When a God of Destruction Was Reincarnated in Tensura:

For the past few days, Rimuru had been enjoying a rare period of peace in Tempest. With Shizu finally revived, life seemed brighter, and Rimuru spent most of his time either with her or casually strolling around the streets of the bustling city. However, Raphael, as always, never let him relax completely.

: [Master, Milim Nava is approaching Tempest at an incredible speed.]

Rimuru stopped mid-step, sighing deeply. "Milim? Let me guess, she's coming for that fight I promised her, isn't she?"

: [That is highly probable, Master.]

Rimuru pinched the bridge of his nose, a mix of amusement and annoyance crossing his face. "Of course she is. I shouldn't have opened my big mouth. Alright, I'll deal with it."

He teleported to a hill overlooking Tempest, standing with his arms crossed as he waited. It didn't take long for Milim to notice his presence. She adjusted her flight path and zoomed straight toward him at breakneck speed, landing with a dramatic flourish.

"Rimuru!" Milim called out, her voice full of excitement as she grinned from ear to ear. "You didn't forget our promise, right?"

Rimuru chuckled, shaking his head. "How could I? You've been waiting for this since the last time we met."

Milim put her hands on her hips, puffing out her chest. "Good! Because I'm not leaving until we have our fight today."

Rimuru scratched his head. "Alright, alright. But we're not doing it out here. Let's head to the Labyrinth. Some of the floors are ready, and it's the safest place for us to go all out without leveling half the city."

Milim's eyes sparkled with excitement. "Ooooh, the Labyrinth! I've been wanting to see it. Let's go!"

Rimuru summoned Diablo, Zegion, and Veldora, all of whom arrived promptly. The moment Veldora appeared, he was already grinning ear to ear. "A fight, you say? Between Rimuru and Milim? This will be legendary! I must witness it!"

"Veldora," Rimuru said dryly, "you're not here to watch—you're here to help. We need to set up a barrier that can withstand the kind of destruction Milim and I might cause."

Zegion bowed deeply. "Understood, my lord. I shall ensure the barrier is impenetrable."

Diablo, always eager to serve, smiled wickedly. "As you command, Rimuru-sama. I will ensure that no outside interference disrupts your glorious battle."

With their combined efforts, they created an incredibly powerful barrier within the Labyrinth's 50th floor, an expansive, desolate battlefield designed specifically for testing overwhelming power. The area was surrounded by cliffs and molten rivers, with an artificial sky glowing faintly above. The barrier was reinforced with layers of magic from all three of Rimuru's companions, ensuring that even Milim's most destructive attacks wouldn't cause damage beyond its confines.

Milim stood at the center of the arena, bouncing on her toes like a fighter warming up. "This place is amazing! Rimuru, you've really outdone yourself."

Ramiris:" Hey.. not fair I built the Labyrinth!!".

They decided to ignore her....

Rimuru then smirked, stepping into the battlefield. "Glad you like it. But remember, we're keeping this friendly. No annihilating me, okay?"

Milim grinned mischievously. "No promises!"

"Alright, Rimuru," Milim said, cracking her knuckles. "No weapons at first. Let's see if you can handle me in a proper brawl before we bring out the big guns!"

Rimuru sighed, stretching his arms. "Fine, fine. But don't come crying to me if you get hurt." Despite his words, his eyes sparkled with excitement. This was the kind of challenge he'd been waiting for.

Rimuru activated Omni Evolution, his body adapting to match Milim's strength. The two locked eyes for a brief moment before Milim launched forward at blinding speed.

Her fist came hurtling toward Rimuru's face like a meteor. He barely dodged, leaning back and countering with a spinning kick aimed at her ribs. Milim blocked it with her forearm, the impact sending shockwaves through the ground.

"You've gotten faster!" she exclaimed, grinning as she unleashed a rapid combination of punches and kicks. Rimuru countered each strike with precision, his Heavenly Spiral Palm technique deflecting her blows while sending small bursts of energy back at her.

Milim leapt into the air, flipping mid-spin, and came crashing down with a devastating axe kick. Rimuru dodged just in time, the ground where he stood shattering into a crater. He countered by teleporting behind her with Void Step, landing a clean palm strike infused with magicules directly onto her back.

Milim stumbled forward but recovered instantly, turning with a feral grin. "Not bad, but you'll need more than that!"

She activated Dragon Fist, her hands glowing with fiery energy, and launched a powerful punch. Rimuru caught it, their clash creating a massive shockwave that flattened the nearby terrain. Before he could retaliate, Milim spun, using the momentum to deliver a high kick that sent him skidding back.

The ground cracked beneath their feet as both combatants drew their weapons. Milim unsheathed Asura, her god-grade sword, the blade gleaming with an aura of destruction. Rimuru summoned his MoonLight Edge, a masterpiece infused with his own magicules, its blade glowing faintly with power.

"Show me what you've got, Rimuru!" Milim shouted, charging forward.

Their swords clashed with a deafening roar, sparks flying as their weapons met. Milim's strikes were fast and relentless, her Battle Will Art pushing her swordsmanship to its peak. Rimuru countered with Thousand Blades Moon Style, his blade moving in intricate, unpredictable patterns that created afterimages to confuse his opponent.

Milim grinned, her Milim Eye analyzing his technique in real time. She adjusted her movements, parrying his attacks with uncanny precision. Their swords blurred as they exchanged strikes, each one testing the other's limits.

Rimuru feinted left, then spun to the right, aiming a horizontal slash at Milim's midsection. She blocked it with ease, retaliating with a downward slash that Rimuru barely avoided. He used Void Step to teleport above her, coming down with an overhead strike. Milim raised her sword just in time, the clash creating a shockwave that sent both of them flying back.

"Not bad, not bad!" Milim laughed, flipping in mid-air to land gracefully. "But I'm just getting started!"

She activated Multiple Barrier, surrounding herself with layers of protective energy. Rimuru responded by channeling magic into his katana, executing an evolved Melt Slash that cut through her barriers like butter. Milim's eyes widened in surprise, but she quickly recovered, launching a counterattack with a devastating horizontal slash.

Realizing they were evenly matched with swords, the two shifted tactics. The air around Milim shimmered as her Magicule Breeder Reactor activated. Milim flew into the air, raising her hand to summon her signature magic attack, Dragon Nova.

Rimuru feeling the sudden increase in Milim power asked Raphael.

Raphael:" Master, Milim sudden power increase is due to her activating her Magicule Breeder Reactor."

Rimuru then told her to copy it.

The massive sphere of energy grew larger by the second, crackling with destructive power.

"Let's see how you handle this, Rimuru!"

Rimuru smirked, activating Beelzebuth. The black mass of his skill surged forward, swallowing Dragon Nova whole before it could explode. "Nice try, but you'll have to do better than that."

He retaliated with Black Star Implosion, a new spell he'd developed. A miniature black hole formed in his palm, crackling with concentrated energy, before he hurled it toward Milim. She dodged just in time, the spell exploding behind her and tearing a massive chunk out of the landscape.

Milim countered with Dragon Buster, a concentrated beam of energy aimed directly at Rimuru. He activated Omni Evolution again, adapting to the sheer heat and pressure of the attack as he dodged and redirected the beam with his katana.

"Impressive!" Milim shouted, her eyes sparkling with excitement. "But let's see how you handle this!"

Activating Satanael's Judgment, Milim unleashed a massive wave of wrath-infused energy. Rimuru responded by summoning his own ultimate technique, Infinite Edge Storm, a whirlwind of sword slashes and magic blasts that collided with her attack. The resulting explosion shook the entire Labyrinth, forcing Veldora, Diablo, Zegion, and Ramiris to reinforce the barrier around the battlefield.

:" Master the Magicule Breeder Reactor copy has been successful, would you like to activate it?"

Rimuru: " it's about time and yes!!!"

The influx of unlimited magicules bolstered his power, bringing him back to full strength.

Milim's jaw dropped. " You... you got Stronger!."

Rimuru replied with a smirk.

With their powers evenly matched, the two launched into their final clash. Rimuru used his Void Step to appear behind Milim, launching a rapid combination of strikes from his katana. Milim countered with Dragon Fist, her glowing punches colliding with his sword strikes in a dazzling display of power.

Finally, Milim leapt into the air, gathering all her remaining energy into a massive attack. "This is it, Rimuru! My strongest attack—Wrathful Dragon Cataclysm!"

Rimuru didn't hesitate. Channeling all his magicules into his katana, he unleashed Eternal Severance, a blade of pure energy that cut through dimensions. The two attacks collided, creating an explosion so massive it could be felt all the way in Tempest.

The Aftermath

When the dust settled, both Rimuru and Milim were standing, battered but smiling. "That... was awesome!" Milim shouted, throwing her arms in the air. "You're the best sparring partner ever, Rimuru!"

Rimuru chuckled, sheathing his katana. "You're not so bad yourself. But next time, I'm coming out on top for sure."

The two walked back to their friends, who had been watching the battle in stunned silence.

"That was insane!" Veldora exclaimed. "You two nearly destroyed the Labyrinth!"

Ramiris pouted. "You're lucky we reinforced the barrier, or the whole Labyrinth would be gone!"

Aftermath: Celebrating the Fight

Back in Tempest, the group gathered for a feast. Milim ate enough for ten people, her energy completely restored. Veldora regaled everyone with his dramatic play-by-play of the fight, while Ramiris complained about how close they came to destroying the Labyrinth.

"Milim," Rimuru said, raising a glass, "you're crazy strong, but next time, don't hold back so much."

Milim laughed. "I didn't hold back! You're just a better fighter than before. But next time, I'll win for sure!"

As the night went on, the group celebrated the bond between Rimuru and Milim, their rivalry stronger than ever. And though the Labyrinth needed repairs, the fight had been worth every moment.