Reincarnated as The Greatest Scientist in Another World

The muddy ground was cold against Ain's knees as he helped Nasuha home that night. The shadows of the slum swallowed them whole—broken huts leaning into each other for warmth, propping up secrets no god cared to hear.

At the doorway of a frail shack, a woman stumbled out, her face etched by years of hunger and grief. The moment she saw her daughter, she froze—eyes wide, breath caught—before a cry broke the brittle silence.

"Nasuha! Suha—my child!"

She dragged Nasuha into her arms, clinging to her like something that might vanish with the wind. Ain stood at the threshold, fists clenched so tight his knuckles popped. He wanted to cover his ears. But he couldn't look away.

Nasuha's voice cracked between her mother's frantic questions.

"They... they took me inside, Mother. They shut my mouth. They—"

Her words dissolved into sobs. Her body went limp in her mother's lap like torn cloth. The old woman rocked her gently, whispering prayers that died against the rotting walls.

Ain stepped back. The sound of it all twisted something inside him. He could still see the glint in the soldiers' eyes. He could still feel the mud when they dragged her away—while he did nothing. And that failure scorched deeper than any wound.

Outside, the night swallowed his rage. A thin mist carried the scent of charred wood and old tears. In the distance, dogs barked at the barricade wall—a wall that split light from darkness, magic from Null, the living from the forgotten.

---

Later that night, Ain sat alone on the dirt floor of his shack. A stale piece of bread lay untouched on a cracked wooden plate. He hugged his knees to his chest, back pressed against bamboo walls worn thin by rain.

This has to end.

His whisper bled into the hiss of the cold wind. His eyes flicked to a pile of scrap in the corner—broken tools, rusted nails, splintered wood. Buried beneath it, an old leather-bound notebook.

He crawled over. The spine was brittle, pages swollen from years of damp air. He blew off the dust, coughed, and cracked it open.

Scrawled on the first page was a name—his name. But not his. The true Ain. The boy this body once belonged to, before Rian Rahman's last breath stitched their fates together.

For the Null. For freedom. I must find the answer.

Ain's breath caught. He flipped through the pages with trembling fingers—diagrams in crude ink, half-formed thoughts, scraps of science that tugged at a corner of his old mind.

Magic is breath. The air feeds the lungs. The lungs make current—electricity in the blood. The brain shapes it into force. They call it mana.

He could see it—synapses sparking, bioelectric currents threading through nerves. In his old life, this would be a lecture in a sterile lab. Here, it was taboo—black magic draped in superstition.

The Null cannot make this 'breath current.' Our lungs are dead to it. They say we're broken. Born to sweep floors, scrub feet, die nameless.

Ain's fingers dug into the paper. He turned to a page sketched with crude city lights and power conduits—what passed for them here.

All lights, all heat—filled daily by handlers. Their mana fuels every stone lamp, every gate.

He shut his eyes. Magic—sihir—was only raw power. Bioelectricity by another name. If he couldn't draw it with lungs, he would forge lungs of iron and fire. If they breathed mana, he would build steel to breathe for him.

On the last page, the boy Ain's final plea:

If I die, whoever finds this... continue. The Null must have their own power. If our lungs are dead, build new ones from metal.

Ain pressed the notebook to his forehead. A spark flared in his chest—steam pipes, spinning turbines, wires that hummed like thunder. Light no mage could tax. Fire no noble could snuff out.

---

By dawn, the mist clung to the alleys like a dying ghost. Ain stood at the slum's edge, feet half-buried in mud, staring where broken huts bled into the dark tangle of woods.

Beyond those trees waited monsters—beasts with fangs tougher than dull blades, vines that moved like snakes in the dark. The forest was a graveyard for Null who strayed too far. But to Ain, it was fuel.

If I am to build iron lungs, I need a heart to feed them.

He pictured it: scraps of metal, driftwood, broken turbines pieced into a crude generator. But for that, he needed more than rotting huts—he needed the forest's secrets.

He turned back. The village lay curled in its misery like a dying dog. Somewhere, Nasuha slept in her mother's arms. Somewhere, mothers prayed their daughters wouldn't be next.

This ends here, he promised the darkness.

---

He scavenged the next day—broken knives, bent nails, lengths of old rope. He carved branches into stakes, sharpened stones into crude blades. He tested their heft in his palm—primitive, but better than bare hands.

In the corner, the notebook lay open under a sputtering flame. He copied diagrams onto scraps of cloth, redrawing pipes, levers, the rough blueprint of a steam core.

In the back room, his mother's cough cracked the silence. From the next hut, he could hear Nasuha's restless sleep—nightmares that whispered his name like a rusted chain.

Ain pressed his palm to the cold dirt. I will give you warmth. I will give you light. And I will build a world where no one rips that light away.

---

When dawn broke again, the sky was a split wound. He strapped a ragged bag over his shoulder—bread crusts, his makeshift blades, and the notebook that held a dead boy's dream.

At the edge of the village, the forest loomed—Bukit Taring, the Tooth Ridge. They said its shadows were alive, its soil fed on bones. But Ain did not flinch.

He turned once. Behind him, the Null village crouched in its filth. Smoke curled from broken chimneys. Somewhere, mothers braided their daughters' hair and begged them to keep their heads down.

Ain faced the trees. He whispered to the wind:

I will build steel lungs. I will strike the match that turns this mud to fire.

Step by step, he crossed the threshold—into the belly of monsters, carrying only firelight and the promise of revolution in his hands.