I Spread my Genes to Level Up in the Apocalypse

Bang!

As Ray's punch connected, the cat's body bent unnaturally, absorbing the force of his punch and landing lightly on the ground with grace.

"You..." Ray muttered, staring at his fist. It felt like he had hit jello instead of a solid object.

Just then, the Raven moved with terrifying speed, and Argos' great longsword slashed toward the back of the undead cat.

This time, the cat couldn't react in time; its focus was entirely on Ray.

The sword slashed through, leaving a large, gaping wound, but it couldn't cut all the way through due to the intense blue flames that melted the blade.

Argos' sword disintegrated into nothingness.

The furious undead cat turned its gaze to Argos and "meowed" again, its voice filled with wrath.

Ray's eyes widened as he watched Argos slowly turn transparent, fading out of existence entirely within seconds.

"His soul... is wiped out?" Ray muttered, shock coursing through him. He could no longer feel Argos' presence; the undead warrior had completely vanished.

Ray's gaze snapped back to the undead cat, noticing that it seemed weaker now.

The patterns on its skin had faded significantly, and the overwhelming aura of suppression it once had was now almost gone, almost becoming comparable to Raven now.

"Chance," Ray thought, his eyes lighting up.

He lunged forward in a powerful charge, obliterating everything in his path as he unleashed another forceful punch with full strength.

Boom!

The undead cat, unable to keep up with Ray's speed, took the full impact of the blow. Despite the blue flame armour covering its small body, it couldn't escape its fate.

At that moment, time seemed to pause as Ray's eyes caught sight of the undead cat, noticing something unexpected—a smile forming on its ferocious, red-skinned face.

"Kiyko sincerely thanks you, nya," the cat's voice echoed in his ears and time seemed to be resumed as it was smashed to bits on the ground.

His ears twitched when he heard it.

"Am I hearing things?" Ray muttered, a strange expression crossing his face. He looked at the remains of the undead cat, feeling a pang of heartache.

…

"Kiyko, we're going to be fine," the little girl whispered, tears streaming down her face as she clutched the small kitten tightly in her arms.

Outside the door, her father's shouts grew louder, punctuated by the sound of something crashing against the wood.

"You little bitch! Your mother abandoned me while I was a soldier and went off on her own. Why? Why did she leave?" he bellowed, kicking the door open.

His face was flushed, reeking of alcohol, and filled with a twisted rage.

The sight made the girl cower even more, trembling under the table.

Her tiny hands clutched the kitten closer, desperately seeking comfort.

"You're that vixen's daughter," her father spat, pulling off his belt with a cruel sneer. His eyes glinted with a murderous intent as he raised the belt high and brought it down with vicious force.

"Ahhh—" the little girl screamed in agony as the belt lashed across her skin, the pain searing through her small body.

"Meow…" Kiyko, the kitten, looked at the crying figure of the little girl, its heart seeming to break at the sight. Without hesitation, Kiyko extended its tiny paws, revealing sharp claws, and leaped at the man's face.

"Let go of me, you fucking cat!" the father roared in fury, closing his eyes as the kitten's claws scratched across his face.

Enraged, he grabbed the back of the kitten's neck and flung it away with a brutal swat.

Kiyko hit the wall and then the ground, landing with a weak thud. It lay there, struggling to move, its small body battered and broken. Yet, despite the pain, Kiyko's eyes still burned with fury as it glared at the man.

"No, Kiyko…" the little girl sobbed, tears flowing uncontrollably as she watched the kitten's struggle. But her cries only seemed to fuel her father's rage.

With unrelenting rage, he continued to beat the little girl with his belt, each lash more brutal than the last, until her sobbing finally ceased, and she slipped into unconsciousness, her small body limp and motionless on the cold floor.

"Hmph, this little brat. Once she's older, I'll sell her to those generals. She'll at least be useful to me for getting some money," the man muttered coldly, showing no mercy as he tossed the little kitten out of the house and went to sleep, uncaring of the suffering he had caused.

At this time outside, the world was undergoing a strange and terrifying transformation.

The air was thick with radiation from the war and destruction, its properties altered in ways no one could predict.

The earth itself seemed to gladly adapt to this new change in the radiation.

Kiyko, the little kitten, lay weakly on the ground where she had been thrown. Slowly, she opened her vertical pupils, but something was terribly wrong.

Her body began to change rapidly, twisting and contorting in ways that defied nature. The radiation seeped into her, burning away her fur until her skin became a vivid, unnatural red.

Kiyko cried out in pain, her small body writhing on the ground.

The radiation was merciless, draining the blood from her veins, turning her screams into desperate, agonised wails that echoed into the night.

As the night wore on, Kiyko's cries grew louder and more desperate, a haunting cry of the kitten that carried through the darkness.

The kitty grew in size, reaching the average height of a normal cat, but it was far from ordinary. Its skin had turned a vivid red, covered in numerous patterns that swirled around its red skin looking hideous.

Kiyko's mind was a blank slate, consumed entirely by rage, lost in a rage and anger.

The next moment, she found herself standing over the man who had thrown her out of the house. His heart was torn out by her sharp teeth, his body drenched in his own blood. The look of horror frozen in his lifeless eyes reflected Kiyko's now monstrous figure.

For a brief moment, Kiyko felt a twisted sense of satisfaction as she gazed at her handiwork. She then turned toward the little girl, a glimmer of hope in her eyes.

But as soon as the girl saw Kiyko, she screamed, "Monster!" and ran away, shoving the cat aside in terror.

"Am I a monster?" Kiyko muttered to herself, looking down at her bloodied paws. The glimmer in her eyes faded, replaced by a deep emptiness.

The next moment, Kiyko watched from almost a third person's perspective as countless beings, both human and otherwise, were mercilessly slaughtered by her claws.

Each kill seemed to draw in more of the mutation energy that permeated the air, fueling her to become stronger.

The more she killed, the more her power grew, but with each life she took, a part of her slipped further away from what she once was.

Amidst the carnage, Kiyko's mind was clouded with rage and confusion, no longer able to grasp the passage of time or the meaning of her actions.

The image of the little girl who once clung to her with love and fear slowly faded into the fragmented memory. She didn't know what had become of the girl, nor could she remember if she had even cared.

All that remained was the endless cycle of killing, growing, and losing herself in the blood-soaked haze that now defined her existence.

Until, gradually, a semblance of consciousness returned to her, a faint flicker of awareness arose again the stronger she grew. But her rage never went away…

That was until Ray appeared and ended her tortured existence, smashing her to death and silencing the rage that had consumed her for so long.