The ground beneath Kai's feet still trembled, pulsing at a frequency that seemed intent on shattering everything inside and out.
Zak was lying beside him, gasping, his arm covered in dark blood, eyes wide with pain and disbelief. All around, the distorted landscape of the Nexus vibrated, dissolving into shards of glass, flesh, and shadow, each breath carrying that metallic taste that clung to the tongue.
For a moment, Kai felt the core take over his entire body, heat rising to his ears until he lost track of where he began and ended.
Zero was there, a cold and constant presence, assuming control of his movements. The world dissolved into confusing noises: monster screams, crackling energy, words he didn't understand, overlapping voices.
Kai blinked hard, trying to regain control, but it felt like he was floating in a current where any memory could be swept away at any moment.
It was as if his very skin no longer belonged to him. Every piece of his body felt delayed in relation to his thoughts.
In a flash, he realized he was standing, his hands soaked in a viscous substance that wasn't human blood. Three creatures lay around him, their twisted bodies dissolving into the pulsating ground, empty black eyes staring into nothing.
Zak, dazed, tried to get up, leaning against a pillar that looked more like it was made of bones and electric wires.
"Did you… you do all this?"
His voice was hoarse, more frightened than grateful.
Kai felt the answer on the tip of his tongue, but the sound that came out was strange, stuttered.
"I… I don't remember. I just…"
He stopped, feeling dizzy.
The images came in flashes: shadowy tentacles, a sea of eyes, buildings collapsing in slow motion, voices singing an alien, senseless song. Memories that weren't his crossed his mind, one after another, civilizations collapsing under a purple sky, temples consumed by metal creatures, black-eyed children running through dark streets.
And among these fragments, words in languages he'd never heard echoed loudly, as if trying to stick to the surface of his brain.
Zak coughed, wiping his mouth with the back of his hand.
"Kai, look at me. Are you listening?"
His face was a mask of worry and fear.
"Something's wrong. This isn't just… power. You're different, you hear?"
Kai shook his head slowly, trying to anchor himself in reality, but it felt like everything around him was made of water, one wrong move and he'd sink for good.
Zero spoke, his cold voice cutting through the confusion.
"Personality fragmentation stabilized. Hostiles neutralized. Immediate risk reduced."
Behind the voice, Kai felt something else: a kind of satisfaction, as if Zero were testing his own limits, manipulating Kai's body with clinical precision.
Kai knelt beside Zak, pulling a strip from his friend's torn coat to try to stem the blood still flowing from the wound. The touch on his own fingers felt distant, almost like it belonged to someone else.
"Hang in there. I don't know if I can do much, but… we need to get out of here."
Zak chuckled humorlessly, sweat shining on his forehead.
"The way you are, I should be the one helping you. Kai, what the hell happened to you? Seriously. Don't pretend it was just adrenaline."
Kai wanted to answer, but the words stuck. Part of him wanted to tell everything: about Zero, about the voices, about the emptiness growing inside with every creature defeated. But another part, maybe the one Zero controlled, just wanted to pretend none of it was real, that it was all just another Nexus nightmare, the kind that ends when you wake up.
Deep down, he knew nothing would end easily.
The way back was a very strange maze. Walls that changed places, shadows that whispered secrets, cracks in the floor that seemed to breathe. With every step, memory fragments insisted on appearing, each one stranger than the last: battlefields with no humans, only beings of light fighting darkness, machines buried in the hearts of dead planets, spiral towers with doors sealed by moving symbols.
Kai stopped, panting, leaning against a wall that dissolved into mist before his eyes.
"Zero… what is this? Why am I seeing these things?"
Zero took a while to answer, as if processing millions of pieces of information at once.
"Partial fusion resulted in residual data sharing. Fragments of civilizations absorbed during combat. Memories not belonging to the host. Emotional stabilization recommended."
The tone didn't help. It was dry, as if all of it was just another unimportant experiment.
Zak kept limping beside Kai, quieter than before, watching from a distance but not daring to ask questions.
The silence between them grew heavy, only broken by the sound of their own footsteps and irregular breathing.
When they finally found the exit of the Nexus, the portal looked smaller than before, as if it had consumed some of its own light.
Zak leaned against the arch, wiping blood from his arm, eyes still glued to Kai.
"Are you really okay? I swear, if you say 'I'm fine,' I'll punch you—even with no strength in my arm."
Kai opened his mouth to speak, but what came out was a short, almost desperate laugh.
"I don't know what I am now, Zak. Honestly. There are things in my head that… aren't mine. I remember things I've never lived. I see cities that don't exist here. I feel homesick for places I don't know."
Zak's gaze softened for a moment but quickly hardened again.
"I don't know, Ender. Just don't turn into one of those monsters. I've seen too many good people get lost in these Nexuses."
Outside, the city light seemed aggressive, filtered through thick, dirty clouds. The smell of smoke and ozone still clung to the skin. The feeling of being out of place was worse now—every sound seemed delayed, every color faded, as if the real world was just a shadow of what was left behind.
Zak wiped his dirty face, breathing deeply.
"We need to go home. You especially. You're as pale as a ghost."
On the way back, Kai tried not to look at people, at the low-flying drones, at the red lights blinking on the poles. The whole time, his eyes burned, the core vibrated intensely. Every shadow seemed to try to drag him inside, as if the Nexus wanted one last piece.
They arrived at the neighborhood almost without exchanging words. Zak glanced sideways before disappearing around the corner.
"If anyone asks, say I saved your skin. Good for my résumé."
Kai managed a smile, but stood still, watching Zak disappear, his hand still feeling his friend's dried blood.
Kai entered the warehouse slowly, each step heavier than the last, his whole body aching with exhaustion and his thoughts in a jumble. The smell of rust and mold, mixed with the rain trickling through the cracks, was anything but welcoming.
The light was dim, just enough to see the shine of a puddle near the door and, beside a pillar, Lina sitting on the floor, hugging her knees, completely curled up.
She raised her head in fright at the sound of footsteps, her face pale, eyes still red with worry. For a few seconds, she stood still, as if not really believing her brother had returned.
"Kai? Is it really you?"
Her voice came out small, distrustful, half-broken by fear.
He could only nod, too exhausted to even try to smile.
"It's me. I made it back."
His voice came out hoarse, low, almost a whisper.
Lina stood up slowly, not knowing whether to run to hug him or keep her distance. She stood in front of Kai, observing every detail, the shortness of breath, the sweaty skin, the different eyes, lit up in a strange way.
"What happened to you?" she asked, trying not to let her voice crack. "You disappeared. Everyone was talking about a new Nexus, soldiers on the street, people scared. I stayed here, waiting. You seemed like someone else when you left, and now you're… weird."
Kai took a deep breath, feeling a sharp pain growing in his head. The memories came in quick flashes, images of distorted worlds, meaningless words, voices mixed with his own, and all of it wanted to escape through his mouth, but he couldn't turn the chaos into an explanation.
"I… I can't explain, Lina. It was different from anything. It's like… like I brought pieces from in there with me. There's stuff in my head that isn't mine. I see places, scenes, memories that aren't mine."
She moved a little closer, squeezing her own arm, not knowing whether to believe or doubt him.
"You're talking like you're sick. Or crazy. I don't want to lose you, Kai, but you're scaring me. It's not just exhaustion, I know you. It's something else."
Kai closed his eyes, trying to hold back tears and the weight of everything he couldn't share.
"I wish I could explain it to you. Really. But I don't even understand it right. I just feel like there's too much in here, like part of me got stuck in there and something else came back with me."
Lina ran her hand over her face, desperation clear.
"Just promise you won't leave me alone. Even if everything gets worse. Even if you change, don't leave me, okay?"
"I promise to try," he replied, his voice almost fading. "I just need you to remind me who I am, if I start to lose myself. Don't let me forget."
She nodded, and, for the first time, stood beside him in silence, just listening to the sound of dripping water, the wind coming through a crack, and the echo of their own fear.
The hug was awkward, but real, two survivors, trying to hold on to what remained.
Kai spent the rest of the night awake, sitting on the cold floor, looking at his twisted reflection in a dark puddle. His eyes shone too much, almost inhuman, and behind them, shadows moved as if they had a will of their own.
He tried not to think, tried not to listen to the strange voices in his head, but Zero whispered silently, dictating rules and warnings that only he could hear.
"Balance is fundamental. Consume without losing yourself. Fragments must be processed or the mind dissolves." But these words would never pass Kai's lips.
He just squeezed his eyes shut, clinging to the sound of Lina's breathing, trying to believe, even if it was a lie: "I'm still me. I'm still me."
And that night, what kept Kai whole wasn't the core or the power, but Lina's presence, close enough to remind him of what really mattered.