Seven years ago, within the Higher-Dimensional Space—
After being sublimated by the energy of the Cubic Realm, Kaiba encountered that man within a pure white void of the higher dimension.
"The third reincarnation? You've actually gone through this… three whole times?"
Even as instinct urged him to doubt the words of the man who called himself King Solomon, it was as though a keyword had been triggered—an overwhelming sense of déjà vu surged through Kaiba's mind.
"Solomon… was all of this arranged by you?"
"No, Kaiba. All three reincarnations were born of your own will. You personally chose the long journey. I merely lent a small helping hand."
Respect was clearly visible in Dr. Romani's eyes as he spoke solemnly.
"In order to change this world's destined destruction—
In order to change Chiyuki's fate—
I entrusted my remaining power to you and constructed the System of Duelist No. 002."
"So something like this was actually possible…!"
Even though Kaiba was a staunch atheist and a firm believer in scientific supremacy, memory did not lie. The moment he met Solomon, all memories of the three reincarnations returned in full.
Though his shock had yet to fully subside, Kaiba accepted the truth almost immediately. More accurately, he no longer wished to dwell on the past.
"So what's the result? After making me reincarnate three times—did anything change?"
At this point, the process of reincarnation itself mattered far less than the outcome.
"Did I save her?"
Placing a hand on Kaiba's shoulder, Dr. Romani smiled gently.
"Congratulations. You succeeded, Kaiba Seto. Though each reincarnation brought only minor changes, the accumulated overlap of possibilities finally crossed the threshold—from quantitative change to qualitative transformation—within Chiyuki."
Within the higher-dimensional space, Kaiba and Dr. Romani could clearly observe everything happening on the battlefield below.
"And the final move that decided victory relied precisely on the miracle born from those layered possibilities—the one and only path to triumph.
Now, in the name of Solomon—
'Liberation at the End of Reincarnation, Binding the World Thereafter!'"
"My turn—draw!
Then, I perform a Summon—Heroic Spirit: Arthur Pendragon!!"
[Heroic Spirit – Arthur Pendragon ★★★★★★★★ (Level 8)][LIGHT][Warrior/Effect][ATK 2400/DEF 2000]
The radiant holy sword of starlight—
A golden blade forged to repel nearly all evil, created to defeat invaders seeking the destruction of the stars themselves.
As Arthur drew the sacred sword, the dimensional cubes and the darkness of the Cubic Evil God were swept from the field.
"Release of the Thirteen Seals!—When thirteen or more 'Heroic Spirit' monsters exist in the Graveyard or banished zone, the final effect of Heroic Spirit – Arthur Pendragon activates!"
Arthur:
"This… is a battle to save the world!!"
"So strong…"
Witnessing Arthur condense its light and annihilate the Dark Cubic in a single strike, Kaiba couldn't help but speak from the heart.
"So this is the power Hoshino wields now…"
"Right? Right? Amazing, isn't she~"
Dr. Romani grinned proudly, like a parent boasting about their own child.
"Chiyuki has talent in everything she does. Her strength isn't simply the result of borrowing power from Heroic Spirits."
The tension finally easing from his chest, Kaiba nodded.
"Then it's truly over now. In the Dimensional Field Duel, the Dark Cubic has already been defeated."
"No. This is only the beginning, Kaiba Seto."
Dr. Romani's previously relaxed expression hardened.
"As I said earlier—this is an extremely rare worldline, one forged only after three attempts, the sole path that leads to a miracle of victory."
Kaiba frowned slightly.
"Speak plainly."
Dr. Romani explained:
"Although this worldline leads to victory, when facing the true Age of Destruction that lies a hundred years in the future… relying solely on Chiyuki's power gives you very little chance of success."
"A hundred years later?! Humans couldn't possibly survive that long—even Hoshino—"
Kaiba cut himself off mid-sentence.
If it were Hoshino… it might actually be possible.
The bloodline of Atlantis had allowed monsters like Dartz to live for tens of thousands of years. Someone of the same lineage might well endure a century.
Dr. Romani continued:
"And that is precisely the truth. Chiyuki has already lost once."
In the original worldline, the defeated Chiyuki transferred her power through a space-time tunnel to this world's Chiyuki—who was battling Paradox—and then met her final end.
"The Age of Destruction is closer to this planet's destined fate. Reversing it will be no easier than repairing Human Order itself."
"I told you to speak plainly. What do I need to do?"
Dr. Romani's eyebrows twitched slightly. He hadn't expected Kaiba to show even a moment's hesitation—yet there was none.
Having regained the memories of three reincarnations, Kaiba now possessed a resolve surpassing anyone else in the world.
"In the first two reincarnations, Kaiba—you stopped here. After all, you were still human, unable to reach the battlefield of the distant future. This time, I want you to become a Guardian of the World's Counter Force."
"Guardian of the Counter Force?"
Hearing the term for the first time, Kaiba frowned even more deeply.
"It's not exactly the same, but in this world, it would be something akin to the legendary Three Knights you've encountered before. In other words—a High Duel Spirit."
Kaiba stared in disbelief.
"A High Duel Spirit… you want me to become something like that?"
"If you become a Guardian of the Counter Force, you'll be able to reach that distant battlefield.
But in exchange, you must abandon everything you possess as a human—wealth, friends, family.
It will be a journey far lonelier than even three reincarnations."
Dr. Romani's vision blurred slightly. With what little power he had left, he knew this was likely his final chance.
Even so, he asked carefully:
"Make your choice, Kaiba… Of course, I won't force you."
Even with Kaiba's extraordinary resolve, Dr. Romani understood this was not a decision that could be coerced. The battlefield lay a hundred years in the future—far beyond the reach of ordinary humans.
Even if Kaiba chose to do nothing, he could still live out the rest of his life in peace, untouched by that distant catastrophe.
It's like someone suddenly telling you that the Earth will explode 500 years from now—but if you sacrifice yourself, you can prevent it. I believe that 90% of people would never choose to make that sacrifice.
And the choice Kaiba now faced was precisely that:
To wager everything around him on an unknown possibility.
"What about Mokuba? If I'm gone… what happens to Mokuba?"
"In order to minimize interference with the progression of the worldline, after you become a Guardian of the Counter Force, I will create an existence equivalent to Kaiba Seto. Memories, personality—even your intellect—will be identical, so your younger brother won't notice anything amiss."
After all, if the president of KaibaCorp were to suddenly disappear from history without warning, the excessive deviation in the worldline could generate even greater threats. This was something Dr. Romani had already taken into consideration.
"Although the duplicate will be no different from you, it will be unable to wield any power. Interpreted under this world's rules, it simply means it will be unable to duel."
"So it just can't duel?"
Kaiba narrowed his eyes. "Solomon… just who are you, really, to be capable of something like this?"
To foresee the future, initiate reincarnation, and casually replicate his very existence—Kaiba couldn't comprehend what kind of terrifying being this gentle, spring-breeze-smiling man truly was.
"I'm just an ordinary Chaldea staff member~"
Dr. Romani smiled. "So—what's your decision?"
"Since you've already gone this far, I don't really have a reason to refuse, do I? As long as 'Kaiba Seto' continues to exist—even if he can't duel—then as long as it's me, I can still protect Mokuba."
"I'll confirm one last time," Dr. Romani said seriously.
"From today onward, Kaiba Seto will continue to exist—but the duelist known as Kaiba Seto will vanish from history forever. Is that acceptable?"
"Enough talk. Before I start regretting this, do what you need to do."
.
..
...
"As expected, this outfit really does suit you better if you're going to be a Guardian of the Counter Force."
Examining the Blue-Eyes White Dragon mask in his hands, Dr. Romani nodded in satisfaction.
"If you were a girl, I'd definitely have prepared a magical-girl outfit for you—but unfortunately, you're a guy. That said, no man could possibly refuse becoming a masked hero, right?"
Kaiba's mouth twitched slightly. To be honest, he was already starting to regret this.
"What, not satisfied? I specifically designed the mask based on your tastes—it's modeled after Blue-Eyes White Dragon, you know."
What made it even more frustrating was that the mask… was infuriatingly cool.
"So just by wearing this, I become a Guardian of the World's Counter Force?"
Handing the mask to Kaiba, Dr. Romani explained:
"Putting on the mask is only the beginning. With your current power, even if you become a Guardian, you won't be able to protect anything yet."
Kaiba didn't deny it—after all, he had just lost to Hoshino in that duel.
"After becoming a Guardian of the Counter Force, you'll gain the ability to travel worldlines. What you must do now is reincarnate across countless timelines, constantly fighting and sharpening your strength."
Dr. Romani gave his final warning:
"Kaiba, what awaits you ahead is nothing but endless battle. If you turn back now, it's still not too late. I can say this without exaggeration—if you continue forward, you will unquestionably be walking straight into hell."
"Stop spouting useless nonsense."
Kaiba's eyes burned with resolve.
"I, Kaiba Seto, never turn back. I only look toward the future!"
"Well said. But from this moment on… you are no longer Kaiba Seto."
As he transferred his remaining power into Kaiba, Dr. Romani declared:
"From now on, the duelist who commands Blue-Eyes White Dragon in this world will no longer be Kaiba Seto—but you—Kaiba Man!"
"Finally, in the name of King Solomon, I offer you my heartfelt gratitude for the sacrifice you've made to protect this world… Kaiba Man."
Putting on the mask personally handed to him by Dr. Romani, Kaiba Man let the corner of his mouth curl upward.
"Hmph. Don't get it twisted, King Solomon. I have zero interest in protecting this world."
.
..
...
Battle!
"Prepare yourself, Pegasus! Destructive Burst Stream—direct attack!!"
"Oh, no!"
[Pegasus LP 3000 → 0]
More battle!
"Marik! Is the power of a god really so insignificant?!
Then feel the might of the Ultimate Dragon—power beyond even the gods!"
"H-How is this possible?!
The invincible Winged Dragon of Ra… defeated by a mere white dragon?!"
[Marik LP 1 → 0]
Endless battle!
"Dartz! A wandering soul that lingered for ten thousand years—have you finally found rest?
If not, then I'll send you back into the abyss!
Abyss-Eyes White Dragon—effect activation!!"
"Power surpassing Orichalcos' infinite darkness…?!
Why—why does such an existence even exist?!"
[Dartz LP 2000 → 0]
He could no longer count how many times he had fought.
Defeat.
Reincarnation.
Defeat.
Reincarnation.
Just as Dr. Romani had said, Kaiba Man felt his power steadily expand, step by step.
And after trampling over the remains of enemies who once threatened this world countless times over, Kaiba Man finally arrived at this point.
"I'm just saying—this old man Seto… he's no ordinary opponent!"
The pure white power that traversed time and reincarnation gathered in Kaiba Man's hand.
The card flicked from his fingertips was proof of supreme strength—earned through innumerable hellish battles.
"Pure white power dwelling at the source of infinite time—
Raise wings that tremble amid the resonance of entwined souls!
Emerge from the azure abyss—Blue-Eyes Abyss Dragon!!"
With effect damage from a total of four Dragon-type monsters, Hoshino's remaining Life Points were wiped out instantly.
[Hoshino Chiyuki LP 2000 → 0]
"Damn it! How the hell do you still have Blue-Eyes Abyss Dragon?!
And you top-decked it as your last card too—are you kidding me?!"
What should have been a complete reversal was instead forcefully ended by Kaiba Man's finishing blow—leaving Hoshino understandably furious.
["Reversing the duel even after three Blue-Eyes were banished… This guy is on a completely different level from Kaiba."]
"I told you already—at your current level, Hoshino, you're still far from being able to defeat me."
Having won countless battles across endless reincarnations, Kaiba Man thought he had grown numb to victory—
Yet in this duel, he felt its joy once more, for the first time in a long while.
"…Still, I'll give you credit where it's due," he added calmly.
"You fought well."