bounded back and forth dozens of times, the result was the same.

Clunk.

I tried as well—reaching, stepping, even thrusting my head in. No use.

Naneow covered her face with both hands and groaned. "Don’t waste your strength. Force won’t change anything..."

"So the marquis sprinkled his vial and passed through?"

She nodded. "Exactly. The trail leads straight across. That bastard, couldn’t even leave half for the next poor fool?"

Which next poor fool she meant didn’t matter. Of course, the marquis had no such loyalty. We should’ve been grateful he hadn’t left blades swinging behind.

"Is the reagent truly necessary?"

Naneow lowered her hands, expression grim. "Unfortunately. The linked substance is the key. Only with it can the portal stabilize. Even someone who can tear space wouldn’t bypass it. We’re not trapped, but..."

Her tone carried little hope.

I thought for a moment. "There has to be another way down. We’ll find it."

"...?"

Her eyes widened.

I went on explaining, "Think of the plains. Your knowledge about chupacabras hating fern-fruit was essential to pass. In the volcano, we had to notice the heat lessened toward the peak, and then have the courage to leap into molten rock. Each floor has a key. This one will too."

Maybe I was just talking big. However, certainty could also be a trap. The belief that reactive portals always required a reagent could blind us.

Naneow blinked, then lowered her head, only to throw it back and laugh loud and hard. "Kh... kukuku... pffft, hahaha!"

"What is it?"

Her reaction caught me off guard.

She said, voice still thick with laughter, "Don’t try to cheer me up like that. You’ll kill me. Ha... fine. You’re right. We’ll try. I had ideas already. Look around, this hall’s enormous, isn’t it?"

When she finally calmed, her tone softened oddly. Leaving the table and portal behind, she surveyed the surroundings. The hall was colossal. Aside from the straight path from the iron gate to the central table, the rest of the space was packed with benches, racks, and storage shelves.

"Wow..." She walked among them, voice full of awe. "With this stockpile you could make gold underfoot. Premium solvents, catalysts with surgical selectivity, even rare separation agents..."

I stayed close, inspecting the nearest racks. It was broader than the ancestral vault beneath Grassmere. Where that vault had held relics and engines, this was a laboratory. Endless glassware, flasks in every hue and clarity, and strange ingredients lined up with exacting care. It was a massive alchemical workshop.

There weren’t just liquids; transparent tubes held flames of blue and white. There were ancient rocks, exotic blossoms sprouting in shallow water, and even plants glowing faintly in their jars.

"So... there really is no such thing as just die here." Naneow’s voice carried from a few steps away. Relaxed, almost cheerful. "But we still have a problem. What exactly are we supposed to make?"

Without knowing which reagent to brew, everything was useless.

"Earlier you said there’d be a way," she teased. "That was just hot air?"

"I meant..."

"Yeah, I’ll probably have a way."

Across the storage bay, Naneow gave me a teasing look, and pulled a slender black rod from her robes. It was so thin, it could almost be mistaken for a needle, with a tiny bead attached to the tip.

"Hand me the vial."

I passed her the empty reagent bottle without hesitation.

Creak.

She scraped the inside of the bottle with the delicate rod. At last, a droplet of transparent liquid clung to the bead, barely enough to count as a single drop.

"Phew... saved. This should be enough. I don’t know if this place is a temple of alchemy or what, but it’s equipped with a first-rate composition analyzer. That thing right in front of you, that’s the analyzer."

She kept her grip on the needle-like rod as she explained carefully. 𝑓𝘳𝑒𝑒𝓌𝘦𝘣𝘯ℴ𝑣𝘦𝑙.𝘤𝑜𝑚

"It’s not just the analyzer. There’s every kind of device here. Perfectly calibrated protective gear, oxidation meters, spectrophotometers, adsorption analyzers, separate extractors for solids, solvents, and soil. Even a micro-structure slicer, a thin-film deposition machine, an ultrasonic disruptor, and a liquid contact-angle measuring device. There was a differential scanning calorimeter, capable of both room and cryogenic-temperature analysis. A microbial incubator and the analyzer we’re using now are commonplace, but there were items even I didn’t recognize."

"I can tell that’s impressive...."

"Among the tower masters, only a handful could rival this level of expertise in alchemy."

"You mean the Azure tower masters?"

"Exactly. Bring it over to the table."

Clack.

Wooong...

The black machine, threaded with vein-like cables, began to hum on its own. Green and red lights blinked in succession as I stared, fascinated by the contraption.

"It’ll take twenty minutes. Wait a bit." Naneow straightened, pressing a hand to her back, and tilted her head to the ceiling. "This place is astounding. Honestly, disturbingly so. I’m Naneow Tropin, after all. I call myself the shadow behind the world. If even I find this unsettling..."

Her eyes stayed fixed upward, then carefully traced along the domed ceiling and down the walls.

I realized she wasn’t simply stretching. "Unsettling...?"

I followed her gaze. The walls and ceiling were coated in cold metal, carved with repeating patterns. At the center was a blue dodecagon, its corners flanked by pairs of white blossoms. Encircling it were twenty-four indented golden stars. Between them, countless geometric lines overlapped, shifting ever so slightly into new shapes. The enormous wall was covered in dense anti-magic patterns, far more intricate than those etched onto Isabelle Simone’s armor.

Of course, I couldn’t begin to interpret their meaning.

"Orchid, Papua blossoms, and an Abract expansion. They’ve mapped out polytopes with symmetry, projected step by step into two dimensions. It’s a perfect net."

"A net?"

"Yeah. In short, it’s a top-class shock absorber. Even if some impossible force struck the ground directly, it would disperse the impact."

"..."

"It’s been fortified to the extreme. No matter what happens outside, breaking through this place would be nearly impossible. And that’s not even counting the imperial barrier."

"Even something like a war?"

Naneow gave a sharp laugh. "A mere war? No. What kind of human power could compare? Do you realize how deep underground we are? This... I don’t know. There are supplies meant as food substitutes, too. Liquids that keep you full all day with a single drop. This place is absurdly well-prepared for long-term survival."

"..."

What if it was more than war? One thought immediately leaped to mind. The descent of the Demon Kings, ten years from now. Were they preparing for that here? No, perhaps it was only natural.

It was the Empire that prepared for war. The anti-war faction had also been assassinated by them. Ultimately, the Empire’s war would end with the Demon King’s descent. Cause and consequence, indistinguishable.

The Empire is summoning the Demon Kings...?

I remembered what Aezar the stag had told me. The Demon Kings would arrive, nourished by human blood and screams. And when they descended, humanity would come to an end. Nevertheless, would that still be the case in this underground refuge, far deeper and safer than the so-called Path of Freedom?

Another thought struck me. The Demon Kings would be slain by the Heroes—beaten and torn apart. Then, the world of mankind would return, more ruthless than ever. Those who were chosen and took refuge here would emerge once the age of Heroes began, free to act without restraint. In a world darker and more lawless than ever.

With the Demon Realm opened, monsters would flood the surface. They’d prey more plentiful and varied than ever before, reveling in overwhelming indulgence like an all-consuming tidal wave.

Whoever planned this design and hid here was looking twenty years into the future.

Could it be that the very idea of the Heroes—

Clatter.

I was about to voice my suspicion to Naneow when the machine, which had been whirring for some time, came to a halt.

"Good. The analysis is done, but... hmm."

Her face darkened.

"What’s wrong?"

"This... ugh. This is why I hate egotistical humans. The reagent has the creator’s signature embedded in it."

"A signature?"

"You enchant a specific material, then feed it into the analyzer. Instead of showing its real properties, it displays a pattern of your choosing."

"Is that easy to do?"

Naneow shook her head. "It’s insane, perverse, an utterly wasteful act that takes ridiculous effort. But sometimes, just to prove they can, they’ll do it with an easy material. I know about two hundred and sixty signature-capable ingredients. If we’re unlucky, this could take a whole day to—huh? What are you doing?"

"I think I know what it is."