Chapter 5 – The Dimensional Forge
The night sky above Musutafu hummed with static. Down in the park, a faint circle of light traced itself into being—blue and sharp, floating a few inches off the ground.
Sozo stood at its center, breathing slow, both palms pressed together. The Arc of Embodiment glowed along his forearms.
Deku watched, perched on a nearby bench, a mix of curiosity and nerves on his face. "You're sure this won't, uh… eat the park?"
"It'll stay contained," Sozo said quietly. "This one's small. Controlled."
The hydra's voice rumbled inside him, approving but wary.
You create not for destruction this time, but to teach. That is harder.
"I know." He extended one hand. The circle expanded, light stretching upward like liquid glass. It formed a dome, then a shimmer. The park was gone.
They stood inside nothing.
---
The space was a blank field of pale mist, no horizon, no color. Just an endless, shifting surface that reflected faintly underfoot. Every sound felt louder here. Even breathing had weight.
Deku took a cautious step. "So this is… a pocket world?"
"Minor dimension," Sozo corrected. "Created inside the Arc's field. It'll stay stable as long as I'm focused."
He gestured toward the mist. "Here, we can train without holding back."
The hydra murmured again: Form and will must coexist. Begin with the soldiers.
Sozo nodded. He drew a circle in the air with his fingertip. Threads of light poured outward, coiling together into humanoid shapes—smooth, muscular, without faces. Their skin was a pale, translucent grey, faint veins of color pulsing beneath.
Each one breathed. Not simulated—alive in the barest sense.
Deku's eyes widened. "They look… real."
"They are, until the Arc resets them. Think of them as sparring partners. They're built from raw potential."
"So, organic training dummies?"
"Exactly."
He raised his hand again, and the blank ground rippled, forming a rough terrain—ridges, dips, obstacles. The mist darkened slightly, taking on the faint hue of dawn.
"This place shifts with will," Sozo explained. "React to it. Learn from it. I'll be watching."
Deku's grin spread. "Got it."
---
The soldiers moved as soon as he did.
Three sprinted forward—fluid, animal-fast. Deku barely had time to transform before the first strike landed. Green light flashed, and Wildmutt leapt sideways, claws skidding against the slick surface.
The creature's fist smashed where he'd been, the ground splintering like glass. Wildmutt roared, launching himself at the nearest opponent. The air filled with motion—snarls, cracks, bursts of light as claws met flesh.
From outside the main circle, Sozo watched closely, eyes glowing faintly with the hydra's light. He could feel every energy signature, every distortion in the dimension. It was working—alive, reactive.
But the soldiers adapted quickly. They began coordinating—two feinting, one sweeping low. Deku stumbled under the rhythm.
"Instinct is good," Sozo called out. "But instinct alone breaks pattern! Predict!"
Wildmutt paused mid-dodge, head twitching as if sniffing the air. The next attack came from behind—he spun before it landed, catching the blow with both claws. For the first time, he countered, slamming the attacker into the ground.
Sozo smiled faintly. "There it is."
---
Time lost meaning inside the dimension. Terrain shifted without warning—flat plains folding into steep cliffs, mist thickening into fog, then clearing again. Every time Deku adapted, the world itself changed to test him.
Between waves of soldiers, he panted hard, reverting to human form for brief seconds before the next assault began.
Sozo could see his growth—not just strength, but judgment. He was learning when to act and when to wait.
He mirrors your evolution, the hydra whispered. Creation begets creation.
Sozo didn't reply. He simply willed the next set of creatures into being—sleeker, faster, their movements less predictable.
Deku growled, transforming again—claws flashing as he charged headfirst.
The battle blurred into instinct and dust.
---
Half an hour in, the strain began to show. Deku was covered in dirt and sweat, his breathing rough. The soldiers moved in perfect unison now, their flesh shimmering as if adapting to his every motion.
One landed a hit square to his chest, sending him flying back across the field. He hit the ground hard, rolling until he skidded to a stop near Sozo's feet.
"Still up?" Sozo asked quietly.
Deku coughed, forcing a grin. "Barely."
Sozo raised his hand to pause the simulation, but Deku grabbed his wrist. "No. One more round."
"Your stamina—"
"—still has some left," Deku cut in, eyes bright with defiance. "If I stop here, I'll never know what's next."
Sozo hesitated, then lowered his hand. "Then earn it."
The world shimmered, reforming into a vast arena with curved walls. The air grew heavier, gravity denser.
This time, a single soldier appeared—larger than the rest, twice Deku's size, its body plated with dark organic armor.
Deku faced it down, chest heaving, green light already flickering along his wrist.
---
The soldier attacked first, closing the gap with impossible speed. Deku tried to dodge, but the blow caught his shoulder, sending him tumbling.
He rolled to his knees, Wildmutt form flickering unstable. "Too fast…"
Sozo clenched his fists. He could feel the creature's density—it was near the upper limit of what this world could hold.
"Adapt!" he shouted. "Stop thinking like Wildmutt. Let the form change if it must!"
The hydra's voice joined his, resonating through the air: He's on the edge. Creation responds to desperation.
Deku's hand glowed brighter. The sigil pulsed once, twice.
Then his whole body was swallowed in green fire.
---
When the light faded, he was no longer Wildmutt.
A smooth, armored shell covered him from head to toe—white plates edged with black, limbs thicker, compact. His eyes glowed yellow, triangular. He crouched instinctively, then curled into a ball.
The next instant, he rolled.
Not clumsy, not uncertain—fluid and fast, a blur of motion that shattered the ground. He struck the giant soldier full-force, sending it flying into the mist wall. The impact cracked the terrain and rippled energy through the dimension.
Cannonbolt uncurled, landing in a crouch, chest heaving. The sigil on his chest flickered proudly.
Deku stared at his hands. "So this is… Cannonbolt."
Sozo's smile was quiet but wide. "Triggered by defense instinct. You created protection by becoming it."
---
The soldier rose again, staggering. Deku shifted back into rolling form, charging headlong. The collision this time sent shockwaves through the arena, scattering mist into fragments of light.
The creature dissolved into particles.
The silence that followed felt deep.
Deku reverted, collapsing onto the floor with a grin. "Think that counts as a win?"
Sozo laughed softly, stepping forward to help him up. "More than that. You unlocked what was buried in your potential."
The hydra's voice lingered in the air: Two creators now walk this world—one of matter, one of will.
Sozo looked around the slowly fading landscape. Cracks spread across the blank sky; the pocket dimension was starting to collapse from exhaustion.
"Time to go."
He snapped his fingers. The white world shattered like glass.
---
They were back in the park. The air smelled like wet grass again. Dew glistened under the streetlights.
Deku sat on the grass, leaning back, still laughing weakly. "That was insane. I didn't even think—I just moved."
"That's what instinct looks like when it listens to purpose," Sozo said. He sat beside him, looking up at the stars.
Deku grinned. "So… when's the next round?"
Sozo chuckled. "When you can breathe without falling over."
The hydra's whisper rippled softly in his mind. He will outgrow your training soon. What then?
Sozo's gaze drifted toward the city lights. "Then I'll build something bigger. A forge where both of us can be tested."
The night wind stirred, gentle and cool. The Arc on his hand glowed once, faint but sure.
And somewhere deep inside, the hydra purred like thunder.
---
End of Chapter 5 – The Dimensional Forge