The air over the capital city of Rimuru was no longer the air of a peaceful forest; it was a pressurized curtain of magical energy. While Kaito had already undergone his transformation, the "Harvest Festival" for Rimuru required a more specific catalyst: the souls of the invading army. Twenty thousand Falmuth soldiers had been lured into the killing fields surrounding the city, trapped beneath a specialized barrier Kaito had designed to prevent any soul from escaping into the cycle of reincarnation.
Kaito stood at the center of the ritual site, his silver hair now adorned with floating, crystalline fragments of magisteel that acted as external processors for Ultimate Skill: Mnemosyne. He looked less like a man and more like an astronomical event.
"The preparations are complete, Rimuru," Kaito said. His voice didn't just travel through the air; it resonated through the ley lines of the planet. "The Falmuth army has been neutralized. Their souls are currently being held in a 'Stasis Archive'. They are the fuel for your ascension."
Rimuru, standing atop a raised stone dais, looked out over his silent city. The citizens—the Goblins, the Orcs, the Direwolves—had all been put into a deep, magical sleep to protect them from the fallout of the evolution. "I never wanted to be a mass murderer, Kaito. But after what they did to our people... I can't let them go."
"They came to harvest us," Kaito replied, his eyes cold and distant. "We are simply returning the favor. Mnemosyne, initiate 'Soul Transfer: The Great Gluttony'."
A torrent of violet and crimson energy erupted from the horizon, swirling toward the center of the city. These were the souls of the twenty thousand—shimmering orbs of light that screamed with the echoes of their final moments. Kaito acted as the conductor, his silver hands weaving the threads of energy into a concentrated sphere above Rimuru.
[Notice: Harvest Festival for Individual 'Rimuru Tempest' beginning. Commencing Soul Integration... Success. Unique Skill: 'Great Sage' is attempting to evolve... FAILED. Attempting again... FAILED.]
Kaito frowned. "Mnemosyne, assist. Sync the sub-processors. Use the 'Record of the World' to provide the necessary blueprints for the evolution."
[Notice: Integrating 'Celestial Record' data. Evolution of 'Great Sage' into Ultimate Skill: 'Raphael, Lord of Wisdom' complete. Evolution of 'Predator' into Ultimate Skill: 'Beelzebuth, Lord of Gluttony' complete.]
The sky turned pitch black, save for the two pillars of light—one silver, one violet. The ground shook with such force that the mountains of the Jura range groaned. In that moment, the hierarchy of the world was rewritten. Two True Demon Lords were born from the same source, a phenomenon never before recorded in the history of the world.
As the light faded, Rimuru stood in his human form, but he was different. His hair was longer, his skin more translucent, and his aura was a bottomless abyss of power. Beside him, Kaito's silver form stabilized, his metallic skin now having the deep luster of polished starmetal.
"It's done," Rimuru whispered, his voice now carrying the weight of a god. "I can feel... everything. Every leaf, every soul in this forest."
"And you can feel them," Kaito added, looking toward the west. "The Western Holy Church. They're moving. Hinata Sakaguchi and her Holy Knights. They see us as the ultimate blasphemy."
[Notice: High-speed magical signatures detected. The 'Seven Luminaries' are attempting a long-range strategic strike. Initiating 'Celestial Shield: Absolute Reflection'.]
Kaito didn't even turn around. He merely raised a hand. Seven beams of blinding white light struck the invisible dome over the city, and instead of exploding, they simply reversed direction, traveling back toward their source at double the speed.
"They're panicking," Kaito said, a thin, dangerous smile appearing on his silver face. "They thought they could kill a couple of monsters. They didn't realize they were poking a hole in the heavens."
Rimuru stepped down from the dais. "We need to deal with Hinata. She thinks she's doing God's work, but she's being manipulated by the same people who sent the Falmuth army. Kaito, can your 'Mnemosyne' find the source of the manipulation?"
"I've already found him," Kaito replied. He flicked his wrist, and a holographic display appeared in the air—a record of the conversations between the Seven Luminaries and the Eastern Empire. "It's Yuuki Kagurazaka. He's been playing both sides from the shadows."
Rimuru's expression darkened. "Yuuki... another Otherworlder. One of Shizue's students."
"He's a virus in the system, Rimuru," Kaito said. "But he's not the only one. The 'Lords of the Octagram' are meeting soon. Clayman is going to try and have us purged officially at Walpurgis. He thinks he can manipulate the older Demon Lords into doing his dirty work."
Kaito walked over to Rimuru, the two of them looking out over their newly awakened people. The Hobgoblins were waking up, blinking in the new, magicule-rich atmosphere. They looked stronger, more intelligent, more divine.
"Let them come," Rimuru said, his eyes flashing with the power of Beelzebuth. "We'll go to Walpurgis. We'll expose Clayman. And we'll show the world that the Tempest name isn't a threat—it's the law."
Kaito nodded, his silver form beginning to drift into a state of semi-intangibility. "I'll prepare the Archive. If they want a war of gods, we'll give them a symphony of destruction. But first, let's go meet Hinata. I've been wanting to archive 'Holy Magic' for a while now."
The two brothers stood together—the Blue Slime of the Void and the Silver Spirit of the Record. The "Fourth Primordial" was no longer an echo. He was a creator.
[Notice: Probability of victory against the Western Holy Church: 100%. Probability of Rimuru and Kaito becoming the dominant power in the Octagram: 99.8%.]
"I like those odds," Kaito whispered.