"What a wonder... what exactly is going on here?"
Inside a certain laboratory, a man in a white coat, a strange wing-shaped emblem pinned to his chest, stood before a massive machine, curiosity gleaming in his eyes.
Before him, a Y-Dragon Head lay lifeless atop a platform, its metallic body twitching occasionally with crackling static.
"What's the principle here?" he murmured, stroking his chin.
"Mechanical... yet spiritual. How is that even possible?"
His real name wasn't important — they simply called him the Allied Doctor.
In this world, with interdimensional travel now a reality, many once-obscure scientists and outcasts had found new opportunities.
But even among these, there were still those too "special" to be recognized even by KaibaCorp — researchers who conducted forbidden "Spirit Experiments."
Driven by curiosity about the soul, a lust for immortality, or simply mad obsession, they were shunned, unwelcome even among fringe scientists.
The Allied Doctor was one of them.
But then, someone had approached him.
Someone offering him funds, resources, and power — on the condition that he worked in hidden dimensions, beyond KaibaCorp's jurisdiction, crafting "spirit soldiers that would never betray."
Simple enough, right?
What was the big deal?
They were just machines, after all.
BOOM—
As the Doctor was scanning the data, the entire building shook violently. He stumbled, grabbing onto the machine for balance.
"What the hell now!? Those damn robots attacking again?"
He glanced toward the entrance, barking impatiently.
"We just rounded up a batch last time — haven't they learned yet?"
As he spoke, a soldier wearing a purple uniform sprinted into the lab, saluted sharply, and said:
"Doctor, no major issue — just an intruder."
"An intruder?" The Doctor raised an eyebrow. "A human?"
"Yes, sir — just some Yellow Dorm kid from Duel Academy. Nothing to worry about."
The soldier thumped his chest confidently.
"We're top graduates from Slifer Red — a single Yellow's no match for us."
The Doctor, not versed in Duel Academy's hierarchies, accepted the explanation without much thought.
Still...
How did an active student reach this dimension?
This dimension... wasn't it exclusively explored by Professor Akaba?
He frowned but turned back to his work. His experiments were far more important.
The mechanical spirits — though outwardly robotic — dismantled like nothing he'd ever seen.
They resisted modification. They disintegrated into stardust when broken.
No circuits. No wiring.
Were these really machines?
Or something else, wearing the shape of machines?
BOOOOM!!!
Another blast — this one even worse — rocked the entire lab, nearly knocking the Doctor off his feet.
"What the—!?"
Before he could stabilize himself, another soldier bolted into the lab.
"What now!?"
"The intruder! He's insanely strong — how can a Yellow student be this powerful!?"
"Doctor, hang on — we're gathering more troops! There's no way he can overturn everything alone!"
The Doctor just stood there, stunned.
"Maybe... maybe you should call the Commander?" he muttered.
"No way! It's just a Yellow student—!"
Even as the soldier's words echoed, he was already sprinting away.
Moments later, a flood of soldiers and spirit machines surged past the lab.
What... the hell is happening?
The Doctor turned toward the other side of the lab — where the resting quarters were — and saw a man stumbling into view.
Pale-faced, drenched in cold sweat, his right arm shriveled and twisted grotesquely — a man barely clinging to life.
Commander Morishima.
"Commander," the Doctor greeted nervously.
"Sounds like we have an intruder."
"An intruder?" Morishima rasped.
"Spirit soldiers?"
"No... they said it's a Yellow Dorm student."
"...Yellow Dorm...?"
Morishima's eyes sharpened — a flicker of recognition sparking — and then he muttered:
"No way...!"
More explosions echoed, rattling the walls.
The Commander snapped upright.
"Doctor, come with me!"
"R-Right—"
But before they could leave, a shriek pierced the lab:
"Direct attack—AHHHHHH!!"
A soldier in purple uniform, mask cracked, was hurled through the hallway like a ragdoll, bouncing along the ground, groaning in pain.
A voice echoed after him:
"Is that all you've got, senior?"
RATATATATA—
Gunfire erupted in the corridors. Soldiers had given up on dueling — they opened fire with live ammunition.
But then:
CLANG! CLANG! CLANG!
The gunshots stopped — replaced by screaming.
Cold sweat drenched the Doctor's back.
Something was terribly wrong.
Step. Step.
Slow, deliberate footsteps echoed toward the lab — calm, unhurried.
The Doctor and Morishima stared at the door, frozen stiff.
Each step cranked up the tension until the Doctor was wiping his forehead again and again, while Morishima's lips trembled.
Finally, he rasped:
"Hikaru Amagi..."
As the name fell from his lips, the figure entered.
Hikaru Amagi — walking casually through the chaos — appeared at the threshold.
The Doctor screamed internally and collapsed backward.
Morishima gulped hard.
"You know me?" Hikaru said lazily, glancing over the devastated lab, frowning as he took in the dismantled mechanical spirits strewn about.
He had considered sneaking in quietly — but seeing how these fools had butchered the spirits, any thought of mercy vanished.
"Hmph... ordinary soldiers aren't even allowed to return to the human world or watch the news," Morishima muttered bitterly. "But your bounty's different."
"Meh. Let 'em put a bounty on my head." Hikaru shrugged. "Won't be the first."
"You... you dare come looking for us?" Morishima spat, spreading his left hand.
With a sharp click, a Duel Disk deployed from his arm.
"Don't think I'm like those weaklings! At Duel Academy, my Spirit Compatibility already reached the Seven Stars level — far beyond you!"
Seven Stars — Zane Truesdale's current standard.
But so what?
Spirit Compatibility meant nothing against true strength.
"You think... you can do this and just walk away?" Morishima roared.
He clenched his teeth, sparks crackling from his body.
"I'll crush you — and collect the bounty the Professor placed on your head!"
"I'll show you the terrifying power the Professor gifted me!"
Hikaru idly shuffled his deck, then said flatly:
"The Sacred Beasts, huh?"
"What—!?"
Morishima froze, stunned.
Hikaru just chuckled darkly.
A wild, almost feral grin spread across his face as he snapped his Duel Disk open.
"Then let me show you the full might of my Fusion Deck!"
A burst of violet light exploded from Hikaru's body, a howling shockwave scattering debris and scrap all around him.
SLAM!
Morishima instinctively stumbled back a step.
Before him, Hikaru Amagi no longer looked human.
Purple light pulsed around him like liquid darkness. Dozens of puppet strings danced wildly, whipping through the air like demonic wings.
In that instant, Hikaru looked less like a Duelist — and more like a devil unleashed from the pit.
Wait, wait, wait — I'm supposed to be the bad guy here, right!?
Morishima's mind screamed as he swallowed hard.
No — it's fine. I still have this!
He clutched the card — the one weapon Professor Akaba had given him.
Hammon, Lord of Striking Thunder.
Even against an army, Hammon could hold the line.
With a Sacred Beast in hand, no punk Yellow student could defeat him!
DUEL!
Commander Morishima — LP: 4000
Hikaru Amagi — LP: 4000