In Another World With Omnitrix

The air inside the chamber vibrated with raw energy.

Riven's boots skidded across the fractured floor as he parried another devastating swing from the crystalline boss. The clang of Nullshift's blade against jagged obsidian armor echoed like shattered glass.

His shoulders ached. His breaths were shallow and ragged. Every second felt like a full battle on its own.

The arena shimmered with the glow of broken crystal, each fragment reflecting light from the chaos. Blood—his own—trickled down his cheek from an earlier impact.

Across the room, Lyra Veyla moved swiftly, casting frost spells with desperate precision. Each attack froze a joint, slowed a limb, delayed a strike. But the boss was adapting. Its crystalline armor shimmered, cracking in places where Riven had landed clean hits earlier—but nothing deep. It was learning from them both.

And then… it changed targets.

The creature turned its glowing cyan eyes away from Riven.

And locked onto Lyra.

She had been the one disrupting it. Slowing it, redirecting it when Riven missed.

Now it saw her as the greater threat.

Riven's voice caught in his throat. "Lyra—!"

The boss lunged.

Its massive leg swung, and before Riven could react, it slammed into him like a hammer. He flew backward, spine-first into a crystal wall.

Crack.

The impact drove the breath from his lungs. His body crumpled to the ground, ribs burning, vision swimming. He tasted blood.

Somewhere in the blur of noise, Lyra shouted something—but the words were distant.

He forced his eyes open.

Across the field, she was dodging on instinct alone. Her frost spells were fast, controlled—but her footing was failing. The boss pressed closer, each strike more violent than the last.

He blinked.

Fought to rise.

His limbs shook, but he managed to brace against the floor and push himself to one knee.

Then he heard her shout, voice tight:

"I'm not built for battle, dammit—not like this! Even as an S-rank!"

That hit something in him.

He looked up—and saw it.

When the boss twisted mid-swing, a shimmer pulsed from its chest.

Not ordinary light.

A core.

A glowing green-blue structure, buried deep behind crystal plating, rhythmic. Alien,alive.

Just like the last time.

The Omnitrix had flickered back when they'd first neared this dungeon. He hadn't understood it then. But now… now it was obvious.

This creature wasn't just powered by mana.

Its heart pulsed with alien DNA.

And the Omnitrix had recognized it.

Riven's gaze shifted to his left wrist. The gauntlet buzzed faintly—almost in resonance.

His fingers tightened around Nullshift's hilt.

The sword form was nearly out of energy. He'd used the blaster mode earlier when fighting the summoned army—and it had auto-reverted after five shots, without warning.

He hadn't known it drained that much energy. That it had a limit.

But he'd saved a little.

Maybe enough.

He stood.

Wincing through the pain, he tapped the glyph on Nullshift's side. The blade folded back, shifting with mechanical clicks and luminous energy.

Blaster mode engaged.

The barrel extended forward, glowing faintly. Flickering.

Five shots.

No more.

His vision steadied.

And he knew what he had to do.

He shouted, voice hoarse but clear, "Lyra! Freeze it—bind the arms and legs—leave the core exposed!"

She heard him.

Didn't question.

Instead, she dove to the side and launched a flurry of spells. Frost erupted from the floor, wrapping around the boss's limbs in thick chains of ice. The temperature plunged. Even the walls frosted over.

The boss thrashed violently—but its arms locked up. Its legs anchored in a tomb of frost.

And the core—still glowing, still unprotected—was wide open.

Riven ran.

He sprinted across the crystal battlefield, each step jarring through his bruised ribs. The boss roared, its chest pulsing faster as it sensed him coming.

He raised the blaster.

One.

The first shot hit the armor around the core—cracked it.

Two.

The second pierced deeper, making the boss howl.

Three.

A spray of crystal splinters burst from its chest.

Four.

The armor shattered, revealing the glowing green-blue core in full.

He didn't even notice that all his aim was direct hit and Riven was inches away now. The boss strained against the ice—but couldn't move in time.

He jumped.

Raised the blaster directly at the exposed heart.

And fired.

Five.

The final shot exploded point-blank into the core.

A burst of blinding blue-green light surged outward.

Boom.

The shockwave flung Riven backward, slamming him to the ground—but this time, he rolled with it, shielding his head.

The boss screeched.

The sound rattled the very crystal dome.

Then—silence.

Shards of glowing crystal rained down like dying stars.

The massive figure collapsed—its entire body disintegrating into shimmering dust and fractured fragments.

The boss was gone.

Riven lay on his back, staring at the ceiling.

His chest heaved with every breath. Nullshift had already reverted to sword form, dim and motionless, spent.

He blinked slowly.

Across the room, Lyra stumbled forward, ice trailing from her arms. "Riven!" she called, concern heavy in her voice.

"I'm alive," he muttered, coughing. "Barely."

She knelt beside him. "That was reckless."

"That was tactical improvisation," he corrected.

Her brow twitched. "You almost got yourself killed."

"I almost got us both out of here alive."

She almost smiled, then shook her head.

And behind them, buried beneath the shattered remains of the boss, something pulsed faintly once more.

The Omnitrix glowed—but no voice sounded. No fanfare, just a quiet flicker of light on Riven's wrist.

It absorbed the energy silently.

A new alien DNA merged into the core.

"New DNA Unlock:Petrosapien.

Code Name: Diamondhead."

Riven's eyes flicked to the device.

He felt it. A new presence. Durable. Solid. Unyielding.

He said nothing.

And Lyra noticed none of it—her eyes still fixed on his battered state.

He let his head fall back against the floor, smiling faintly.

End of chapter.

Thank you for reading.