My Monster Evolution in One Punch Man

"Face the storm!"

With a sharp shout, a rapidly spinning wall of wind surged to life before Hansen. A swirling vortex of air currents materialized, forming a barrier of wind that roared with momentum. Streams of azure gusts cascaded like waterfalls, stretching across the space in elegant arcs. The scene was nothing short of majestic.

Its true defensive power remained untested, but in terms of visual flair, it was at its peak.

After rounds of experimentation, Hansen had finally grasped the diverse applications of wind manipulation. He could now amplify his physical abilities, strengthen his strikes, and, in a moment of inspiration, fuse them with his "Scorching Blast," drastically improving both its velocity and piercing force.

With further control over airflow, he managed to lift his heavy frame off the ground. He hovered awkwardly in mid-air, supported by swirling currents beneath him. Just maintaining that fragile levitation generated a fierce storm around him.

Countless unseen blades of wind slashed through the lair's interior, carving the stone into jagged shapes and hurling debris in every direction. His flight was shaky and required great effort, but Hansen found satisfaction in the progress.

After all, he had advanced from zero to one. That first milestone signaled the beginning of his ability to fly.

The skill "Swift Wind" had significantly enhanced his agility and opened up more flexible combat strategies. Yet now, something far more exhilarating demanded his attention.

"Monsterization!"

For someone like Hansen, who had transmigrated into this world, reclaiming his full human form was no small matter. Shedding his strange, half-monster appearance and returning to a natural, human shape carried immense personal value.

He focused his thoughts and activated the ability.

"Monsterization: Human Form Transformation!"

Crack!

Crack!

Crack!

A new and powerful force, completely different from before, surged through his body. The first sensation was the harsh crunch of bones shifting, followed by the constriction of his exoskeleton.

In an instant, the dense armor that once covered him began to emit soft grinding noises. Rather than breaking, it writhed and receded like a living organism, swiftly withdrawing beneath his skin.

His towering frame, which stood at over three meters, began to shrink rapidly. Muscles coiled and bones restructured, reshaping him under the influence of an unknown power.

In just a few seconds, the terrifying presence he once carried vanished completely.

Standing in his place was a young man around 190 centimeters tall, radiating a commanding and cold charisma.

His figure was lean but defined, with muscles sculpted to perfect proportions. His chest was broad and solid, his biceps bulging with coiled strength.

Short, jet-black hair lay neatly across his head. His facial features were sharp, symmetrical, and chiseled. A high nose bridge, narrow eyes, and thin lips created a visage so handsome it would make most men self-conscious.

If not for the occasional crimson glint in his eyes and the faint monster-like aura still emanating from his bare, well-built body, he could easily be mistaken for a first-class idol. He even surpassed the most attractive celebrities from his previous world.

This was Hansen's true face, or at least closest to one, before he came into this world.

He instinctively reached up and touched his cheek, his eyes fixed on the unmistakably human knuckles of his hand. For a brief moment, he stood still, lost in a daze. Though only a short time had passed since he first arrived in this world, it felt as if an entire lifetime had unfolded. Regaining a human body after everything he had been through stirred an indescribably complex emotion deep within him.

"I may have stopped being human to gain power, but this feeling... being human again isn't so bad."

As those thoughts settled, Hansen began to notice several problems with his current state. While in human form, his strength, speed, and durability had plummeted. It felt as though invisible restraints had been locked onto his power. Every movement felt heavier, as if the very essence of his abilities had been sealed away.

In this weakened state, he wouldn't stand a chance against a typical Tiger-level monster, much less anything approaching the Demon level.

"And that's not even the worst part."

After a brief sprint and throwing a few test punches, he exhaled deeply and assessed the situation with a serious expression.

"The copied abilities were already weaker than the originals. Now, after transforming into this human form, not only has my strength taken a massive hit, but even maintaining the form feels unstable."

Hansen shook his head.

"Any hero ranked A-Class or above would immediately sense something off about me... and I can't completely suppress this monster aura either."

Hansen frowned slightly, drawing a quiet conclusion.

"Just as I suspected. Level 1 'Monsterization' is still far too limited."

To perfectly integrate into human society and move among people undetected, he needed to improve this ability, maybe even push it to evolve completely.

The moment he deactivated the form and reverted to his monster state, an unexpected sensation rippled through his body.

Because the system provided copied abilities with innate mastery, Hansen was instantly aware that something was different. Alongside the expected transformation from monster to human and vice versa, he sensed another option within the skill, a second activation of "Monsterization" while already in his monster form.

Stunned by this unexpected feedback, Hansen stood in silence for a beat.

"...Is this a bug?"

But after thinking it over, he shrugged it off.

Most people would have unlocked "Monsterization" from their human state. But he had been a full-fledged monster from the beginning, and the system granted him the ability in that form. In a world governed by such bizarre logic, this anomaly didn't feel out of place.

"...Well, no harm in giving it a shot."

Since it didn't cost him anything to test it, there was no reason to hesitate.

Without any urgency, Hansen triggered the ability again.

This time, instead of reverting back to a human form, he initiated a second monsterization, building upon his already-transformed body.

Boom!

A devastating pressure burst from his form. In that instant, his energy erupted violently, surging to new heights.

His towering, black form expanded once again. Crimson magma-like veins across his exoskeleton flared, blazing with intense, blinding light.

In the blink of an eye, he had ascended several tiers. His power skyrocketed, soaring straight to the peak of Demon-level.

Overwhelming. Ridiculous. Absolute power.

Back in Hansen's domain:

As the cavern floor and rocky walls suddenly trembled, the countless Wolf-level monsters stirred in confusion. But among them, Fang and the other Tiger-level monsters turned their gazes sharply toward the source of the disturbance: the heart of Hansen's lair.

"Lord Hansen... seems to have gotten stronger again?"

"I'm starting to get used to it, but this is still way over the top..."

"For real. It's like he just eats and drinks and levels up instantly..."

"..."

Within the dim underground chamber, the monsters exchanged whispers, their voices tinged with awe and disbelief.

Back inside the lair, Hansen himself stood in stunned silence.

"Holy crap...!! This power!!!"

A colossal force had erupted within him, rising as if from an infinite wellspring. It surged through every fiber of his body, untamed and exhilarating. Despite the tremendous increase in muscle mass and sheer energy, he felt no strain, no tension, just overwhelming strength.

The sheer absurdity of it left Hansen feeling dazed. He had become stronger. Again. Just like that.

What kind of absurd cheat was this supposed to be?

But as he thought it through, a strange logic began to settle in his mind. Perhaps this was simply the nature of monster evolution, twisted, erratic, and completely unnatural.

No grueling training routines. No years of refining techniques. All it takes is one chance, and your disaster level could skyrocket.

Your strength could surge instantly, skipping all traditional growth.

This was the true horror of monsters.

They didn't need discipline. They didn't follow a path of mastery. A single mutation, a single transformation, and their power would become something incomprehensible.

Somehow, he had stumbled upon a transformation-based ability that included a hidden second phase. And that accidental discovery now felt like a stroke of genius.

"Not even three days since I became a monster... and I already have a second transformation like a proper final boss."

He grinned to himself.

"Let's call this move... Monsterization, Stage Two!"

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