The first clash shattered space itself.
Rimuru moved like water as his fist met Keith's palm with the sound of cracking thunder, and the shockwave rippled outward in concentric rings of distorted space. They separated, circled, and collided again.
And again.
And again.
Keith's Ancient Magic spells were launched in complex patterns and complicated sequences. Each spell was executed with unbelievable mastery that can only come from eons of practice.
Rimuru countered each one, though. A wave of his hand redirected Keith's gravitational forces. A step to the side placed him outside the tear in space. His own defenses neutralized everything else.
They seemed even. Perfectly, impossibly even.
But...
Keith grinned as he unleashed a barrage of elemental attacks. But they all just dissipated as soon as they came into contact with the shimmering barrier that covered Rimuru's skin like a film.
"Not bad!" Keith called out, genuine excitement in his voice. "As I thought, you really are—!"
Rimuru didn't respond. He just moved.
A punch. Keith blocked. A kick. Keith dodged. A wave of destructive aura blast. Keith countered with his own. The exchange accelerated, becoming a blur of speed and power that would have been invisible to mortal eyes.
But Keith felt that something was wrong, and he couldn't quite put his finger on it at first. The fight felt right—the power levels matched, the techniques countered each other perfectly, the thrill was there. But there was something in the way Rimuru moved.
Like—
—like he was holding back.
No.
Not like.
He was holding back.
"You're not trying," Keith said, his smile fading slightly. "Are you trying to insult me?"
Rimuru's golden eyes met his. "No. Not really. Does that make you lonely?"
It should have been infuriating, but Keith only felt more excited. If this wasn't Rimuru's full power, then what would it look like when he stopped playing?
"Then let me give you a reason to try," Keith said, and his aura exploded.
The Ancient Magic spells Keith had been using before was nothing compared to what came next.
Concept Magic. Life and Death and everything between.
The clashes intensified. Keith's attacks came faster, harder, more desperate. And yet Rimuru took it all.
Every hit connected and every spell landed. Keith's fists hammered into Rimuru's face, his chest, his body, each impact releasing enough energy to vaporize the planet's surface. Rimuru was sent flying, crashing through the boundaries of the Sanctuary.
But things still felt wrong.
Keith could feel it. The impacts were solid, the damage was real, but there was no resistance. It was like hitting a sandbag that had been specifically placed there to be hit. Rimuru wasn't defending. He was just... letting it happen.
"Fight back!" Keith roared, his excitement turning to frustration. "FIGHT BACK!"
Rimuru picked himself up from where he'd been sent crashing. His clothes were torn, his face was deformed, his body showed signs of devastating trauma.
Then, as Keith watched, all the damage simply... reverted.
In seconds, Rimuru stood there looking exactly as he had at the start of the fight—unbothered and utterly undamaged.
"Are you done?" Rimuru asked, his tone so flat and bored it could have been used to plane wood. "Sorry, I was trying to make you think you were gonna win, but it's painfully clear that I failed. Better luck next time, eh?"
The words weren't aggressive. They weren't even particularly mean. They were just... dismissive. Like Keith was nothing more than an inconvenience. And that, somehow, was worse than any insult Keith had ever received in his life, and so he felt something he hadn't felt in millennia—anger. Real, genuine anger that replaced his usual amusement and sadism.
"You—" he said, his power spiking wildly.
But Rimuru wasn't paying attention anymore. He reached out into empty air, his fingers closing around something that wasn't there. Then he pulled, and spacetime cracked.
"Spatium."
A black line appeared in the white void of their battlefield. It was a line of absence. The complete lack of everything. And from that absence, Rimuru drew out a blade—a long and elegant blade, but unsettling in all manner of ways. It wasn't black like any material substance. It was black like the void between atoms, like the emptiness at the center of collapsed stars.
"Uriel's the best."
The blade had no weight because it had no mass. It was carved from pure spatial nothingness, an edge so fine it existed in dimensions between dimensions. It didn't just cut through matter—it severed the concept of material existence wherever it passed.
Rimuru held it loosely, a little carelessly, eve, and the weapon looked delicate in his soft and feminine hands. His amber eyes caught what little light existed in their battlefield, shining with an intensity that was almost hypnotic.
And Keith felt something churn inside him.
......
...
...
Keith had never truly cared about winning or losing. In his long existence, such concepts were meaningless. He lived for the thrill of the fight, the joy of going all-out against an opponent who could actually challenge him. Even if he thought he might not win against Rimuru, the prospect of fighting at full power was exhilarating.
That's what he told himself, anyway.
But looking at the boy in front of him—delicate, slim, holding that impossible blade of black with those ridiculous shining amber eyes—Keith felt something he couldn't quite name.
His fingers were shaking.
Just slightly, but they were shaking.
Keith was a psychopath. He had a clinical numbness to fear, an inability to process terror the way normal beings did. His mind literally couldn't register the emotion properly. But emotions weren't just mental—they were physical too. And his body, operating on instincts, was trying to tell him something his mind couldn't process.
It told him of danger, of threat—of death.
The shaking intensified slightly. Keith stared at his own hand like it belonged to someone else, confused by the betrayal of his own body. He wasn't afraid. He couldn't be afraid. The emotion simply didn't exist in his psychological makeup.
So why were his hands trembling?
"Are we doing this or not?" Rimuru's voice cut through his thoughts. "Because I really do have places to be."
Keith looked up, meeting those amber eyes, and felt the trembling spread to his arms. His mind remained clear—no fear, no panic, just analytical observation of his own unusual reaction. But his body knew of the terror his psyche refused to acknowledge.
"Yeah," Keith said, his voice steady even as his hands shook. "Let's do this."
And then they clashed for one last time.
Keith poured everything into his final attack. It was everything he had, everything he was, compressed into one moment of absolute annihilation.
Rimuru simply swung his blade. The void sword moved through space like a brush through wet paint.
The two attacks met in the center of their battlefield.
Light—pure, blinding, all-consuming light—exploded outward. Not the light of stars or supernovas, but the light coming from a source that couldn't be scientifically defined. The entire Sanctuary they'd been fighting in couldn't contain it. The walls of their dimension cracked, shattered, and disintegrated.
When the light faded, only Rimuru remained standing.
"You know," Rimuru said quietly, speaking to the empty air—or perhaps to Keith's fading consciousness, "strength was never really my forte. Neither was fighting."
He looked down at his hands, still holding the void blade. The weapon was already dissipating, returning to the nothing it had come from.
"I felt lost once. So unbearably lost that I thought rage would consume me if I kept going down that path." His voice was soft, a little vulnerable. "But then I found anchors. Small things that mattered. Daisy—just a cat I saved. And Iu. They didn't seem special, except they were. But they mattered to me more than anything."
Behind him, Keith's body was crumpled and dissolving, finally succumbing to the severance of his existence.
"And you took them from me," Rimuru continued. "That's where you lost. Because you made it personal."
He turned to face Keith's remains. "I was going to stick to what I said. Going to let you experience the true meaning of pain myself. But honestly?" He sighed. "I'm beginning to think that you're not even worth the effort anymore. So, this is farewell, God of Mischeif."
"Beelzebuth."
A raging black vortex erupted from Rimuru's extended hand. It devoured Keith's dissolving body completely, consuming everything all the way down to his ego.
"Raphael can handle the torment part," Rimuru muttered. "She's better with that than I am anyway."
The alternate space began creaking now that Keith's power was gone. Cracks spread across the white void like a shattered mirror. Rimuru prepared to leave, ready to return to Tortus, check on his friends, and annihilate the rest of the enemies.
But then...
"Yue?"
He saw Yue lying on the ground perhaps twenty feet away, unconscious and back in her normal young form. Her blonde hair was spread around her, and her breathing was shallow but steady.
"Where did he—"
Confusion seeped through Rimuru's tired mind. Where's Ehit? I don't sense anything foreign in her body. Did Keith somehow...
He walked over and reached down for Yue's body, ready to scoop her up and take her home to Hajime.
But then—
BANG
—the fist that hit him was so large, so impossibly powerful, that Rimuru didn't even register it as an attack at first. It connected with his face with force that transcended physical impact.
The entire Sanctuary—the "Heaven" of the false gods—collapsed in a single instant. The alternate space shattered like glass. And Rimuru, still holding Yue, was launched backward with apocalyptic momentum.
He shot through dimensions, through the closing gate, through the sky itself, and slammed into the surface of Tortus with an explosion that could be seen from orbit.
···—–—⚜—–—···
The fighting hadn't stopped on the surface, but then it did.
The battlefield—where thousands of Apostles were still engaged with the mortal forces—erupted in chaos as the shockwave hit. Rimuru's explosive re-entry brought everything to a halt. The crater he created was massive, smoke and debris fountaining upward in a mushroom cloud, and it smoked and crackled with reddish lightning. Soldiers and heroes alike turned to stare, weapons half-raised, unsure whether this was another enemy or—
Rimuru stood up.
He looked visibly distraught for the first time since anyone had known him. His usual calm was gone, replaced by genuine confusion and surprise. In his arms, held protectively against his chest, was Yue. She was unconscious but protected by his power from the impact.
"Rimuru!" Hajime's voice shattered the silence. He and Tio were already running toward the crater.
The sky darkened.
No—not darkened. Something was blocking the light.
Something fell from the closing gate above—fell like a meteor, like judgment itself, like the end of all things. It crashed into the battlefield with force akin to Rimuru's.
When the dust cleared, it revealed a towering man—somewhere between thirteen and sixteen feet tall, with pale white skin and flowing green hair. It was like a giant from ancient myths.
"Now who the hell is that?" Rimuru asked.
Hajime reached the crater's edge, and Rimuru immediately tossed Yue to him. The white-haired young man caught her reflexively, his demon eye immediately scanning her for injuries.
"Is she—"
"She's fine," Rimuru said shortly. "Just unconscious. Get her somewhere safe."
Tio landed beside them, her draconic form dissipating as she took in the towering figure in human form. "What is that thing?"
"Don't know yet," Rimuru said quietly, massaging the back of his head. "But it sure hits hard."
"Mine paramour... that entity. Its power is..."
"Yeah," Rimuru agreed. "I know."
The giant stretched, cracking its neck with sounds like breaking stone. Then it looked around with an expression of... disappointment?
"Ugh. I know I was open to contracts, but seriously? A lowly world like this?" It sighed dramatically. "The degradation. The absolute disrespect. Do you know how long I've been sealed? How boring eternity is? And this is what I get summoned to? A backwater planet with barely any—"
It stopped mid-complaint, its eyes locking onto Rimuru.
The annoyance melted away, replaced by something like fascination. A smile spread across its massive but handsome face—neither cruel nor mocking, but genuinely intrigued.
"Ohhhh," it said softly. "Ohhhh~, you're interesting!" It took a step forward, and the ground cracked beneath. "You... you're not of this world, are you, demon lord?"
Rimuru tensed. His senses had been scrambling to analyze the entity, but the information coming back was... concerning. Extremely concerning. This wasn't like Keith. This was something operating on a completely different scale.
With nothing to say, Rimuru defaulted to sarcasm. "Wow. You're big."
The giant laughed—a booming sound that echoed far and wide. "Oh, I like you already, brat! Direct. Rude. Completely unbothered by me." It placed a massive hand on its chest. "I am Fenn. Pleased to make your acquaintance before I crush you into paste."
"Hmm. Okay," Rimuru muttered. "So what, Ehit summoned you? Where is he, by the way?"
"Ehit?" Fenn's smile widened. "Oh, the little thing? He's dead. Very dead. Hilariously dead, actually." He examined his fingernails. "See, he pulled off a forbidden ritual. Learned it from that fellow you were fighting, I assume. A grand summoning to call forth a truly mighty and divine being to serve him."
Fenn's grin turned predatory.
"What he didn't know—what none of them ever know—is that such summonings come at a price. The summoner's soul, completely eaten to fuel the ritual. The moment I arrived, he just... pop." Fenn made an exploding gesture with his hands.
Rimuru's mind raced. He couldn't have pulled it off on his own... did he resort to taking that other god Ghidorah's sleeping body. That must have been part of the ritual components.
"Now, before we get to the fun part," Fenn continued, rolling his massive shoulders, "I should mention—this isn't even my real body. When conducting contracts like this, I can never manifest at full power. There's always limitations—all very annoying." He smiled again. "But you know what? It's enough. Enough to scratch that itch, you see. Enough to indulge in a little violence."
He paused, his smile becoming something more ominous.
"You see," Fenn pointed upward. Not just at the collapsing gate, but at the boundless sky beyond, "I am sealed by God. Capital G. The real deal. And after countless eons of boredom—and I mean eons, you can't imagine how tedious eternity gets—I made a deal with the leader of the Original Angels. Let me perform contracts, like those pesky demons do. Let me have a little fun from time to time, and I won't try to break my seal."
His finger lowered to point directly at Rimuru.
"And so here we are! It's a pity that your monster play ends so soon, but there's nothing we can do about that."
The other fighters—heroes, soldiers, even the remaining Apostles—were backing away. The sheer pressure emanating from Fenn was suffocating, primal, absolutely terrifying on a fundamental level.
Rimuru laughed. "Are you serious? Another one of y'all? Gods with questionable backstories but delusions of grandeur?" He shook his head. "I just dealt with one of you. It ended horribly for him."
But internally, his assessment was far less cavalier.
This could be bad. He's not bluffing about being sealed—I can sense the restrictions on him, the limiters holding him back. But even restricted, even with a time limit, he's...
The power of this giant was immense. Far greater than Keith. Far greater than anything Rimuru had faced in this world. And the worst part? Fenn seemed genuinely excited. Not overconfident or delusional—just... eager. Like a child about to play with a new toy.
Screw it, Rimuru thought, his expression hardening with determination. I'll win no matter what. I have to.
"Hajime," he said without turning around. "Get everyone as far from here as possible."
"Rimuru—"
"Now."
Something in his tone made Hajime move without further argument. He scooped up Yue and signaled to the others. The retreat began, organized chaos as humans and heroes alike scrambled to distance themselves from the impending clash.
Fenn watched them go with amusement. "Not going to argue for your friends to help? No power of friendship?"
"They'd just die," Rimuru said flatly. "So what's the point?."
"You're right. It'd be pointless." Fenn's power began to manifest—not all at once but gradually, like a dam slowly opening. "I appreciate the honesty. Most try to be heroic right up until I rip their spines out."
"I'm not like most, though."
"No," Fenn agreed, his smile widening into something genuinely dangerous. "No, you're really not."
They stood facing each other—the towering ancient giant and the demon lord.
"So," Fenn said, cracking his knuckles. "Shall we dance, little demon lord?"
Rimuru's power surged in response, golden light mixing with deeper, darker forces.
"Sure. As long as you wish, too. You'll never be able to stop this monster play, anyway."
The world held its breath.
A Giant from ancient myths, against an anomalous Demon Lord. Surrounding them were thousands of Apostles, but to these two, they seemed no more than mosquitos that can be squashed at any time.