Opening the Gates of the Demonic Realm
The moment the wall of water barring their path vanished, the expedition pressed forward without hesitation.
They cut down every monster that stood in their way, and whenever the road itself was blocked, the alchemists and mages cleared it. After several days of steady travel, they reached their destination.
A vast canyon split the land down the middle, hemmed in on both sides by sheer mountain ranges.
The moment the expedition arrived at the entrance to the Demonic Realm, they set to work building a fortress at the mouth of the gorge.
Naturally, the alchemists, mages, and spirit mages took the lead in construction.
"Noim, firm up the ground here."
"Should I use earth-attribute magic? Shock magic looks like it would work too."
"Stop deliberating and start building the walls."
"That's the alchemists' specialty."
While the warriors hauled boulders into place through sheer brute force, the others compacted the foundation and raised the ramparts with little more than a gesture.
They had been force-marching for days, yet their faces were bright with energy. Standing at last before the entrance to the Demonic Realm they had so longed to see was enough to conjure vitality out of thin air.
Theo, who had been helping me raise the walls through transmutation, asked,
Opening the gate won't be difficult, right?
"You place seven flowers on the altar and channel mana exactly as the instructions so helpfully describe. Anyone who fails that is a complete idiot."
And yet they designed it so it can never be opened from inside the Demonic Realm—and made sure no one could escape for five hundred years.
Which is exactly what made it so impressive.
Five hundred years wasn't some stray dog's name. Back in my old world, that was enough time for Joseon to be founded and well into its early-to-middle period.
The reason all these people who had spent their lives avoiding physical labor were suddenly bustling about so diligently was simple: finish the job fast, then get to studying the barrier.
I wrapped up my assigned section in short order and headed for the heart of the fortress.
There I spotted Casian deep in conversation with the Imperial Army commander, and called out to him.
"Your Highness the Third Prince! I'm heading out to set the traps!"
"Be careful."
I bowed my head in greeting toward Casian as he waved me off, then turned straight into the canyon.
The entrance to the Demonic Realm lay at the center of the gorge—and the way it barred all entry, as cleanly as if some colossal barrier had been erected there, drew a quiet murmur of admiration from me.
On the surface it looked like a simple sealing formation, but the deeper you dug into its structure, the more its complexity left ordinary barriers in the dust. I had been especially curious about how it sustained itself, and when I confirmed that it was drawing power from the ley lines flowing underground, a genuine sense of wonder settled over me.
"Ohh! To think a barrier this beautiful and fantastical even exists!"
"Is this the work of the Sage, the one who lives on only in the records?!"
"To witness traces of the Omnipotent One here—something no one has reached since the last Sage…!"
It partitioned space and prevented any living thing inside from getting out. It might have sounded simple, but considering it had kept the beasts sealed away for five hundred years, it was anything but.
While the specialist recording team from the Sage's Tower archived the barrier's structure, I examined the pattern engraved at the entrance.
"The sun, three moons, and a star."
Common symbols in alchemy.
"Hard to find symbols more useful than those."
In alchemy, celestial bodies were core symbols used constantly. The sun stood for perfection and immortality, the soul, consciousness. The moon meant change and flow, the body, receptivity. Stars represented the energy of the cosmos, fate, the sacred flame—it would have been stranger not to use them.
What mattered was the circular platform beneath those symbols.
A seven-pointed star was carved into its center in bas-relief. An altar sat at each vertex, and above each one a flower motif shimmered like a hologram.
I worked out the connections between the symbols and patterns without much trouble and moved on.
"The sun would govern the ritual consciousness. The moons represent the flesh of the sacrifice. And the stars…"
The energy to power the seven-pointed star—or the skeletal frame of the ritual itself, right?
"Exactly. That is a full-fledged transmutation circle packed with the fundamentals of alchemy."
In murim terms, it was like needing the Three Calamities Heart Method to dismantle a top-tier formation such as the Five Elements Myriad Transformations Array or the Celestial Dipper Formation.
I left the opening of the gate to the Sage's Tower.
Pulling my gaze from the barrier, I drew my minions out of my subspace pouch. They emerged loaded down with transmuted devices and, without waiting for orders, began scaling the cliff faces on their own. Dangerous work—but the minions paid it no mind, installing the devices one by one along the canyon walls.
Watching from a distance, Lowell approached.
"Preparing an interesting little trick, I see."
"It's surprisingly effective."
"You're the one in the city who knows beasts best, so I never doubted you."
Right. This man already knew I had been transmigrated.
Under that gaze full of trust, I made a slightly awkward face, cleared my throat lightly, and lit the Pioneer's Lantern.
There was no way I could activate that many devices one by one. I needed a remote trigger. I even factored in the canyon's mana currents so nothing would misfire—and once Lowell saw that, he stepped back.
Part of it was not wanting to interrupt a young genius's concentration. But more than that, as Branch Chief of the Sage's Tower, he had a duty to oversee the fortress still under construction. If even one person failed to keep a grip on the site, the alchemists would run wild like a runaway locomotive.
"This is where my ground-reinforcement device takes the stage!"
"Time to field-test the material-hardening spray!"
"A chance to deploy the intruder-repelling garden system in real combat! Scatter the seeds in front of the walls!"
Left unsupervised, there was no telling what they would cook up.
The fortress was going to play a critical role in the coming battle, so I hurried back to take charge of the site.
How much time passed after that?
In a single day, a fortress sealing the canyon mouth completely revealed its imposing form. If you broke down the labor that went into raising that massive stronghold by percentage, fully half of it had come from the hands of alchemists.
While the alchemists—who had just proven why they were called the makers of all things—lay sprawled and groaning, Casian surveyed the finished fortress with a gleam in his eye.
"Once we handle the wave, this wouldn't be half bad as a forward base."
It hadn't been intentional, but at this level of completion, calling it a temporary fort felt dishonest. Of course, that was a problem for later—assuming the fortress was still standing. I composed my expression and gave the signal.
The alchemists who received it began releasing the seal on the entrance to the Demonic Realm.
The intricate transmutation circle spun. The energy of the flowers set at the points of the seven-pointed star resonated. The moment the release conditions aligned, the separately moving formulae clicked into place as one, and the barrier spanning the canyon vanished like a mirage.
The entrance that had cut the Demonic Realm off from the outside world for five hundred years was open.
With the gate unsealed, the mystically perfect containment broke, and the strain on the barrier eased. Left alone, holes would have opened within a month and side paths would have formed—but with the main entrance open, that was no longer a concern.
At the same time, everyone inside the fortress felt it.
"They're coming."
Beasts were approaching from beyond the canyon.
The alchemists still near the entrance scrambled inside; the gates slammed shut, and the expedition moved to battle readiness.
"Artillery corps! Deploy the mana cannons from subspace!"
"Yes, sir!"
At Casian's command, the gunners activated their subspace bracelets. What emerged from each of those multi-thousand-gold transmuted devices was a massive mana cannon five meters long.
Kiiiiing.
Between two elongated rails, engraved runes flared to life and projected a field of blue energy. As the gunners worked the turrets, the railgun-like muzzles swung to cover the far end of the canyon and began concentrating power.
"Charge at eighty-eight percent!"
"Trajectory calculation error: zero point zero two percent!"
"Ready to fire!"
Having completed their loading with crisp efficiency, the gunners looked to Casian. The instant his order fell, fifty mana cannons would spit fire as one. Hundreds of expedition members would pour out ranged attacks, and some two thousand more would swing their weapons.
Bearing that heavy responsibility, Casian wore a confident smile.
"Just the right kind of weight."
A royal's duty was never light. Measured against everything resting on his shoulders, this much weight barely even counted as a warm-up.
Confirming the black tide revealing itself beyond the canyon, he raised his hand.
A roar of monstrous cries rolled toward them.
At the sight of beasts surging forward like a tidal wave, the expedition members' faces went pale. From the inner wall, though, I checked their numbers and snorted.
As I remembered it, the beasts coming down this route numbered roughly twenty thousand. Knowing that this was only a fraction of the wave that would have hit on the barrier-collapse route, they looked almost cute.
Compared to the alternative—the barrier finally cracking under strain, dozens of holes punching through, and hundreds to thousands of beasts pouring out of each one—this was the best possible outcome. Casian knew that too, which was why he had left the city's true fighting strength behind and put the pioneers out front to gain experience.
"All batteries—fire!"
KWAOOOOOM!
From atop the fortress walls, fifty lances of light streaked out in perfect lines. The beams, easily breaking the sound barrier, slammed into the black tide. The magic engraved on the warheads and the explosive payload packed inside chained together, and a magnificent series of detonations bloomed across the canyon.
I felt the vibration through my feet and let out a quiet note of admiration.
"As expected of Casian's custom mana cannons. Performance you can count on."
Seeing them in person, the raw power is ridiculous.
"He paid out of pocket to overhaul them into this."
Compared to standard mana cannons, he had pushed the output so far past the limit that their effective durability was only three to five shots. Component lifespan meant nothing. These things existed for moments exactly like this—an insane waste of money. The scariest part was that even after building them, Casian's personal fortune was still overflowing.
Remembering that someone with that kind of depth had volunteered to be my patron filled me with a solid sense of security.
When do the traps go off?
"Just a little longer."
I answered Theo with easy composure and kept my eyes on the canyon.
Thanks to the mana cannons Casian had prepared, the leading edge of the beast tide had been wiped clean. At the very least, close to ten thousand were dead. Half the force had effectively evaporated.
Even so, plenty remained. Losing the vanguard had blunted their breakthrough power, but most of the survivors were the kind that could fight at range—which made them a real problem. We were outnumbered too. If we fought like this, the fortress wouldn't last.
Which was why the expedition's top priority was holding out until the mana cannons finished cooling and the second barrage could begin.
"Archers, ready to fire!"
"Mages, begin your chants as planned!"
It wouldn't be easy. Fight like this and a great many people would die. That was exactly why I had sent the minions to install the devices throughout the canyon.
"They're walking right into it. Almost makes the prep worth it."
It's finally starting!
"Kyuuut!"
As if my words had been the signal, Theo and the spirit bodies lit up with excitement.
I calculated the positions of the installed devices against the beasts' locations, drew out the Pioneer's Lantern, and pulled the trigger.
At once, hundreds of devices activated, and the canyon vanished under a blanket of fog. Not ordinary fog—cold so absolute it froze everything it touched.
Crrrk-crrrk-crack.
This wasn't cold from mere low temperature. An ice mist born from mana woven together with the effects of cold-aspected materials froze even the beasts solid, locking down their ability to attack at range.
Watching them stand there with frost coating their hides, forced to stare helplessly while the mana cannons recharged, I let a crooked grin spread across my face.
Surprise~