The next second, the artifact activated.
A projection appeared.
But it wasn't just an illusion.
A new hologram formed, overlaying Tony's existing technological system—two different frameworks, science and sorcery, clashing… and then, strangely, aligning.
The armor design reappeared.
Almost the same.
But with significant changes.
The energy flow was reorganized.
Heat distribution was restructured.
And the propulsion core… was completely redesigned.
Kuro spoke while pointing at different parts of the hologram.
"Your repulsor output is too aggressive in the initial thrust phase," he said calmly. "Energy is wasted as heat before it can be fully converted into thrust."
He shifted the design layer.
"If you split the flow into a two-stage process—compression and release—you can achieve the same thrust… with significantly lower heat buildup."
Another motion.
The internal structure changed.
"Add a secondary cooling channel around the plasma core. Not to cool it… but to stabilize energy fluctuations."
He glanced at Tony briefly.
"The point isn't to suppress heat."
A short pause.
"…it's to control it."
Kuro lowered his hand.
The hologram continued running.
Simulations showed a clear increase in efficiency.
"…With this, you can increase output without risking system overheating," he continued casually. "And the response… should be smoother."
Silence.
Tony didn't move.
Didn't speak.
His eyes were locked onto the hologram.
Layer after layer of data—both from his own system and Kuro's projection—merged, complementing each other.
A few seconds passed.
Long enough.
"…JARVIS."
His voice was quiet.
"Yes, Sir."
"Compare my design with… whatever this is."
A brief silence.
Then Tony stepped closer.
Closer.
His eyes narrowed.
Not out of suspicion.
But focus.
"…Okay," he muttered softly. "That's not a coincidence."
His hands moved quickly, sliding the hologram, enlarging the sections Kuro had modified.
"Dual-phase compression… flow stabilization… secondary cooling as a regulator, not a heat dump…"
He stopped.
Turned to Kuro.
His expression changed.
Not casual anymore.
Not joking either.
"…You didn't even look at the code."
A pause.
"…And yet you dissected my system like it was your own."
He exhaled slowly.
Then—his smile returned.
But this time, it was different.
Sharper.
More… alive.
"…Okay, 'desert wizard,'" he said quietly. "Now I'm interested."
He crossed his arms.
Looked directly at Kuro.
"Because there are two possibilities here."
One finger raised.
"First—you're a genius."
A second finger.
"Second—you're not human."
A pause.
A faint smile.
"…And for some reason," he continued casually, "…I think the answer is both."
He turned back toward the hologram.
"…We're using this."
Then, without looking back—
"But don't get me wrong."
His tone lightened again.
"I'm still going to claim this as my idea."
Kuro shrugged lightly.
"I'm not a genius," he replied casually. "And this… isn't my idea either."
He didn't elaborate further.
As if it wasn't worth explaining.
Meanwhile—a calm, synthetic voice filled the room again.
"Sir," JARVIS said, "comparative analysis indicates a 37.6% increase in energy efficiency and a 42% reduction in heat accumulation during the initial thrust phase."
A brief pause.
"However, I am also detecting an energy anomaly not registered in the system database."
The hologram shifted, as if highlighting something.
The focus moved—to the golden cube on the table.
"That energy is stable, clean, and shows no known chemical or nuclear reaction patterns," JARVIS continued. "Its source is identified as that object."
A thin silence settled over the room.
Kuro glanced briefly at the cube, then returned to his usual relaxed posture.
"Yes," he said lightly. "That's magic energy."
He picked up his drink again, slowly turning the bottle before taking a small sip.
"If you want to understand it… magic isn't that different from technology," he continued. "It still needs a 'fuel source.'"
He raised the bottle slightly, as if giving a simple example.
"A vehicle needs gasoline. Humans need energy from food."
A brief pause.
"Magic is the same."
Kuro's gaze returned to Tony Stark.
"And like all systems…"
His tone remained casual.
"…there is always a drawback."
He leaned slightly against the workbench.
"The difference is only one thing."
A faint smile appeared.
"Technology tries to remove limits."
"…Magic?"
He shrugged.
"We simply learn to live with them."
Tony didn't answer immediately.
His eyes stayed on the golden cube—then the hologram—then back to Kuro.
"…Magic energy," Tony Stark muttered softly.
He exhaled a short breath, half-laughing.
"Great. Sure. Why not just make the world even weirder."
A pause.
A crooked smile returned.
"But I like the concept," he continued lightly. "Fuel is still fuel… just a different method."
He glanced at Kuro.
"…And if it can be measured, it can be used."
Before the conversation could continue, footsteps echoed from the staircase.
A moment later, Pepper Potts appeared, descending into the workshop. In her hands were several additional pizza boxes—just delivered.
She stopped on the last step.
Her gaze immediately landed on the scene in front of her—stacked holograms.
The golden cube.
And two people clearly engaged in something far from an ordinary conversation.
"…I was gone for a moment," she said flatly, "and now this is… what? An upgrade…?"
She raised an eyebrow, then slightly lifted the pizza boxes in her hands.
"And yes—extra pizza has arrived. If you haven't blown anything up yet, that's good news."
Tony glanced at Pepper briefly, then back at Kuro—as if weighing how much explanation was actually necessary.
"…Upgrade," Tony Stark said casually. "With a bit of improvisation that's not in the manual."
His tone was light, but clearly—he was simplifying things on purpose.
Pepper narrowed her eyes, not entirely convinced, but also long accustomed to Tony's chaos enough not to immediately question it further.
"As long as your 'improvisation' doesn't end in an explosion," she replied flatly, "I'll consider that progress."
She walked closer, placing the pizza boxes on the workbench—slightly shifting components and tools without truly disturbing anything important.
Her gaze lingered on the golden cube.
A few seconds.
Assessing.
Strange, but not familiar.
"…I'm not going to ask," she finally muttered, mostly to herself.
Then she refocused on the two people in front of her.
"Alright. You've got food, drinks, and—" she glanced briefly at the stacked holograms, "—whatever this is."
Her tone turned slightly firmer.
"I only ask one thing."
A brief pause.
"Don't break anything."
She turned toward Tony.
"…again."
Tony raised both hands in partial surrender.
"Hey, the last time wasn't entirely my fault."
Pepper just stared at him flatly.
A moment of silence.
Then Tony sighed.
"…Okay, most of it was my fault."
Pepper nodded slightly, satisfied, then turned back toward the stairs.
But before going up—she stopped.
She glanced back at Kuro.
"And you," she said, her tone lighter again, "thank you for… the food and the visit."
A faint smile appeared.
Not formal.
More sincere.
Then she continued upstairs, leaving the two of them alone in the workshop.
Silence settled again.
Tony looked toward the staircase for a few seconds, making sure Pepper was truly gone.
Then—he turned back to Kuro.
His smile returned.
"…Alright," he said quietly.
His tone dropped.
More serious.
"…continue."
***
Some time had passed.
The night slowly swallowed the skies of the United States.
City lights flickered like artificial stars, but all of it… meant almost nothing to Kuro.
Completely absorbed in the Mark II design process with Tony Stark, he didn't even realize how much time had slipped away.
Daily check-in—missed.
At this moment, Kuro stood inside the Gate of Babylon.
A vast space without limits, more like an absolute vault than a typical Reality Marble.
It did not overlay the outside world, nor manifest a mental landscape—it existed purely as storage. Detached. Stable.
As far as the eye could see, a flawless white marble floor stretched endlessly.
Towering pillars rose upward, supporting an emptiness that felt both majestic and silent.
Across the floor, treasures were scattered—from ordinary objects to gold, jewels, ancient artifacts—even prototype Noble Phantasms.
All of them arranged… but not entirely neatly. As if this place was never meant to be displayed.
Only stored.
In front of him, a holographic system window appeared.
Ding!
[System detects that you have not performed your Check-in today.]
[Would you like to Check-in now?]
[Yes / No]
Without hesitation, Kuro raised his hand and selected Yes.
Ding!
[Congratulations, you have received Five Gacha Tickets.]
Five golden tickets materialized in the air out of nowhere.
Floating.
Glowing faintly.
Kuro immediately caught them one by one.
Silence.
His brows slightly furrowed.
"Tickets… again?" he muttered softly.
He stared at them for a moment, his expression not entirely satisfied.
"Since this isn't a seven-day bonus anymore…" he continued flatly, "…I'm not too confident this will give anything good."
He spun one of the tickets between his fingers.
Let out a light sigh.
"Well…"
His tone was casual—half resigned.
"…let's see."
A faint smile appeared.
"Hopefully… it's not a bust."