Max
The next day started much like the last, with him waking up well rested. The exhaustion from the grind had been burned out of his system overnight, leaving behind a clear, humming sharpness.
He moved through his morning routine at an unhurried pace — washed up, dressed, headed down to the kitchens for a proper breakfast. The mess hall was quieter at this hour, mostly off-shift guards and the occasional bleary-eyed clerk nursing something hot. Max ate without rushing, working through a plate of eggs and dense brown bread while mentally sketching out the day's priorities.
By the time he returned to the suite, Kairu was already awake and stationed at the desk, a careful, focused B currently taking shape in blue gel on the parchment in front of him.
Max set his tea down and turned to the supplies he'd hauled back from the market district the previous afternoon. A light pulse of magic sent the bulk of it away; the magic circle bloomed under his hand, swallowed the provisions, and faded without fanfare. Stocked for the foreseeable future. Good.
That done, he reached back into his storage and pulled out the one item he had been genuinely curious about since yesterday: the cloth-wrapped bundle from Todo's forge.
He set it on the desk beside Kairu's alphabet work and unwrapped it, revealing the slender, finely-crafted magic sword beneath. Even unsheathed and still, the blade had a particular quality to it — that faint, settled hum only a magical item produced.
"Hey, Kairu," Max said.
The slime turned, leaving the B half-finished.
"I need you to eat this and analyse the composition — how the magic is set into the steel, and whether we can replicate the technique ourselves."
Kairu let out an eager Ki! and bounded over without hesitation, engulfing the blade in one smooth motion. His translucent blue mass flared with a soft, distinct azure light, pulsing rhythmically as the sword dissolved. Max watched the glow for a moment, eyes narrowing in quiet interest, then pulled out a fresh sheet of parchment.
That process would take however long it took. In the meantime, he had a ring to test and a bracelet to design.
-◈ -
Kairu
He did not think in words.
He thought in shapes. Pressures. The specific electrical texture of things he had taken into himself, the residual warmth of intention baked into steel by hands that had known what they were doing.
The sword felt wrong the moment it entered him.
Not dangerous-wrong, just other. The outer layer tasted like metals he recognised from the blades he had eaten yesterday — familiar traces, scattered through the structure in thin veins. But the weight of the whole was different. It did not sit in him like simple material. It sat closer to the way his own bio-weapons did when he shaped them: dense, responsive, ready to move.
As it dissolved from tip to hilt, the texture shifted. The top half went down as clean material — lines and channels, harmless now that they were no longer holding anything. It was only when the base began to melt that Kairu felt it: a small, compressed pulse at the root of the weapon.
Not a strike. Not a command.
Just leftover magic, trapped in the last intact knot of the pathway.
The pulse fluttered through his mass like a dying heartbeat, bled out, and was gone. He filed the shape of it away with the rest — the strange, half-familiar metal and the way the weight of the sword had felt closer to living construction than dead steel.
He was still filing when the other thing surfaced.
It had been sitting in him since the dive — since Master had pressed the small glass shape against his membrane and the liquid had crossed into him. Kairu had been too occupied with The Hunger below to look at it properly then. But now the sword's structure was giving him a way to think about deliberate construction, magic laid in ratios that meant something, and he turned that new lens inward and found the liquid waiting.
It had a shape too. More complicated. Layered and suspended, biological and magical components coiled around each other in a specific tension that held as long as nothing disturbed the balance. Kairu remembered what it had done when it moved through him — the way his own thinking had gone sharp and bright, problems that had been dense suddenly thin enough to pass through. He remembered it the way he remembered everything useful: as a texture he wanted to feel again.
And now he wanted to feel it again.
That was enough.
The Hunger still pressed at him when they went below — patient, directionless, the oldest kind of wanting, the kind that had existed before anything had a name. But the first time Kairu had felt it, it had been reaching for Master. That was enough to know what it was. That was enough to know it would not have him.
Before the sword finished dissolving, Kairu was already sorting. He moved through what he had accumulated since the dive — the organic residue of dozens of species layered through his mass, trace minerals and compounds from everything his Devourer had broken down, the faint magical signatures of floor creatures whose bodies carried sensory sharpness like a habit, an inheritance. He had always had these things. He had never before thought to arrange them.
The sword had taught him arrangement.
The ratios were wrong the first time — he felt it immediately, a faint trembling in the suspension that meant it would fall apart instead of hold. Wrong the second time too, a much more violent instability. Leaving the raw monster ingredients to touch directly made them volatile; the magical component bled into the biological, swelling with a sharp, contained pressure that threatened to rupture and go boom inside him.
The third time, he changed the structure. He didn't just mix the stolen parts; he used himself. He injected a steady flow of his own magic and a thin vein of his own liquid mass directly into the centre of the formula. It felt right instantly. His own matter acted as the binder, smoothing the friction between the raw ingredients and locking them in place. The compound settled into perfect stillness. Kairu held it and felt it hold.
He drew a small portion of his own mass outward, shaped it into the narrow glass form he had seen in Master's supplies and let the liquid fill it. Pale blue-green. Faintly luminescent. Not quite the color of the original, but close enough to carry the same weight when he looked at it.
He turned to face Master.
Master's head was down, pen moving. Kairu watched the movement for a moment — the precision of it, the way it committed shapes to parchment with a certainty Kairu did not yet have.
He needed to give Master a shape.
The alphabet chart was still spread across the desk, and Kairu looked at it the way he looked at everything: not as symbols but as objects, each letter a distinct pressure, a geometry. Some he knew well now — they had weight, context, the accumulated texture of seeing them used and understanding what they did. Others existed only as outlines. Shapes he could reproduce without understanding what they pulled toward.
And with what he wanted to say clear in his mind, he used his pseudopod.
H.
He pressed it into the parchment. Looked at it. The weight was right.
e.
Smaller. He had seen this shape in two forms and they felt like different objects entirely. He chose one and was not certain.
a.
He pressed it and paused. The next letter was at the edge of what he carried — the shape was there but nothing behind it, no context to anchor it into meaning.
He pressed it anyway.
F?
And stopped.
The rest of the word was gone. Not forgotten — never held. Kairu looked at what he had made: HeaF
The gap between what he meant and what he could build sat in him the way the wrong ratios had sat in him. A wrongness. A thing that did not hold.
He raised his free pseudopod and tapped the uppermost curve of his own mass—the place where Master focuses. Then he let a thin stream of clear water fall from his other side in a deliberate arc onto the desk. He held the gesture. Held the glass. Looked at Master.
Head. Liquid. This. Same.
-◈ -
Max
He had just turned back to his designs when movement at the edge of his vision pulled him up.
He turned to find Kairu holding a small, slime-glass of faintly glowing liquid in one pseudopod, a stream of water arcing deliberately from the other, while repeatedly tapping the top of his own gelatinous head and pointing at four letters pressed into the corner of the parchment.
HeaF
Max stared at the letters for a moment, then at the glass, then at Kairu's frantic tapping.
HeaF... does he mean Head?
His eyes dropped to the glass. The color and faint glow gave it away even before he lifted it.
Mind potion.
Max reached out slowly and took the glass from Kairu's pseudopod, bringing it close and inhaling. The smell hit him immediately — the same clean, faintly mineral sharpness as the High Mind Potion from the dive, with something underneath that was slightly different. Warmer, maybe. A trace of Kairu's own organic makeup that the original hadn't carried.
He looked at Kairu. Then at the spot on the desk where the sword had been before it vanished, Kairu's mass now settled back to its usual hue.
The sword. He must have used the sword's analysis as a framework, stabilized it with his own mass, and rebuilt the potion from memory.
Max set the glass down carefully and studied his familiar for a long moment.
Kairu held very still, the way he did when he was waiting for a verdict.
"You worked this out yourself," Max said. It wasn't a question.
Ki. Quiet. Certain.
Max stared at him in surprise, a massive swell of joy blooming in his chest. It's akin to what Rimuru did, he thought. When he was imprisoned in Dwargon, Rimuru had consumed raw Hipokute herbs and magic ore, analyzing them internally to synthesize high-grade healing potions from scratch. Seeing Kairu actively taking after the iconic slime he was named after... it made Max impossibly proud.
He picked the glass back up while reaching into his storage bag and pulled out the original High Mind Potion, holding them side by side. The color was slightly off—Kairu's version ran bluer—and the luminescence had a different quality. But the structural smell was close. Closer than it had any right to be.
He set the original down and, after a brief pause, drank Kairu's.
The effect came in about thirty seconds. Not identical — there was a warmth to it the original hadn't had, a slightly different texture to the cognitive sharpening, as though the enhancement had a biological dimension layered beneath the magical one. But it worked.
His thoughts settled into that familiar crystalline clarity, the bracelet schematic in front of him suddenly legible in three dimensions where it had been flat before and his magic reserves replenished with a clean, immediate rush — not quite at the level of the High Mind Potion, but should be comfortably comparable to a standard one.
Max exhaled slowly, his mind already turning over the implications of what had just happened.
After a moment, he reached down and gave Kairu a firm pat, squishing him with affection.
"Outstanding, buddy," Max said with a proud smile.
Ki-ki. Kairu jiggled, proud, satisfied, and as the moment passed, went back to his letters.
-◈ -
Max let the last traces of the potion's clarity settle and, for once, didn't immediately reach for more work.
Instead, he leaned back in his chair, eyes resting on the empty slime-glass and the faint blue stain it had left on the wood.
He pegged it closer to a standard mind potion. Not quite High-tier yet, but should be better than anything a normal rookie could afford to chug between floors. And this was just Kairu's first batch.
His brain, now helpfully overclocked, did exactly what it always did: ran the numbers, then ran the roadmap.
On the money side, the possibilities stacked up fast. A solo stall in the commercial district. A quiet bulk deal with the Guild to fold the lower-grade version into newbie kits. A more surgical collaboration with Airmid to push a refined variant through the clinic. A future tie-in with Raymond or even a formal Familia shop under Freya's banner once he had more product lines—rings, bracelets, and whatever he cooked up next.
But business was only one side on the board.
He already had enough on his plate: the rings, the bracelet, the Uber service, and the rest of the logistics.
Then there were the things he wanted to learn: Thought Projection, Heavenly Body Magic. Especially Heavenly Body Magic. It was stupidly tempting.
Meteor, absolute acceleration, localized movement cheats that would turn his close-quarters into something only gods and monsters could track. But going down that rabbit hole right now meant rewiring how he fought from the ground up. New muscle memory. New collision math. New collateral to account for.
He already felt like he was juggling a small company in his own head. Adding "rewrite the laws of how fast I can move" to this week's list was a good way to break something—probably himself.
Thought Projection, on the other hand, sat dead center in everything he wanted to do.
And he finally had more than just anime memory to work with.
The War Shadows from yesterday flickered through his mind—those insubstantial bodies, the way their forms blurred at the edges, the way they existed half a step sideways from others. They weren't spellwork from his world, but the principle was the same: a presence that was there enough to threaten and act, but not so there that destroying it meant anything permanent.
Mass without meat. Pressure without organs.
Watching them had given him an anchor—how weight and intent could be faked, how something unreal could still trip every instinct that screamed danger in a trained adventurer's body. He had a much clearer sense now of what a "fake" body needed to feel like to pass casual inspection.
He still had no idea how cleanly his Ars Magna would interpret that understanding. Whether it would give him something sleek and efficient, or glitch out into mana-wasting garbage. But for the first time since seeing Jellal's Thought Projection in the anime, he felt like he had enough data to at least make a serious attempt instead of flailing in the dark.
With that clarity, he straightened in his chair and turned to the wobbling copy sitting at the edge of the desk.
"Alright, Clone-Kairu, I need a piece of you to see if the battery theory actually works." Max said.
The clone extruded a small, marble-sized blob of its own mass, severing it with a wet squelch.
Max caught the cool lump in his palm and rolled it once between his fingers, testing the consistency. Kairu's gel was dense now—which should also translate to better storage capacity. Good. This should be able to handle it.
He drew a slow breath, closed his eyes, and channeled Hadō #1: Shō into it. Not the chant, just the pure power—a simple, concussive push, short range, single vector, no elemental magic. He let the intent build in his forearm, then pressed it down directly into the slime's mass.
The blue gel brightened with a sharp flash of pale light, like someone had turned a torch on inside it. For a heartbeat it glowed, then the color sank back to its usual shade, the surface going completely still again.
The spell sat there. Contained. Waiting.
Max opened his eyes.
He raised his free hand and wove a small, shimmering barrier into existence a few feet away—nothing fancy, just a flat, translucent pane anchored to the air. A target.
He lifted the charged lump of slime, sighted down his arm at the barrier, and sent a small, wireless pulse of triggering intent into the gel.
Bang.
The Shō snapped loose, but not where he wanted it. The concussive bolt punched sideways out of the slime's left flank, missed the barrier entirely, and splattered harmlessly against the floor.
Max lowered his hand and looked down at the gel in his palm, his lips pressing into a thin line.
Of course. Without a rigid structure to guide the exit location, the magic just takes the path of least resistance through the mass. It has no idea where it's supposed to fire from.
So he needed a barrel.
He reached over to the side of the desk and picked up one of the rings Kairu had made earlier. The setting was a neat, circular cavity cut directly into the band, waiting to be filled.
Max pressed the charged lump of slime into the ring's empty heart. The gel flowed smoothly into the cavity, conforming to the metal borders until the surface was flush—a perfect blue core held in place by grey steel.
This time, he took a moment to line the shot up properly.
He leveled the ring toward the barrier, turning his wrist so the engraved face pointed directly at his target, and pushed a fresh pulse of triggering intent into the slime.
VWOOM.
A perfect, compressed blast of concussive force erupted straight out of the ring's face, crossed the room in a clean line, and slammed squarely into the test barrier. The construct shattered into motes of light, dissipating in a neat, satisfying spray.
Max let his arm drop and turned the ring over in his fingers slowly, studying it.
The gel was the battery. The metal framework was the barrel. The engravings were the firing solution—the part that told the spell where and how to leave.
Making a full circuit.
And it had worked, cleanly, on the first structured test.
He set the ring down on the desk and let himself sit with the implications for a few seconds.
Then a different thought surfaced, cutting across his design calculus entirely.
If Ars Magna operated on intent and a clear understanding of a phenomenon, and Kairu possessed Ars Magna Lesser as a direct offshoot of his own system—why was he thinking of his familiar purely as a component rather than a caster in his own right?
"Hey, Kairu," Max said, finally breaking his concentration as if he couldn't help it. "I think you can cast Kidō."
Ki? The main slime tilted, a metaphorical question mark hovering above his head.
"It's not about words or incantation. It's about intent—holding the image of the result clearly in your mind." Max tapped the center of his own head. "We're starting with Shō. Imagine pushing something away from you without touching it. Just the force of it, the direction, the result. Try it on the door."
He sat back and crossed his arms.
Kairu turned to face the heavy door. The slime scrunched his mass together, light flaring brightly in his body as he concentrated. He drew back his pseudopod, like a fist cocking, and thrust it forward.
A heavy THUD echoed through the suite as an unseen force slammed into the door, rattling it hard against its reinforced hinges.
Ki-ki-ki! Kairu launched off the desk, bouncing off the ceiling and landing back in a triumphant, joyous puddle.
Max sat forward, genuinely delighted. That had worked faster than expected—and cleaner. No misfire, no sideways discharge. Whatever Kairu's cognition had become since the Level Up, it was operating with a precision that still occasionally caught him off guard.
"We'll build up from there," Max said, watching his familiar vibrate with barely-contained pride. "In fact, let's just knock it all out right now."
The rest of the day passed in a hyper-focused blur.
Max abandoned the desk work entirely, dedicating the afternoon to walking Kairu through every Kidō spell up to the 30s. The slime's Ars Magna: Lesser proved terrifyingly efficient. As long as Max provided the clear conceptual framework and the intent, Kairu could lock the spell into his head and reproduce it.
Once Kairu had the basics down, they moved back to the hardware. They spent hours mass-producing the ring batteries, filling the hollow bands with dense, charged gel. Max pumped the heavy artillery—the Level 60 spells—into the rings himself, using full incantations to ensure maximum stability and yield.
By evening, they had three distinct sets of weaponized jewelry laid out on the desk.
The defensive Tozansho (Inverse Mountain Crystal) rings were left uncolored, relying on the natural grey of the steel. The offensive Raikōhō (Thunder Roar Cannon) rings were etched with deep red enameling along the matrices. And the binding Rikujōkōrō (Six Rods of Light Prison) rings were marked with bright green.
Color-coded, single-use, high-tier magic. They obviously needed to be field-tested in the Dungeon to ensure the metal didn't melt under combat stress, but the foundational tech was sound.
When the next morning rolled around, they split their focus.
Max had spent an hour explaining the remaining phonetic rules of the alphabet and the structure of basic numbers to Kairu. Armed with this new, monumental puzzle, the main slime happily retreated to the corner of the desk to practice, his gelatinous mass twitching with absolute concentration as he tried to reconcile the shapes with their sounds.
With his familiar occupied, Max finally turned his attention to his Thought Projection problem.
-◈ -
The framework was in his mind, but conceptual reconstruction was infuriating. Max remembered what Jellal's spell did, but translating a narrative memory into a working magical blueprint was a nightmare. He didn't need to make the projection physically real yet—just perceptually present—but projecting a psychic copy of his own magical signature outward required a level of focus he wasn't used to.
His early attempts were embarrassing. He pushed his mana outward, but without a precise mental image serving as a rigid template, the result was a shapeless, burgundy-glowing blob of magical exhaust that hung in the air for two seconds before dissipating.
"Okay, refine it," Max grunted, wiping sweat from his brow.
He pushed harder, locking down his focal control. This time, the projection flickered into existence—a perfect, static copy of himself standing by the door. But the moment Max blinked, the cognitive divide snapped. The illusion sputtered and dissolved like a blown fuse.
He spent the next three hours hitting the mental training wall.
It wasn't a magic problem; it was a processing bottleneck. He sat cross-legged on the floor, utilizing the compartmentalization logic he knew from Naruto's Shadow Clones mixed with deep-focus techniques. He had to learn passive body anchoring—trusting his physical body to keep breathing and balancing on autopilot while his primary consciousness rode the projection.
By early afternoon, he managed to hold a sustained, static projection of himself across the room. He could move it like a puppet from a third-person perspective.
Then came the sensory whiplash.
Determined to make the connection two-way, Max forced a sensory bridge to form, commanding the projection's "ears" to feed data back to him.
BZZZT—
The dual influx of sound hit him like a physical blow. He was suddenly hearing Kairu's quiet squelching from across the room at the exact same moment he was hearing his own breathing in stereo. The terrifying disconnect of processing two distinct acoustic locations simultaneously sent a violent wave of vertigo straight into his brain. Max collapsed, dry-heaving onto the marble floor.
"Right," Max wheezed, rubbing his throbbing temples. "Brain wasn't meant for multi-boxing. Noted."
He forced himself back up. If sensory feedback was going to make him vomit, he needed to outsource the mental load.
"Independent Action," Max muttered, calling up his magic. "Complex Protocol."
He began weaving the logic directly into the tether, handing over the crushing strain of maintaining the projection to his magic.
Instantly, it felt like closing fifty tabs on an overworked internet browser. The immense, splitting weight on Max's mind evaporated. He let out a long, shuddering gasp of relief as his brain finally caught up to reality. He could still monitor the projection passively, but his magic was doing the heavy lifting.
With the stability problem solved, Max hit his next hurdle: visual variety.
His goal wasn't just to project his own face. He wanted the Uber-persona to look like Itachi, or Gojo, or Rimuru. But when he tried to force the projection to adopt a shape different from himself, the spell rigidly refused to compile. Thought Projection inherently demanded a true psychic copy of the caster.
Max frowned at the stubbornly blue-haired hologram.
Then, he sighed, closed his eyes, and activated his transformation.
His body shrank, shifting smoothly into the familiar form of Rimuru. He stood there for a moment, letting the new magical signature settle, and then cast Thought Projection again.
Across the room, a perfect, stable hologram of Rimuru materialized.
Max stared at it, then dropped his transformation, returning to his normal look. The Rimuru projection remained, perfectly sustained by Independent Action.
"...That is honestly stupid," Max muttered, a slow grin spreading across his face.
The spell was rigid—it would only copy what he currently was. But because he could literally become anyone, he could just transform, cast the projection, lock it in place with his skill, and then transform back. It was an easily exploitable loophole, and he was absolutely thrilled to abuse it.
By the time this realization came, he was magically and mentally spent, but the core foundation was finished.
He just needed the hardware. Aka the body.
"Hey, Kairu," Max called out, dropping heavily into his chair.
The slime paused his intense study of the number 9 and squelched over, waiting attentively.
"I need you to act as the physical body for these projections," Max said, gesturing to the Rimuru hologram. "For them to hold up against anything they'd meet in the dungeon, they can't feel like water balloons. They need to feel real—skin tension, the right density, the right weight."
Kairu paused and wiggled uncertainly. Mimicking shapes was one thing. Replicating the specific biological properties of a human body was a different category of problem entirely.
Max pointed to Kairu. "Use Devourer on the monster corpses from our last dive. You still have them, right?"
Kairu gave a slow, affirming jiggle.
"Break down the organic matter and synthesize the muscle fiber and bone density. You can use the physical frame of a Minotaur for the heavy musculature and the skull density of a Silverback as a starting point. Or, if it's easier, just take the structural mould of my own body and scale it from there. Your gel acts as the binding agent throughout."
It was a deeply morbid concept. Kairu, however, did not possess human squeamishness. A task was a task, and building a body was just another form of progress.
With an eager squelch, he extruded a series of thick pseudopods, anchoring himself to the floor as his mass began to churn. The faint, deeply unsettling sound of organic matter being rapidly dissolved, sorted, and restructured began echoing inside him.
Max leaned back in his chair, still exhausted, but also satisfied.
He had a pocket full of weaponized rings, a working projection framework, and an automated flesh-suit currently under construction in the center of his room.
Tomorrow, they were going back to the Dungeon to test it all. He let out a long breath, a satisfied smirk settling on his face.
Hope you are ready for what's to come...
--> Devil in a Dungeon <--
AN:
Another 2 days gone with lots of magic practice. Kido, Rings, Thought Projection and Kairu eating a magic sword and producing a standard Magic potion. Out of all the options for potions, which option did you like? Airmid, Guild, Own Store or Freya Familia store?
We will get into stress testing of the rings and some other stuff in the next chapter. Followed by the big day in the dungeon.
And as always, don't forget to share your thoughts on the story in a review/comment.
If you'd like to read 8 chapters ahead(around 40k words), support my work, or commission a story idea, visit p.a.t.r.e.o.n.c.o.m/b3smash.
Please note that the chapters are early access only, they will be eventually released here as well.
Next update will be on Tuesday.
Ben, Out.
Disclaimer: I don't own anything.