With the final Shadow Rider defeated, the Keyholders could finally relax a little.
Dr. Crowler was practically glowing with pride this time. After all, the card Hikaru Amagi drew to pull off his turnaround had been Fusion Substitute, one of the "trash fusions" he'd once scoffed at—except this one was one he had purchased. For the first time, he felt like he'd actually contributed. A real sense of shared victory.
Still, one thing rubbed him the wrong way: in the end, that normally timid Professor Lyman Banner had told him to look after the students.
How insulting!
Most of the Slifer Red students were still in a slump, Jaden Yuki especially. Days passed and he barely made a sound—a rare quiet settling over the usually hyperactive duelist.
It was his first real loss—his first true farewell. Someone familiar, kind, turning to nothing before his eyes… It shook him to the core.
But this was also a vital moment of growth—perhaps the most important of his life. Even Winged Kuriboh couldn't fully lift his spirits these past few days. Only his bonded HERO spirits offered some weak comfort.
The only one seemingly unaffected was Atticus Rhodes, who, despite being KO'd in a Shadow Duel by Banner, went around strumming his guitar cheerfully, bragging that he'd faced a real pro. He even joked Zane didn't need to worry anymore—he was healthy enough to wield Red-Eyes Black Dragon with or without the mask.
That was a key difference from what Hikaru remembered from the original timeline.
In the original story, using Red-Eyes again meant putting the mask back on and enduring the pain that came with borrowing Darkness's power. But here, things had changed. Darkness's avatar had completely left the mask, and Atticus could summon Red-Eyes freely.
Three rare cards for free? Atticus was actually kind of grateful to Banner… if only he hadn't been blasted so hard mid-duel.
Hikaru, meanwhile, returned to his usual rhythm in the Fusion Club. And when he wasn't dueling or mentoring, he poured over the book Banner had left him—The Emerald Codex.
Technically, this book could've been called Banner's Codex. It wasn't the Emerald Tablet of legend that symbolized the universal truths of alchemy—it was a custom text Banner had composed himself, compiling all his knowledge, experiments, and dimensional research. The name was just a holdover. He'd never bothered changing it.
Inside were pages upon pages of handwritten alchemical records, spell theories, even blueprints for constructing a Dimensional Gate. There were also a shocking number of dimensional coordinates listed, dizzying in scope.
If Hikaru could solve the riddles within the book, he'd unlock access to those coordinates. And if he truly mastered the construction of Dimensional Gates, he wouldn't even need the Academy's portals anymore.
Among the pages was the key to that artificial dimension Banner had pulled them into—the one with the massive forge and strange sky. Hikaru could now access it freely via the book.
This was a monumental gift.
Forget everything else—just the forge alone, the real "goods" left behind by Banner, were an invaluable treasure trove.
No matter how much Hikaru upgraded the tools he bought, they could never match what Banner had left him. Just the giant furnace—big enough to fill half a classroom—was something no student could ever hope to install on campus.
"You really hit the jackpot, huh?"
Tierra appeared in the forge, spinning lazily in the air, eyes flicking across the room. Then her gaze locked onto Hikaru's Deck. "I looked into it before. This dimension… it's artificial, right? Your teacher must've crafted it himself, built into your school's subspace. Every time the school uses a dimensional gate, he could hijack it from the backdoor and drag people here."
"…You don't need to explain stuff that's already happened."
"I'm saying," she grinned, "your Duel Spirits could live here—when you're not dueling, they don't have to sit trapped in cards. This space is stable. They could move freely."
With a snap of her fingers, she called out: "Alright, everyone—out you go!"
The first to pop out in a panic was White Quartz Captain, followed by Golden Idol Priest, Cyclopean Champion, and the Molten Alchemist. The Flame Sword Brothers emerged only after Hikaru nodded in approval.
The space was massive, yet the arrival of all these spirits still made it feel a little crowded.
Truthfully, seeing them all together sparked something in Hikaru. A sense of pride. These were his comrades.
"This could really work…" he muttered. "Normally, you guys can only act when summoned. But here, you can roam freely. It's better for everyone."
Each one of these spirits shared his passion for fusion. Giving them a place to breathe—literally—seemed right.
"This artificial dimension's huge," Tierra added. "Those floating 'planets' in the sky aren't real-scale, but they're big enough to live on. Oh, and you—yeah, the Alchemist—stop staring at the gear panel like that. If you want to tinker, ask your holder."
"Ah—!" Molten Alchemist snapped out of his trance and looked to Hikaru with sparkling eyes.
Now Hikaru understood Tierra's meaning.
If Molten Alchemist could perform syntheses here—even just low-level Normal Monsters—that would be huge. More card sources, more versatility. Not to mention, prepping more advanced stuff.
Hikaru gave him a nod.
"All done with the small talk. C'mon, human—let's find it!"
"Find… what?"
"The core! Or… maybe a card?" Tierra spun her staff in the air, head tilted. "Whatever it is, it's calling. Let's go!"
She darted off with giddy energy. Hikaru sighed, but gave chase. Letting a godlike being like Tierra run wild here? That was a no-go. Plus, this was Banner's forge. If she broke something…
After a while, Tierra stopped before what looked like a control panel. She pointed, trembling with excitement.
"Here! It's here!"
Her fingers shook. Hikaru had never seen her this animated. Not even when she took over Winda's body had she looked so thrilled.
Hikaru opened the casing. His eyes widened.
Inside was a card.
A green Spell Card.
Philosopher's Stone – Sabbaciel
Just reading the effect made his breath catch.
Pay half your Life Points. This card lets you swap a card in your possession (including those not in your Deck) into your hand. Can be used a maximum of three times across all Duels.
Pure power.
Absolute power.
"This…" Hikaru stared, jaw slack.
"I knew it!" Tierra punched her fist into her palm. "I told you! No human, no matter how genius, could create an artificial dimension alone!"
"How about it, human?" Tierra's voice was dripping with temptation. "Do you want to touch that power?"
Hikaru swallowed.
He reached out—but stopped, inches away. He steadied his breathing. Lips dry, he asked:
"…There's something more, right?"
Tierra's grin widened.
"You're fun, Hikaru Amagi."
She floated closer, eyes gleaming.
"Let's go deeper. There's more to this dimension than you ever imagined."