The afternoon drifted on with its deceptive calm, the sun now a bit lower, painting the sky in reddish hues that blended with orange.
The breeze whispered through the vines, and the lake reflected the twilight like an untouched mirror.
The birdsong had ceased, leaving only a heavy silence, as if the very air were holding its breath.
Kazuya stood motionless, his icy blue eyes fixed on Sirzechs and Grayfia. The provocative smile from before was gone, replaced by a hard, almost predatory expression. His white hair gleamed under the golden light, but there was no warmth in his face. Only a cold, sharp determination, honed like a blade.
The silence stretched, dense, suffocating, until he shattered the stillness with a sudden movement.
His right hand rose, making a simple gesture with two fingers in front of his face—one finger hooked like a claw, the other straight—and the air around him vibrated, warping as if something invisible and powerful were taking shape. A dense, almost tangible energy emanated from him, causing the ground beneath his feet to tremble faintly.
Without a word, Kazuya advanced.
His eyes gleamed with icy intensity, and with a swift gesture, he moved his hand into an activation "Mudra" for a Magecraft spell that created, in that moment...
From his body, a curtain of light, almost liquid, poured forth like spilled ink, spreading in waves that swallowed the scenery.
The mansion, the lake, the flowering vines—everything dissolved into a blur of colors, as if the world were a canvas being repainted. Sirzechs and Grayfia, caught in the center of the magic, felt the ground vanish beneath their feet, gravity distorting as the curtain pulled them to another place.
When the light stabilized, the world had changed.
To Sirzechs and Grayfia's eyes, Kazuya's estate was no more.
In its place, a mountain range rose, imposing and wild, with jagged peaks slicing through a gray, turbulent sky.
The wind howled through the canyons, carrying a biting cold that stung the skin. Dark, irregular rocks littered the terrain, and the ground beneath their feet was rough, unstable, as if it could give way at any moment.
"This is—" Sirzechs widened his eyes, scanning his surroundings with a look of disbelief.
He wasn't exactly an expert in Sacred Gears—that was an area he left to someone like Azazel. But even so, with centuries of life and experience, he had witnessed all kinds of supernatural powers. And yet… nothing like this. He had never heard of magic capable of creating an artificial dimension "instantaneously."
All factions that possessed their own "domains," like the Olympus of the Greeks or the Takamagahara of the Japanese, had established them eons ago. And there were no records of them using "conventional" magic for it. In most cases, those worlds were shaped by the hands of gods, using their own divine nature, or, as in the case of the Underworld, by the Original Four Maous, with no record of how they had done it.
Even Ajuka, with all his genius, had only managed to create an Artificial Sky in the Underworld, an imitation of the human world's sky, through magical technology and after years of study—and that was only possible with the assistance of the other two [Maous] and himself.
And even that was considered an extraordinary feat.
In other words, magic of this magnitude simply shouldn't be possible for an ordinary human.
He refused to believe the boy was some hidden creator deity, emerging from the shadows without leaving a trace. He had already investigated his background: just an ordinary human, orphaned early after losing his parents in a car accident, raised in an orphanage with no sign of involvement in the supernatural world. But even so, the fact that he had managed to create an artificial dimension…
The only logical conclusion was that it was his Sacred Gear. And among the thirteen known Longinus, there was only one with such capability, one he had heard of but never witnessed personally.
"This power…" he murmured, eyes narrowed, as if speaking to himself. "[Dimension Lost]?"
Grayfia narrowed her eyes and tensed, murmuring, "That explains the barriers around his estate that prevent anyone from entering. So, this is his Sacred Gear…? But didn't it have the characteristic of purple mist?"
She, of course, had heard of the Longinus [Dimension Lost], capable of creating a special mist that could block any attack and transport anything within it to an artificial space. It was the strongest Sacred Gear of the barrier and space type, but according to her knowledge, its characteristics manifested through a purple mist.
Hearing their words, Kazuya merely scoffed inwardly, saying, "You can think that way…"
Obviously, it had nothing to do with his Sacred Gear. It was a spell that only worked thanks to his personal abilities.
This spell mimicked the functionality of a Marble Phantasm, an ability belonging to Nature Spirits, entities that represent the "sense of touch" of the planet itself. This technique allows them to reshape the world around them through probabilistic manipulation. By connecting their will to that of the planet, they can mold the environment according to their imagination.
However, this ability does not apply to beings with independent existence from the world, such as humans or animals. In essence, it is a technique focused solely on transforming the scenery, altering the "background" of reality.
The concept behind it is rooted in probability theory, specifically in the so-called "clustering illusion." It's like a mathematical metaphor: imagine a bag filled with black marbles and just one white one, with a 1% chance of drawing it. Marble Phantasm is the ability to distort that reality and make the chance of picking the white marble jump to 100%, ensuring that outcome as if it were inevitable.
Using the same logic as Marble Phantasm, this spell seized a fragment of reality and shaped it according to his will, as if painting the world in his own image.
The new reality expanded indefinitely while completely isolating the space from the rest of the world. Although the "location" technically remained in front of the mansion, it now existed within an artificial dimension, separate from natural laws. Naturally, his servants could cross the barrier without resistance. Thanks to the refined control he exercised over the technique, he could determine, with almost instinctive precision, who was allowed to enter and who would be barred.
He named this spell [Tír-na-nÓg], inspired by one of the most famous legends of Celtic mythology, particularly tied to the Ossianic Cycle. Described as a mystical paradise, Tír-na-nÓg was a land where time did not flow, youth was eternal, and there were no diseases, wars, or death. It was also one of the many names attributed to the [Reverse Side of the World] from his past life, so he wanted to pay homage to it, but honestly, it was more because he couldn't think of a better name…
After hearing his words, Sirzechs confirmed his assumption that it was his Longinus. He sighed, "So, we have no choice but to fight, do we?"
"No… I already told you before, besides being dumb, are you deaf?" Kazuya mocked, removing his blazer—he didn't want to end up tearing it—then cracked his neck and assumed a stance.
Sirzechs frowned.
But before he could say or do anything, Grayfia stepped forward. Her [Demonic Power] surged around her body in waves of icy blue, dense enough to make the air feel heavy.
Then came the change in the environment.
A tremor ran through the ground, followed by sharp cracks, as if the very rock were yielding to the pressure. The mountain range shook with a dull echo that spread through the peaks, something between a muffled thunder and the groan of an ancient structure on the verge of collapse.
Without even turning, she said in a firm voice:
"Sirzechs-sama, let me handle this…"
As soon as she finished speaking, Grayfia advanced, her cold eyes fixed on the albino boy before her.
The air around her crackled with the rising pressure of her [Demonic Power].
She was a proud woman.
Always had been…
And that boy… he had insulted her husband more than once.
She simply couldn't ignore it anymore. She wanted to teach him a lesson—direct, clear, and definitive.
Sirzechs remained a step behind, his brow slightly furrowed, but he didn't interfere, at least for now. He let out a restrained sigh. He was worried. Creating an alternate dimension of that magnitude… he couldn't even sense precisely how vast that space was. That alone spoke volumes about the mastery the boy had achieved over his Longinus. He was strong, no doubt.
Still, his wife was more than capable of handling it. He had confidence in that…
On the other hand, Kazuya, with his flowing white hair, observed her with an expression devoid of any emotion, save for disdain.
"You first, then?" he said calmly, his voice as sharp as the wind whipping through the mountains. "Fine. Let's make this quick. I have an appointment later."
Despite what he said, he couldn't deny he was curious. He wanted to see what the strongest Queen of the Underworld, someone capable of rivaling the current four [Maous], was truly capable of. From what he recalled from the original story, it was said she was on par with Serafall in terms of power, the [Maou] who could literally freeze an entire country with ease.
And well, what happened next didn't disappoint him.
Grayfia didn't respond with words. Her hand rose, and her [Demonic Power] condensed into a blood-red magical circle that formed in front of her, taking the shape of a dragon. The air vibrated with the intensity of the spell, unleashing a devastating energy beam that tore through space with a deafening roar.
Kazuya, however, remained still, his white hair flowing in the turbulent wind, his blue eyes gleaming with an almost disdainful calm.
"Nice trick…" he murmured, his voice cutting through the roar of the attack like a blade.
When the energy beam was just a few meters away, Kazuya casually raised his hand, as if swatting a fly. With a single slap, he deflected the beam, the force of his movement splitting the attack into two streams that veered in opposite directions.
Boooommmmm!
The impact was cataclysmic: the two halves of the beam collided with the mountain range behind him, and the peaks exploded in a wave of dust and debris, split in half as if they were made of paper.
Grayfia widened her eyes, her composure momentarily shattered by shock, but before she could react, Kazuya vanished, moving at the speed of light. In the blink of an eye, his presence disappeared from her field of vision.
When Grayfia realized, he was already there, right in front of her. So close that she felt the air tear with his sudden arrival, like a sharp snap of compressed pressure between them.
Fast.
That was the only thought she could form as her body tried to react on instinct.
But it was too late.
Before she could respond, Kazuya drew his arm back, the muscles tensing under his pristine white shirt, and delivered a hook from below, aiming for Grayfia's stomach. The impact resounded like thunder, the air splitting with a sonic boom as the force of his fist pierced through the invisible armor of her [Demonic Power]. Her abdomen caved under the blow, the flesh compressing grotesquely, and a gush of blood spurted from her mouth, staining the air with crimson droplets. Her eyes widened, shock and pain blending into an expression of pure agony as her lungs collapsed, unable to draw breath.
But Kazuya didn't stop. Before Grayfia could even attempt to recover, his left fist came in a devastating arc, targeting her face. The blow was even more brutal, a collision of immense force that seemed to carry the weight of a mountain. The impact struck Grayfia's cheek with a crack, her facial bones shattering like porcelain under the pressure. Teeth flew in a bloody arc, mingling with the blood streaming from her mouth, and her once-flawless face deformed into a grotesque mask of torn flesh and broken bones. The force of the punch twisted her head to the side, her neck snapping audibly, and her body was flung like a broken doll, spinning uncontrollably through the air.
The collision was catastrophic.
The mountain couldn't withstand it. The rock crumbled under the impact with a dull roar, shattering like fragile glass. Fragments of the range flew in all directions.
Grayfia crashed among the rubble.
For a moment, only the sound of rolling stones could be heard.
Kazuya straightened, casually wiping his hand as if he had merely swatted an insect. His cold eyes turned to Sirzechs, who stood frozen in shock.
Sirzechs couldn't believe what he was seeing. He had barely glimpsed the boy's speed, but he couldn't react in time—and what was that monstrous strength…? But more importantly, Grayfia!!!! He quickly moved in panic toward her, reaching her side in the blink of an eye.
He knelt, his eyes wide with concern as they scanned his wife's condition. His hands, usually steady, trembled slightly as they touched her shoulder, avoiding the most severe injuries.
"Grayfia…" he murmured, his voice low, laden with an anguish he rarely let show. His eyes traced her disfigured face, her weak breathing, her chest rising and falling with difficulty.
The sight of her blood and broken bones twisted something inside him.
Then, the concern gave way to fury.
As he gently laid her on the ground and created a protective barrier, his eyes narrowed, and a crimson aura exploded around him, a wave of [Demonic Power] so intense that the ground beneath his feet cracked, sending fissures through the already devastated terrain. He rose slowly, his fists clenched so tightly that the veins in his hands stood out.
The friendly smile he always wore was gone, replaced by an expression of pure rage, his eyes glowing like burning embers.
He would kill him.
That thought crossed Sirzechs' mind like a steel wire, direct, cold, and unstoppable.
Slowly, a crimson aura began to rise around his body, dense and pulsating. The pressure was unbearable, almost physical, distorting the space around him.
The dimension itself began to tremble.
This was the true [Power of Destruction].
Everything that came near him—dust, rocks, even light—began to disintegrate at the touch of that energy.
Kazuya gave a faint smile as he began to release his energy, slowly and deliberately. A dark purple aura with crimson traces started to emanate from his body, spreading like a rising tide.
In the next instant, an invisible weight crashed down on the artificial world, as if the air itself had become denser, crushing everything.
Sirzechs felt the weight as if an ocean had fallen upon him. His thoughts raced, bewildered, as he tried to comprehend what stood before him.
"What… is this?! Is it… magical power?! No, it's far too different… I've never felt anything like this. It's not just the strength or the scale… There's a fundamental difference. It's so thick, so dense, it doesn't even seem like magical power. It's like an ocean crashing down on me… And most importantly, how did I not sense a hint of it from this boy before? This is too strange… He's dangerous… far too dangerous… I need to kill him quickly…"
Taking a deep breath, Sirzechs charged, moving at the speed of a crimson lightning bolt. As he moved, he launched a sphere of [Power of Destruction] toward Kazuya, a mass of black and red energy that consumed everything in its path, disintegrating rocks and distorting the air itself.
But Kazuya didn't retreat. His eyes narrowed, and he murmured two words in a low, focused tone: "Trace On."
He decided to use the spells he inherited from Senji Muramasa, which technically belonged to Shirou Emiya, the body the legendary blacksmith inhabited as a pseudo-servant.
A bluish light glowed in his hands, and the air around him vibrated with the activation of his magic. In an instant, he conjured [Rho Aias], the legendary seven-petaled shield, a mystical barrier that materialized in front of him as a glowing purple disk of energy, each petal pulsing with a force that defied destruction. The sphere of [Power of Destruction] collided with the shield, the impact unleashing a deafening roar that made the ground tremble and the remaining mountains crumble to dust.
The petals of [Rho Aias] shone brightly.
The seven petals represent the seven layers of oxhide. Each petal layer has the defensive power of a fortress wall, but it wasn't enough to stop Sirzechs' [Power of Destruction]… Quickly, each one was destroyed.
But Kazuya was already prepared for this. He knew his [Rho Aias] couldn't contain an attack capable of erasing souls, something truly troublesome to deal with. Fortunately, he had made some preparations. In a swift motion, he formed another "mudra"; the three middle fingers extended, while the index finger and thumb joined in a perfect circle. He channeled his magical energy through the gesture, activating a Magecraft spell he had developed himself.
As the mass of [Power of Destruction] broke through [Rho Aias], Kazuya raised his hand, now enveloped in a dark, pulsating aura, and extended it toward the attack. The moment his fingers closed around the energy, the impact ceased entirely.
The attack simply… ceased to exist.
A calm, confident smile appeared on his lips.
The spell he had just used granted a unique property to the magical aura enveloping his hand: it became a massive suction point, distorting the surrounding space and absorbing everything in its range, like a micro black hole. However, instead of destroying what it touched, his infinite magical energy "dissolved" everything absorbed, converting matter and power into pure energy for himself, which was rather useless…
Basically, this spell mimicked the events when a star reaches its end, resulting in a miniature black hole that consumes everything in existence. The suction force is immense, capable of consuming an entire continent easily if he kept his hand touching the ground for a few minutes. He called it [Ginnungagap Clutch], or more precisely, it was Skadi who helped him name it that way; Ginnungagap is the primordial void between fire and ice, the absolute nothingness before creation. He thought it was fitting.
Sirzechs widened his eyes, momentarily stunned, but he didn't hesitate, continuing toward Kazuya at his lightning speed. His hands, enveloped in black and red flames of [Power of Destruction], sliced through the air with rapid, lethal strikes, each punch carrying a force capable of erasing mountains from existence.
He launched a sequence of straight jabs, targeting Kazuya's chest, followed by an ascending hook that distorted the surrounding space, the [Power of Destruction] consuming the air in a radius of pure devastation.
But Kazuya dodged each strike with minimal movements, his body flowing like water.
One of Sirzechs' punches passed inches from his face, and he tilted his head at the last moment, the attack obliterating a rock behind him in an explosion of dust.
When Sirzechs attempted a spinning kick, charged with a wave of destructive energy that tore the ground in a straight line, Kazuya leaped back, using [Ginnungagap Clutch] again.
The wave of destruction was sucked into his palm, which he used to defend, dissolving into a pulsating void as if it had never existed.
After defending, Kazuya advanced, his right fist shooting forward in a direct punch aimed at Sirzechs' chest. The impact was like an explosion, the air splitting with a sonic boom. Fortunately, the Demon King blocked with his forearms, but the blow forced him back, the ground beneath his feet cracking into a crater.
Kazuya gave no respite, spinning his body in a low kick that struck Sirzechs' leg, forcing him to bend his knee. The Maou grunted, pain coursing through his body, but he retaliated with an explosion of [Power of Destruction], a black and red sphere that consumed the space in front of him.
Kazuya merely raised his hand, activating [Ginnungagap Clutch] again. The sphere was sucked into his palm, dissolving in the blink of an eye, while he advanced without losing his rhythm. An uppercut struck Sirzechs' chin, the sound of cracking bones echoing through the dimension, followed by his right fist smashing the Maou's cheekbone with a sickening crunch, blood flying in an arc. Another punch, this time to the stomach, made Sirzechs spit a gush of blood, his body folding like a broken marionette.
The Maou staggered, blood pouring from his mouth, but he tried to counterattack, launching a wave of destructive energy that tore the ground toward Kazuya. Kazuya dodged with a lateral leap, the attack passing by and reducing what remained of a mountain to ashes.
Kazuya seized the opening, advancing like a shadow. His knee collided with Sirzechs' abdomen, the impact doubling him over, the air escaping his lungs in a hoarse groan. Before the Maou could recover, Kazuya spun his body, delivering a spinning kick that struck Sirzechs' temple.
The blow was so violent that the Maou's neck snapped, and he was hurled into a pile of rubble, the impact creating a new crater that made the dimension tremble.
Blood streamed from Sirzechs' face, but he rose with a grim expression. How the hell was a human so strong? He narrowed his eyes, wiping the blood from his forehead and mouth, taking a deep breath… He clenched his fists, the crimson aura exploding around him, the [Power of Destruction] condensing into a black and red energy spear, so dense it distorted space. He launched the spear with a shout, the attack tearing through the air with a deafening roar, consuming everything in its path.
Kazuya merely gave a faint smile and, with the same calm, sidestepped the attack with a smooth motion.
BOOOOOOOOM!
The explosion that followed was devastating, more intense than any known nuclear bomb. Fortunately, the artificial dimension they were in was reinforced by Kazuya's infinite magical energy, capable of withstanding this level of destruction. Moreover, the dimension itself had a nearly infinite regenerative capacity, continuously restoring itself thanks to his inexhaustible magical energy source, so it wasn't surprising that the mountain range hadn't been completely obliterated yet.
But if they weren't inside that isolated dimension, Kazuya imagined the previous attack would have been enough to erase all of Japan from the map.
Seeing his attack completely dodged, Sirzechs gritted his teeth, frustration beginning to show on his face. He raised his hand, and dozens of orbs began to form above it, each the size of a volleyball, spinning slowly. They were so dark they seemed to absorb the surrounding light, like pieces of living night.
"Ruin the Extinct…" he murmured, almost through clenched teeth.
Without hesitation, he launched the orbs at Kazuya.
Kazuya moved at the speed of light, his body flowing with almost inhuman precision and flexibility. One of the spheres grazed his shoulder, enough to raise goosebumps, and exploded behind him in complete silence, obliterating a rock and leaving only emptiness in its place. Another sphere came from behind, fast and lethal, but he spun in the air with grace and delivered a precise kick. His foot, enveloped in vibrant magical energy, collided with the orb and violently deflected it to the ground. The impact opened a deep crater, swallowing the surrounding rubble like a hungry mouth.
During the fight, he noticed something interesting. By continuously coating his body with his magical energy, he could neutralize the [Power of Destruction]. It required some control; he enveloped Sirzechs' attacks with his magical energy each time he was hit. The attack consumed the enveloping energy almost immediately, but it gave him a moment to strike and redirect the attacks… and since his energy source was infinite, he could maintain this defense forever.
The "destruction" would only reach him if Sirzechs could do the impossible: destroy the very concept of infinity.
Kazuya continued to move with almost supernatural precision, his icy blue eyes tracking each orb of [Power of Destruction] launched by Sirzechs. His body seemed to dance between the attacks, each movement calculated, fluid, as if he could predict the trajectory of each sphere before they were even launched.
An orb came from the left, whizzing with a sound like the tearing of reality's fabric. Kazuya leaned back, the sphere passing millimeters from his chest, the destructive energy scorching the air and leaving a trail of emptiness. Another orb came from above, aiming for his head, but he spun his body in an acrobatic move, planting his hands on the ground and propelling himself sideways with a leap. The sphere hit the ground, creating a silent crater that swallowed rocks and dust, as if the space itself had been erased.
Sirzechs, his face contorted with frustration and fury, intensified the attack. More orbs appeared, now dozens, spinning in a chaotic pattern like a swarm of deadly wasps. The air around Kazuya vibrated with the crushing pressure of the [Power of Destruction], but he remained calm, almost indifferent. His white hair flowed in the turbulent wind of the dimension, and a faint, mocking smile curved his lips.
"Is that all?" he murmured, his sharp voice echoing across the battlefield. "I thought the great Maou would have something more… impressive."
Without waiting for a response, Kazuya channeled his magical energy. Once again, his dark purple aura, tinged with crimson, enveloped his body like a living, pulsating second skin. Then, he activated [Foot Saint], elevating his speed to a new level. He dodged the attacks with ease, almost effortlessly, as if he were always one step ahead of time.
While moving, he discreetly activated his [Imperial Privilege]. That ability was, without a doubt, something utterly absurd, as through his persistence, he could acquire any kind of impossible skill under normal conditions, such as the [Power of Destruction], even learning abilities that depend on divinity, let alone those tied to languages.
If something met the requirements, he could use his [Imperial Privilege] to acquire it.
In moments, he fully comprehended Sirzechs' [Power of Destruction] with absolute clarity. It was as if that power had always been his.
He didn't just learn it. He understood it, on the most intimate level, as if he had been born with it.
In an instant, Kazuya materialized his own [Demonic Bullets of Destruction]. The black spheres, now shaped by his will, collided with Sirzechs' in the air and disintegrated them effortlessly.
Sirzechs froze for a brief second. His eyes widened, incredulous, as he witnessed the impossible unfolding before him.
Was that the [Power of Destruction]?
"What—?" Before he could focus on it, countless orbs of [Power of Destruction] flew toward him, forcing him to defend with his own attacks. Sirzechs gritted his teeth, sweat dripping down his forehead as he tried to keep up with the boy's pace. He quickly decided he had to focus on this fight; it wasn't the time to be distracted by such things…
On the other hand, Kazuya seized the opportunity of Sirzechs' shock to attack.
He didn't hesitate.
His body shot forward like a bolt of lightning, moving at the speed of light, the air around him exploding in a sonic boom. Before Sirzechs could react, Kazuya was in front of him, his eyes gleaming with predatory intensity.
With a swift, brutal motion, Kazuya spun his body, his right leg slicing through the air like a blade. His foot, enveloped in a vibrant layer of magical energy, collided with Sirzechs' stomach in a devastating kick. The impact was like an explosion, the sound of the blow echoing like thunder as the air split around them.
Sirzechs spat a gush of blood, his eyes wide with shock and pain, his body folding over Kazuya's foot as if all the air had been forced from his lungs.
Swishhhh!
Boooooom!
The force of the kick was so immense that Sirzechs was launched backward like an arrow shot at the speed of light. His body sliced through the air, breaking the sound barrier multiple times, the impact creating a shockwave that shattered what remained of the surrounding mountain range. He crashed into a distant mountain, the impact so violent that the entire rock collapsed in an avalanche of rubble, dust, and fragments flying in all directions.
Kazuya straightened, his white hair flowing in the wind, his expression cold and disdainful. He wiped his hands, as if defeating a Maou were a trivial task. His eyes turned to the pile of rubble where Sirzechs had fallen, waiting to see if the demon still had the strength to rise.
For a moment, silence reigned, broken only by the sound of rocks still rolling across the devastated terrain. Then, a crimson glow emerged from the rubble. Sirzechs rose slowly, his body covered in dust and blood, his clothes torn, but his eyes still burning with unyielding fury. His aura of [Power of Destruction] exploded with even greater intensity, the air around him distorting as if reality itself were yielding to his rage.
"You…" Sirzechs growled, his voice hoarse but laden with determination.
The battle was far from over.
He raised both hands, and the [Power of Destruction] condensed into a series of blood-red magical circles that floated in front of him, each pulsing with energy that distorted the surrounding space. The first magical circle glowed brightly, unleashing a torrent of black and red spears, each charged with [Power of Destruction].
The spears sliced through the air with a deafening roar, moving in a spiral formation that seemed destined to pierce any defense.
Kazuya remained still, his blue eyes gleaming with an almost inhuman calm. He watched the attacks approach, the wind whipping his white hair. Then, with a slight blink, his eyes changed. His pupils contracted, and a supernatural glow took over his irises, now tinged with an ethereal blue laced with pinkish-red lines. He activated his [Mystic Eyes of Death Perception], allowing him to see the lines and points of death in everything around him.
"Trace On…" Kazuya murmured, his voice firm, his eyes focused.
A bluish light enveloped his hands, and the air around him began to vibrate, warping under the weight of the manifesting magic. In an instant, a blade took form: a katana of imposing presence and absolute cutting power; [Tsumukari Muramasa].
It wasn't just a sword. It was the realization of Muramasa's ideal, a blade that purged resentments, severed bonds, tore through fate, and even cut the invisible threads of causality. A weapon made to slice the very concept of karma.
But Kazuya knew that using it at its full potential meant walking toward self-destruction. He wasn't a god, after all. Just someone daring to wield a divine construct.
Tsumukari was, after all, a recreation of the legendary Tsumukari no Tachi, the ideal version of Kusanagi no Tsurugi, the sword extracted from the tail of the monstrous Yamata-no-Orochi by Susanoo-no-Mikoto. A colossal eight-headed, eight-tailed dragon that dominated valleys and peaks with its presence. A weapon created to face calamities, not to be wielded by human hands.
It was like a cannon made of glass: capable of destroying the enemy, but equally dangerous to its wielder.
But Kazuya didn't intend to use it in its complete form. However, even if he needed to activate it at full potential, he had already prepared some means to avoid his own destruction.
The spears of [Power of Destruction] were mere meters from striking him. Kazuya spun the katana with lethal precision, his [Mystic Eyes] revealing the lines of death crisscrossing each spear. With a single fluid motion, he sliced the air, the blade tracing a perfect arc that followed the invisible lines. The spears split in half, dissolving into fragments of energy that vanished like ashes in the wind.
The spears had been "killed."
Sirzechs didn't hesitate. He changed tactics, the magical circles around him spinning faster. This time, he conjured a storm of smaller spheres, each the size of a tennis ball, but dense enough to erase everything in their path. The spheres flew in a chaotic pattern, some exploding upon touching the ground, creating craters that swallowed rocks, while others converged directly toward Kazuya, like a deadly swarm.
Kazuya advanced, the katana dancing in his hands. His [Mystic Eyes] glowed brightly, tracking the lines of death in each sphere. He slashed with a speed that defied perception, each strike of the blade unraveling the attacks before they could reach him.
Sirzechs gritted his teeth, his frustration growing. He raised both hands, and the magical circles merged into a single, colossal one that floated above him like a black sun.
"Ruin the Extinct: Cataclysm!" he shouted as a wave of [Power of Destruction] erupted from the circle, traveling like a wind that consumed everything within a radius of kilometers. The air was swallowed by the black and red energy, the surrounding mountains crumbling to dust, the dimension's space trembling as if on the verge of collapse.
Kazuya, however, didn't retreat. His [Mystic Eyes] glowed even brighter, and he saw the lines of death. He spun the katana, and with a single motion, he sliced the air in front of him, the katana tracing an arc that followed the spell's lines of death.
The wave of [Power of Destruction] shattered like glass, split in half and dissipating in a harmless explosion of energy. The impact of the cut created a shockwave that shook the dimension.
Sirzechs widened his eyes, shock evident on his face. "Impossible…"
How could a human, no, how could anything, unravel an attack of that caliber with such ease?
Kazuya gave him no time to process.
Seizing the opening, he shot forward, katana still in hand. His [Mystic Eyes] tracked the lines of death on Sirzechs' body, vulnerable points pulsing like living targets. He spun the blade, aiming a precise cut at the Maou's shoulder, but Sirzechs reacted at the last second, raising a barrier of [Power of Destruction] that blocked the attack.
The blade collided with the barrier, sparks of energy exploding on impact, but Kazuya didn't stop. He spun his body, delivering a powerful kick to Sirzechs' stomach.
The force of the blow was overwhelming, his foot enveloped in magical energy amplifying the impact. Sirzechs spat blood, his body folding under the pressure, and was launched backward like an arrow, slicing through the air at the speed of light, until he crashed into the destroyed ground and bounced to a stop.
Sirzechs rose slowly, his body covered in dust and blood, his breathing heavy and irregular. He wiped the blood dripping from his mouth with the back of his hand, his crimson eyes still burning with a mix of fury and determination. Despite the pain coursing through every fiber of his being, he refused to yield. He was a Maou, one of the four kings of the Underworld, and he couldn't allow a human, no matter how powerful, to humiliate him like this.
Kazuya, on the other hand, walked toward him with provocative calm, the katana [Tsumukari Muramasa] resting casually on his shoulder, his [Mystic Eyes of Death Perception] deactivated.
He stopped a few meters from Sirzechs, tilting his head slightly, as if evaluating an opponent he already knew was defeated. A mocking smile curved his lips.
Feeling an increasing urge to punch the boy's face, Sirzechs charged, moving at the speed of a crimson lightning bolt. He threw a punch enveloped in [Power of Destruction], the air around the strike distorting with devastating energy. The attack was fast, precise, charged with the force of someone who knew they were fighting for their survival.
But Kazuya dodged with a minimal movement, spinning his body to the side as if dancing. The punch grazed past, obliterating a rock behind him in a silent explosion of dust. Before Sirzechs could recover, Kazuya swung the katana in a descending arc, the blade slicing through the air with a high-pitched hum. Sirzechs raised a barrier of [Power of Destruction] at the last second, but the force of the blow was enough to crack the defense, sending him staggering back.
Kazuya gave no respite. He advanced, the katana moving in a sequence of rapid, brutal cuts. Each strike was calculated, targeting vulnerable points with inhuman precision. Sirzechs tried to block, conjuring barriers and counterattacking with blasts of [Power of Destruction], but Kazuya seemed untouchable. He dodged the attacks with ease, each movement fluid and economical, while his blade continued to find flesh.
A cut opened a deep gash in Sirzechs' shoulder, blood gushing like a crimson fountain. Another strike tore across his chest, the blade slicing through his demonic armor like paper.
Sirzechs grunted in pain, his body trembling, but he tried to counterattack, launching a sphere of [Power of Destruction] at point-blank range. Kazuya merely tilted his head, the sphere passing centimeters from his face, and responded with a brutal kick to the Maou's stomach.
The impact was devastating. Sirzechs spat blood, his body folding in half as he flew backward, crashing into a rock that shattered under the force. He fell to his knees, gasping, blood dripping onto the cracked ground of the artificial dimension. His vision was blurred, his lungs burning with each breath, but he forced himself to stand, leaning on a broken rock.
It seemed he had no choice…?
The boy had proven to be even stronger than he had imagined.
Sirzechs took a deep breath… and then unleashed the power he had kept contained within himself.
The world itself shuddered and then seemed to scream in pure terror as Sirzechs' aura grew ceaselessly.
In an instant, he was engulfed by a deep crimson cocoon, radiating shockwaves of raw power, reverberating not only across the battlefield but throughout the entire territory protected by the barrier… perhaps even beyond.
It wouldn't be surprising if even humans, usually oblivious to the supernatural, could feel it in its full intensity.
It was as if an entire ocean had risen above Kazuya and the entire battlefield.
A sharp crack cut through the air, drawing his attention. He turned his gaze to the center of the storm of pure power.
The cocoon began to open, with intense red light escaping through the cracks, flooding the surrounding forest with an indescribable otherworldly energy.
Then, with the resounding sound of shattering glass and a blinding flash of crimson light, the cocoon was torn apart. The resulting explosion unleashed a massive shockwave that swept through entire forests and disintegrated mountains, all with just the pressure of its presence.
In the space once occupied by Sirzechs and his cocoon, something emerged.
It had the vague shape of a human but was, in truth, an absurdly dense cluster of [Power of Destruction], gathered around that humanoid silhouette.
But it was much more. Far more than any being could comprehend.
Thus, it could only be described as "something," for no word, in any living or dead language, could capture the essence of what now stood there.
"Feel honored, human. This is the first time in three centuries that I assume my true form. The only other to receive such an honor was Rizevim Livan Lucifer."
The "thing" spoke with a terrible mockery of Sirzechs' voice. Still, its voice sounded crystalline, even above the roar of the collapsing world around it. The space-time around it distorted, losing its cohesion.
The sounds that normally came from the Crimson Lucifer's throat were soft, calm, almost melodious, befitting someone who had inherited the title of the Devil known as the Seducer of Humanity.
But the voice of that entity… was cold. Dark. Deep. A harbinger of calamity. Each syllable carried a supernatural weight that chilled to the bone.
It shouldn't even exist.
This… was the [True Form] of Sirzechs Lucifer.
It was the [Incarnate Aura of Destruction], the true manifestation of his being, in which his body became a condensed core of [Power of Destruction] with a humanoid appearance. In this form, his power radiated explosively and uncontrollably, defying any attempt at containment.
Sirzechs, in this form, was so far beyond the original Lucifer that he was almost a separate entity. A being capable of confronting and defeating Hades, one of the Ten Strongest Beings in the World.
And even in the face of a monster that would make the gods themselves tremble in fear…
…the human before it merely smiled.
Kazuya took a deep breath, his icy blue eyes now filled with a seriousness he hadn't shown before.
He murmured, activating his personal ability absorbed from Ddraig.
"Boost."
A wave of power exploded from him, doubling his strength in an instant. The ground beneath his feet cracked, and the air vibrated with the intensity of his energy. He repeated the command, each word echoing with authority.
"Boost. Boost. Boost. Boost. Boost. Boost. Boost. Boost. Boost."
With each repetition, his power grew exponentially, a cascade of energy that made the dimension itself tremble.
Ten times.
Tenfold power.
The air was so dense it seemed solid, and Sirzechs, even in his [True Form], felt a shiver run through his being, something he hadn't felt in centuries.
Kazuya decided to end this fight quickly, murmuring.
"Balance Breaker — Ain Soph Aur."
The world was engulfed by an explosion of [Holy Light].
A radiance so pure and overwhelming that it seemed to purify even the concept of destruction emanating from Sirzechs. The light poured from Kazuya like a rising sun, dissolving shadows and consuming the darkness around him. His white hair transformed into golden strands, flowing like living flames, glowing with a divine aura. An ethereal crown, made of condensed light, materialized above his head. Behind him, twelve white wings unfolded, each feather radiating energy so intense that the surrounding space seemed to bow in reverence.
This was his [Balance Breaker].
Essentially, [Ain Soph Aur] removed all previous limitations of his Sacred Gear. While active, he could rewrite the minds of any supernatural race, no longer limited to just humans, though it wasn't permanent, and the stronger the person, the less time it took for them to break his mental manipulation. His powers over "light" were also fused with the holy power of the "blood" of his Sacred Gear, made from the nails bathed in Christ's blood, creating something he called [Holy Blood Light], similar to Uriel's "Holy Fire" and Baraqiel's "Holy Lightning." He could use it for countless purposes.
But the main ability of his Sacred Gear was that it granted him absolute defense, coating his body in a defensive membrane that protected him from all types of phenomena. With anti-physical, anti-magical, anti-temporal, and anti-accidental attributes, his already robust bodily defense was elevated to an even higher level.
He looked at Sirzechs in his true form, who seemed surprised to see his new form.
Without warning, the ground beneath Sirzechs trembled, not from a physical impact but from something deeper, as if reality itself were being twisted. He felt a chill run down his spine, a sense of imminent danger he couldn't explain. Before he could react, a sharp pain erupted in his chest, as if something were tearing his flesh from the inside out.
With a muffled scream, Sirzechs lurched forward, his hands clutching his chest. Suddenly, a metallic clank echoed, and a bolt made of "light," long and sharp, burst from within his torso, piercing his skin and demonic armor like paper. Blood gushed, staining the ground red, as the Maou's eyes widened in shock and agony. Before he could process what was happening, another bolt appeared, this time in his shoulder, tearing through muscle and bone with grotesque precision.
"What… what kind of power is this?!" Sirzechs roared in pain, his voice distorted by a mix of fury and fear. His eyes widened, staring at the bolts in his body made of holy energy, the endless burning and pain. "This… this holy energy is on the level of the Four Archangels?!"
Kazuya didn't respond immediately.
"You said I should feel honored to see your true form…" he said, his voice now laden with a divine resonance, echoing as if coming from every corner of the dimension. "But now, Sirzechs Lucifer, it is you who should feel honored. You are the first to witness [Ain Soph Aur], the pinnacle of my Longinus."
Sirzechs gritted his teeth, the [Power of Destruction] in his body roaring in defiance. After great effort, he managed to destroy the [Holy Bolts] that had appeared in his body. If it weren't for his [Power of Destruction] automatically containing the holy power and destroying it despite the pain, he could be dead now.
With a simple gesture, Kazuya unleashed a nail made of [Holy Blood Light] that shot toward Sirzechs, moving at a speed that transcended the concept of time. The Maou tried to counterattack, launching his vortex of [Power of Destruction], but the moment the light collided with the darkness, the result was unexpected.
The nail made of red light swallowed the [Power of Destruction], dissolving it as if it were a shadow before dawn.
The nail continued its trajectory, striking Sirzechs squarely in the chest.
The impact was cataclysmic. Sirzechs was launched backward.
The [Holy Blood Light] burned his true form, corroding the aura of destruction like acid on metal. He fell into a crater, his body smoking as the pain made him groan. If he hadn't been weakened by the bolts before…
Sirzechs, even with his body smoking and excruciating pain burning every fiber of his [True Form], gritted his teeth and rose from the rubble. The ground beneath his feet trembled, cracking further with the sheer force of his crimson aura, pulsing like a living heart, distorting the space around him.
With a roar, he shot forward, moving at the speed of light, the ground of the artificial dimension cracking under his feet. His [True Form] should destroy anything it touched… He threw a direct punch, the air exploding in a shockwave as his fist sliced through space, aiming for Kazuya's chest.
Kazuya, however, dodged with a minimal movement, spinning his body to the side as if dancing. The punch grazed past, the destructive force crushing a mountain behind him in a silent explosion of dust. Before Sirzechs could retract his arm, Kazuya counterattacked, his right fist enveloped in [Holy Blood Light] colliding with the Maou's stomach. The impact was devastating, a sonic boom echoing as Sirzechs' aura shattered like glass.
The Maou spat blood, his body folding, but Kazuya didn't stop. Grabbing Sirzechs' arm, he pulled him downward, delivering a brutal knee to the Maou's face. The sound of breaking bones echoed, Sirzechs' nose and cheek deforming under the impact. Blood gushed, staining the air, as Sirzechs staggered back, dazed. He tried to retaliate, spinning his body for a spinning kick enveloped in [Power of Destruction], but Kazuya blocked with his forearm, the [Holy Blood Light] neutralizing the destructive aura as if it were nothing.
With a swift spin, Kazuya landed a left hook on Sirzechs' chin, the blow so violent that the Maou was launched upward, spinning uncontrollably.
Sirzechs' eyes widened, incredulous.
"How…?" He didn't have time to finish the question.
Kazuya vanished in a blur of light, moving so fast that the space itself seemed to bend around him. Before Sirzechs could react, he reappeared in front of him, mere centimeters away, his right fist enveloped in [Holy Blood Light] glowing like a miniature sun.
The punch struck Sirzechs' chest with a devastating impact. The sound of the blow echoed like thunder, the air splitting in a shockwave that shattered the remaining mountains around them.
Sirzechs' [True Form], which should destroy anything that touched it, couldn't withstand it. The [Holy Blood Light] burned through the [Power of Destruction] aura, corroding it like paper. Sirzechs' chest caved, the impact crushing bones and internal organs, blood gushing from his mouth in a crimson arc.
He was launched backward, his body spinning uncontrollably in the air, but Kazuya gave no respite.
Before Sirzechs could hit the ground, Kazuya appeared above him, moving at a speed that defied perception. He spun his body, delivering a descending kick that struck the Maou in the stomach. The impact was so brutal that the ground of the artificial dimension opened into a kilometers-wide crater, the sound of the blow reverberating like a nuclear explosion. Sirzechs spat another gush of blood, his body folding in half as he crashed into the rubble, the force making the dimension tremble.
Kazuya descended slowly, as one of his twelve pairs of wings dissolved into particles. He let out a sigh as he cracked his neck.
His Balance Breaker granted him twelve miracles, accounted for by the wings formed behind his back. He could choose what these miracles would be used for, and the one he had just used was to add the characteristic of "nullification and corrosion" to his [Holy Blood Light], allowing it to nullify and burn like acid Sirzechs' [Power of Destruction]. This enabled him to defend against the Maou's attacks and strike without fear of being destroyed by a power that caused destruction at the atomic level, capable of even erasing someone's soul.
The drawback was that the "miracle" he used only persisted while he kept his Balance Breaker active.
As he sighed, Sirzechs rose again, charging toward him and throwing a punch, the air exploding in a shockwave, but Kazuya didn't move. He waited, his fist glowing brighter, until Sirzechs' attack was mere centimeters away. Then, with a speed that transcended perception, Kazuya unleashed his [Shining Punch].
The impact was cataclysmic.
Kazuya's fist collided with Sirzechs' face, the [Holy Blood Light] erupting in an explosion of energy so intense that the artificial dimension's space seemed to scream. The [Power of Destruction] aura enveloping Sirzechs shattered like fragile glass, unable to withstand the overwhelming force. Half of the Maou's face was obliterated, bones shattered, flesh and skin disintegrated in an instant, blood gushing in a grotesque arc.
Sirzechs' body was launched backward like a broken marionette, slicing through the air at the speed of light. He crashed into a distant mountain, the impact so violent that the entire rock collapsed in an avalanche of rubble, dust, and fragments flying in all directions. The sound of the collapse echoed like thunder, the dimension trembling under the force of the blow. Sirzechs fell among the debris, his body reverting to his humanoid form, the [True Form] completely dissipated.
At that moment, his battered body was revealed.
His skin, once pristine like royal porcelain, was now covered in deep burns, raw flesh exposed in various places. Deep cuts marked his torso and arms, and holes as large as baseballs, from which blood flowed in thick, dark streams, soaking his tattered tunic.
Half of his face had ceased to exist.
And yet… he forced himself to stand.
Trembling, wavering, his knees threatening to give way every second. His feet dragged on the uneven ground, and his entire body seemed to scream for rest, or perhaps, for mercy. But his eyes, even with only one remaining, still glared at the opponent before him.
There was no hope in that gaze.
Not for lack of courage. Sirzechs was, after all, one of the most powerful beings in the entire Underworld. But even his vast power… even his true form… was no match for the monster standing before him.
And in that moment, for the first time in centuries, he knew.
He couldn't win.
As he thought this, Kazuya, who had deactivated his Balance Breaker and his [Boosts], appeared before him like a ghost. Without ceremony, he reached out and grabbed Sirzechs by the collar of his ragged tunic.
The demon's body swayed like a loose puppet, his feet barely touching the ground.
And then, the first punch came.
Dry. Fast. Precise.
Kazuya's fist sank into Sirzechs' remaining cheek with enough force to break bones. The sound of the impact echoed like muffled thunder, and the Lucifer's face was thrown back, still held by the collar like a sack of flesh.
Another punch.
Then another.
And another.
Each blow was casual, as if he were beating a punching bag, not one of the most powerful beings in hell. Blood splattered in the air, painting the dimension's ground with scarlet streaks.
Kazuya spun and delivered a precise kick to the Devil's stomach, making him bend involuntarily with a choked sound. Another kick, now to the face, sent Sirzechs crashing to the ground, but Kazuya pulled him back by the collar before he could fall, only to continue without a word.
Another punch.
Another. And another.
Sirzechs' face was already too disfigured when he stopped.
Kazuya let out a faint sigh, almost as if finishing a workout.
Finally, he released the Devil's collar.
Sirzechs fell like a corpse, arms spread, chest rising and falling with effort.
Kazuya looked down at him, his hands still dripping with blood.
"And now…? What do I do with you and that bitch?"
He raised his hand to his chin, thoughtful, his brow slightly furrowed as if choosing between two brands of wine. Then, as if remembering an irrelevant detail, his eyes turned to the horizon—or what remained of it.
Two kilometers away, among the ruins of mountains that no longer existed, Grayfia's familiar, weak, and wounded aura flickered like a candle about to go out. She was buried under rubble.
Kazuya lazily raised his hand.
A subtle scream in the air, and then gravity violently distorted. A compact, pulsating [Blue] appeared before him like a silent implosion. The rubble trapping Grayfia was sucked up like dust in a whirlwind, and her unconscious body flew through the sky, straight into Kazuya's hands—unconscious, wounded, her clothes in tatters.
He held her by the arm as if holding a broken doll and dropped her beside Sirzechs.
The original plan was to defeat Sirzechs to gain recognition in the supernatural world, but after what he said about the death of his older sister, which likely had something to do with him… He simply felt that this wasn't enough.
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(A/N: Guys, that was the fight, it was kind of fulfilled because I wanted to make Kazuya fight more seriously considering that Sirzechs technically has the power to destroy the world, and about the Marble Phantasm, Kazuya knows due to [Magecraft: Ex] which gives him knowledge about all the Magecraft that exists, even such a thing that only appears in Elementals or like in our favorite vampire from Tsukihime. Anyway, I hope you liked it, the chapter has 10k words, give me suggestions on what to do with Sirzechs and Grayfia, I have some ideas, but I want to hear yours.)