Almost the instant the word "Fire" left Musashi's mouth, he launched his attack.
"Wh-!"
Roterberg's eyes widened in surprise.
He was accustomed to facing opponents much faster than himself and usually managed to react to their attacks regardless.
One exception to that rule was his party member Enea. Even when Enea wasn't fighting seriously, it was practically impossible for Roterberg to follow his movements. And if he had to make a prediction, he imagined it would be much the same against the strongest knight of this kingdom.
But considering how this match had unfolded so far, he certainly hadn't expected even this opponent to unleash a movement so fast that he could barely perceive it.
Before the dwarf even realized what had happened, the exiled Hero was already standing directly in front of him, swinging his longer katana once again.
The relaxed expression Musashi had worn throughout most of the battle had completely vanished.
Now, every part of his body radiated nothing but absolute concentration to defeat his opponent.
His eyes remained fixed on Roterberg.
There wasn't a single unnecessary movement in any of his actions.
Nor would another word leave his mouth—aside from those required to activate his techniques—until either his opponent had been defeated or himself were to be defeated..
Just before the samurai's katana struck the armor protecting Roterberg's right shoulder, the blade became enveloped in faint flames.
The dwarf had cast no spell.
He immediately realized that the fire had to be one of the effects of Musashi's new technique.
"Co—"
Roterberg barely managed to utter the start of his spell.
But, of course, given the overwhelming difference in speed between himself and his opponent, he didn't even attempt to block the strike.
Even though it pained him to do so, he immediately released his odachi, allowing it to fall to the ground.
Instead, he placed his complete trust in the finest and most reliable armor he had ever forged.
At first, that gamble appeared to pay off.
The force behind Musashi's strikes was clearly greater than it had been while using Niten Ichi Ryu: Ring of Earth.
Even so, although the impacts hurt more than before, the armor itself seemed to be holding firm.
Furthermore, the flames coating the blades were so weak that Roterberg couldn't even feel their heat.
But then another two thousand strikes rained down.
After the first five hundred, the Hero began using his second katana as well, its blade likewise wrapped in those faint flames.
All of this happened before the blacksmith had even finished speaking.
In less than a second, after roughly the thousandth strike from the longer katana, Roterberg finally began to sense a trace of heat coming from the flames.
It was still almost imperceptible.
But it was undeniably there.
Only then did the dwarf finish pronouncing the spell.
"...me!"
The same massive shield as before instantly materialized in his hands.
It was one of the finest shields Roterberg had ever forged.
Its name was Sigfried, named after the Hero whom Roterberg had once witnessed saving his hometown from the devastating roar of a mighty dragon through the power of his invincible body.
The shield was a massive rectangle of shimmering metallic gray, with the image of a golden leaf engraved proudly at its center.
In terms of sheer durability, Sigfried surpassed even the blacksmith's treasured armor.
Musashi neither stopped his assault nor attempted to bypass the shield.
Instead, he simply shifted the target of his attacks from Roterberg's armor to the enormous shield standing in his way.
The relentless barrage continued.
After another twenty thousand strikes, the flames coating both katana blades had changed from a pale blue to a brilliant azure.
It was obvious that the temperature of the flames was steadily increasing.
Because Roterberg's armor was enchanted with powerful resistance against both fire and heat, as long as it remained intact, the heat could not reach the skin beneath it.
That also meant, however, that Roterberg was having trouble gauging how much the temperature of those flames was rising.
Recognizing the shield's remarkable resilience, Musashi pushed his speed to its absolute limit.
And so, after a single second had passed, the total number of strikes he had delivered reached three hundred million.
With the very next slash, the temperature of the flames surrounding both katanas rose to nearly the same level as the 'Energy of Nature' spell Katerina had unleashed during her battle against Caesar—
The temperature of the sun's photosphere itself.
Unable to withstand such unimaginable heat any longer, Sigfried, which had already begun to show signs of melting, was sliced diagonally in half by Musashi's next strike.
The severed portion melted away completely.
At that moment, Musashi looked Roterberg straight in the eyes.
Considering how many of his strikes the shield had managed to withstand, he realized it must have been one of the dwarf's finest creations—perhaps even one to which he felt a deep personal attachment.
That was why Musashi expected to see pain reflected in Roterberg's eyes.
And he was right about one thing.
That shield truly was precious to the dwarf. It had been one of the very first masterpieces he had forged after officially becoming a blacksmith. More importantly, it had been created as a tribute to the person to whom he owed his life. That was precisely why he had never sold it. Instead, he had forged a duplicate called Sigurd, which had long since found its way into someone else's hands.
But what Musashi saw nearly caused him to lose his concentration.
There was no grief.
No anger.
Only pure, unrestrained joy.
That single expression was enough to convince the samurai that the man standing before him was the greatest blacksmith he had ever encountered—not only in this life, but in his previous one as well.
And he was certain that no one would ever surpass him.
Because those eyes conveyed only one message:
"Thank you, my son. I can't wait to forge you again and make you stronger than ever before. This is going to be so much fun!"
Meanwhile, all that poured from the legendary blacksmith's mouth was booming laughter overflowing with optimism.
And because of the even greater respect that now filled his heart for his opponent, Musashi's determination to defeat him reached its absolute peak.
Without a moment's hesitation, the samurai resumed his relentless barrage of attacks.
The flames surrounding his blades continued to grow hotter and hotter.
Over the next half second alone, another one hundred and fifty million katana strikes crashed against Roterberg's armor.
By the final two strikes of that sequence, the temperature of the flames had risen to seven million degrees Celsius—the same temperature found in the hottest regions of the Sun's radiative zone.
Even Roterberg's armor possessed extraordinary resistance to heat.
It was so resilient that someone could have thrown it into the mouth of an active volcano, retrieved it a century later, and found it completely unharmed.
Yet even it had begun to glow a brilliant red in the areas repeatedly struck by the Hero's blazing swords, like iron fresh from the forge.
At this rate, only a few more strikes would finally be enough to breach it.
Every technique that composed Miyamoto Musashi's History Magic, The Book of Five Rings, possessed effects that enhanced both Musashi himself and the swords he wielded.
In the case of Niten Ichi Ryu: Ring of Fire, the enhancements granted directly to Musashi were a tremendous increase in both his speed and physical strength.
Useful though those boosts certainly were, they were by no means the technique's greatest asset.
After all, exceptional physical strength and speed could still be attained through relentless training and extraordinary talent with the Physical Enhancement spell.
The true power of Ring of Fire lay in the effect it bestowed upon Musashi's blades.
Each katana became enveloped in flames that initially burned no hotter than the flame of an ordinary candle.
However, every single time one of those blades struck a solid object, the temperature of the flames increased.
Within an astonishingly short period—as had just happened—their heat could climb to temperatures rivaling those found within the Sun itself.
Theoretically, if Musashi landed enough consecutive strikes, those flames could even reach Planck temperature—the highest temperature theoretically possible in the universe.
In reality, however, his mana or physical stamina would be completely exhausted long before the flames could ever approach such an unimaginable level.
No matter how hot the flames became, however, they never harmed Musashi himself.
Nor did they affect the clothing he wore, the gases in the surrounding air, or anything that was not in direct contact with the flames.
Even so, at the temperature his blades had already reached, anything lacking truly extraordinary heat resistance would be reduced to ashes the instant it touched those flames.
And that was exactly what would happen if even a small portion of the dwarf's exposed skin came into contact with them for the briefest moment.
Had Musashi been fighting an ordinary opponent, then after reaching this level of concentration, he would simply have sliced open the armor, followed immediately with another strike through the opening, and incinerated his opponent where he stood.
'But I could never call myself a swordsman again if I chose to eliminate a blacksmith like this from the world,' Musashi thought.
For that reason, he had already decided that the instant his flaming katanas finally breached Roterberg's armor, he would immediately switch to a different technique.
But before the strike that would have shattered the legendary blacksmith's armor could land, something so unexpected happened that it completely halted Musashi's assault for the remainder of that half second.
Suddenly, every weapon attached to Roterberg's back fell to the ground.
Until that moment, they had remained secured there thanks to a General Magic spell called Attach.
The dwarf had deliberately deactivated it.
Then he cast:
"Come!"
A naginata nearly two meters long instantly appeared in his hands.
Its blade was as yellow as an eagle's beak, with emerald-green crystals protruding from it at irregular intervals.
At the opposite end of the shaft, three emerald-colored feathers were attached to a sturdy metal ring.
Taking advantage of the split second Musashi had inadvertently granted him, Roterberg poured an enormous amount of mana into the naginata, which was already aimed directly at his opponent.
The green crystals flashed brilliantly for an instant.
Then, almost immediately, a powerful projectile of compressed wind burst forth from the weapon.
Because the flames surrounding Musashi's swords could not affect something as intangible as air itself, he had no way of blocking the attack.
The projectile struck him squarely.
The impact hurled the Hero several meters backward.
Still maintaining his absolute concentration, however, the exiled swordsman immediately regained his footing and launched himself forward once more. He had no intention of wasting the opportunity he had created.
At that point, an attack from virtually any of his techniques would have been enough to shatter the armor, given the condition in which he had left it.
But the moment he attempted to move within a meter of his opponent, an overwhelmingly powerful wall of wind blocked his path.
Musashi was forced to stop.
Only then did he carefully examine his opponent.
To his astonishment, Roterberg had seemingly disappeared.
In his place stood a massive cylindrical tornado.
Yet not even the deafening roar of the violent winds composing that whirlwind could drown out the booming laughter echoing from within it.
"AHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAAHAHAH!"
"These techniques of yours, which are so clearly part of your History Magic—it's obvious that someone who isn't particularly gifted in magic couldn't possibly wield three spells of such incredible power while controlling different attributes—are absolutely fascinating!"
"Thank you, Hero Musashi!"
"You've given me wonderful inspiration for some truly interesting new weapons. I can hardly wait to return to my workshop and begin forging them!"
"But first…"
His joyful voice grew even louder.
"...since it's obvious that even my armor has its limits…"
That powerful voice, naturally, belonged to Roterberg.
Through the swirling gusts that shielded him, Musashi could barely make out the dwarf's silhouette.
Even though visibility was poor, he could still distinguish one important detail.
He was rapidly spinning the naginata he had just used to fend him off above his head. Without a doubt, it was the source of the violent tornado surrounding him.
'I can't get any closer...' Musashi thought.
'But as long as I remain at this distance, there doesn't seem to be any immediate danger. And judging bythe tremendous amount of mana I can sense within that tornado, maintaining this weapon must consume an enormous amount of mana. There's a chance that if I simply wait here without doing anything, Roterberg will eventually exhaust his mana reserves, causing the tornado to dissipate on its own... although I doubt it will be that sim-.'
The samurai's train of thought was abruptly interrupted.
The dwarf's excited voice rang out once more, louder than ever.
"Prove to me that you can overcome even this... my final test!"
At that very moment, many of the weapons Roterberg had scattered across the ground were swept up into the tornado.
As they spun within its powerful currents, they accelerated to astonishing speeds.
Then, without warning, one of them—a spear over two and a half meters long—shot out of the whirlwind and hurtled straight toward Musashi.
The force and speed behind that single projectile were at least ten times greater than those of the spear Roterberg had thrown at the very beginning of the match.
But the samurai remained focused.