HxH: I Will Be Supreme

Escape?

Oboro's words cut Muzan to the core, striking him with the force of his deepest fears.

The demon king's retreating feet froze mid-step. Why should he run? After lurking in the shadows for centuries, hunting inheritors to harvest their soul power, hadn't all of this been for this very moment?

The thought ignited something fierce within Muzan's chest. His expression twisted with sudden fury as the frail old man before him merged with the vague figure his consciousness had observed in the past.

"You're the one who should escape," Muzan snarled.

His enhanced senses detected the decay eating away at Oboro's flesh and blood. By any measure of human lifespan, the old man had precious little time left. In such a weakened state, he dared to stand against the demon king?

The floating platform beneath their feet suddenly erupted. Walls of writhing flesh and blood burst from the ground on all sides, sealing them in a grotesque arena. Countless bone spurs emerged from the pulsing walls like ivory spears, all aimed at Oboro's heart.

"The power of the soul isn't something only you possess," Muzan sneered as he watched the old man's expression shift. Pride colored his voice as he prepared for the killing blow.

"Really?"

Oboro's eyebrows rose with mild amusement. When his deep, ancient eyes met Muzan's, they seemed to transform into black holes with a terrifying gravitational pull, as if they could drag the demon's very essence from his body.

Terror struck Muzan like lightning.

No one understood Oboro's true horror better than Muzan, who had touched the power of the soul. Within the old man's seemingly frail form, Muzan sensed an energy so immense it defied comprehension. This was his "breath of the soul": a soul fluctuation beyond mortal description.

But Oboro wasn't releasing it as pressure or a weapon. He was simply lifting the veil that concealed his soul's true nature, allowing Muzan to witness it directly.

The feeling was overwhelming. Moments ago, Muzan believed himself victorious with his newly acquired musket. Suddenly, he realized his enemy commanded an entire army equipped with advanced weaponry and battle-hardened experience.

"Impossible..." Muzan's voice cracked. "How can a human soul be so powerful? How can such magnitude be contained in a ridiculous human body?!"

This transcended any metaphor of a small horse pulling a massive cart. Muzan felt himself plunging into an Arctic abyss.

For several heartbeats, he stood paralyzed. When he finally looked down, shock coursed through him. For the first time since his transformation into the demon king, his legs trembled uncontrollably.

Could he not overcome this primal physiological response to fear?

This revelation shattered his understanding. After discovering soul power, Muzan had learned a fundamental truth: the body serves as the soul's container. Even if Oboro had created soul techniques, his strength as a human should have been limited by physical constraints. Meanwhile, Muzan possessed the body of the demon king. This logic had given Muzan the courage to face Oboro.

However, the scene before him obliterated his assumptions completely.

The magnitude of their soul difference was staggering. Oboro needed only a thought to activate soul pressure that would annihilate Muzan's essence instantly, leaving behind nothing but an empty shell.

"Since arriving in this world, you're the first person to truly witness my trump card," Oboro said calmly.

Arriving in this world?

The phrase made Muzan's pupils contract sharply. The old man suddenly seemed wrapped in layers of impenetrable mystery.

"Who...what are you?" Muzan forced the words through gritted teeth, struggling to maintain his composure.

"The soul is an incredibly profound subject," Oboro replied with a gentle smile. "When you must cross the river by feeling stones, reaching your current level is quite admirable."

Setting aside everything else, Muzan's soul attainments were barely entry-level, yet he stood out remarkably among the inhabitants of this world who couldn't even perceive souls.

"I'm quite satisfied with your progress."

The demons evolved from inheritors relied purely on willpower—evolving through mutual devouring. They gained power by consuming other demons, blending flesh and blood and accommodating multiple consciousnesses within single bodies.

Similar to Teshimagagaji, who attacked the shogunate, they could perform various blood demon arts, rather than being limited to one type. They gradually returned to their ancestral roots, approaching Muzan's level.

Following this trajectory, the evolutionary endpoint for all Inheritors was to become individual Muzans—or perhaps to surpass him entirely.

This represented an improvement in power levels rather than new branches growing on the original system's skill tree.

However, Muzan had achieved something different.

Oboro observed the towering flesh walls and razor-sharp bone spurs protruding from his opponent's form. In the original timeline, Muzan hadn't possessed such abilities. While fighting Tanjiro and the others, he could alter his physical form through cellular manipulation—splitting, proliferating, and transforming—but he couldn't fundamentally separate himself from his body.

Now, however, he could release and activate blood cells in spaces completely external to himself. This wasn't just another blood demon art technique.

All blood demon arts relied on physical energy alone.

But now, the soul could be utilized as well.

With soul and flesh as dual sources, this resembles how Oboro developed soul-based Nen abilities in the Hunter x Hunter world. He had brought soul power to this realm, where Muzan had discovered and studied it.

This method bore the shadow of Nen techniques, reaching the threshold of a higher world's power system.

Through the soul's will, cellular abilities could be transformed.

If this knowledge were to spread among demons in the future, like how breathing techniques influenced the Demon Slayer Corps, then this power would become far more terrifying than blood demon arts.

Although Muzan ruled as the demon king, his strength remained at "human" levels in the original work, at least according to Oboro's experience.

Oboro had gifted breathing techniques directly to the Ubuyashiki clan.

However, soul power could not be handed down directly to demons. He could only grant it to specific inheritors, and the results would be ineffective. Demon power structures differ vastly from those of the Demon Slayer Corps. They are too scattered, and even the inheritors lack unity. If demons who had mastered soul power died, their knowledge died with them, wasting Oboro's soul energy.

When Doma and Kokushibo appeared before him, Oboro noticed the difference in these two Upper Moons.

Clearly, Muzan had shared fragments of his weak soul power with them.

Muzan served as Oboro's predetermined "embryo."

All of Muzan's schemes and actions fell within Oboro's calculations.

This way, Muzan would bear the soul consumption cost, not Oboro himself.

Oboro's soul appeared overwhelmingly powerful only to Muzan; it wouldn't seem so terrifying in higher worlds. This was because he had deliberately weakened his soul to achieve interdimensional travel.

His purpose in traversing different worlds was to allow his soul to grow and develop again through supreme will. The system's functions served as the actual manifestation of this process.

Therefore, Oboro treasured his soul immensely.

Even when striking deals with the Demon Slayer world, he wouldn't sacrifice his interests selflessly.

Xiaoshu had begged him precisely because he possessed higher-world power.

Improving this world's power system required relying on him and sharing higher world abilities. This was the only fundamental method for strengthening the realm.

Breathing techniques, soul power, and combat skills were involved.

The Demon Slayer Corps and the Kamado clan represented breathing techniques.

Muzan embodied the soul.

Gyutaro represented combat skills as a specific catalyst.

Given sufficient time and proper circumstances—meaning the right general environment—these three powers would expand and evolve infinitely over generations.

They would form rain and fertilizer, nourishing all the "seeds" throughout the world.

By controlling everything from behind the scenes, Oboro transformed ordinary civilians in this world.

The demon factor enabled many common people to develop ways to deal with demons.

The official army began hunting demons systematically, and most people qualified to receive these powers.

Otherwise, Oboro wouldn't have spent years wandering, selecting targets, using experience cards, and earning the title of "God."

When soul power, breathing techniques, and combat skills became widespread in the Demon Slayer world, the realm would ascend to a higher level.

This had been Oboro's true mission all along.

Connecting all the scattered dots and lines into a unified whole was his genuine plan.

Now, the overall situation was decided.

What remained was simply time.