"Full Resonance!" Kaito roared, a guttural sound born of fury that shattered his previous calm. The remnants of the No Life King's spell were torn away as he pushed the resonance with both Durandal and Shikabanehime far past the limits of his normal body. He became a conduit of immense power. With a flash of light and shadow, he rushed the still-reforming No Life King, who lay broken at beside him in the crater.
Kaito didn't give the King time to recover. He unleashed a furious barrage of fists; each blow a cataclysmic impact that dug the No Life King deeper into the ground. The force of his attacks caused massive tremors to vibrate across the land. Although far away, buildings in St. Petersburg shook violently, and some less earthquake-resistant structures collapsed into rubble. On the coastline, the sea waves rocked back and forth, a miniature tsunami created with each slam of his fist.
The No Life King's soul flame flickered as he taunted Kaito. "Your attempts are useless!"
Kaito ignored it all. Shikabanehime's curse latched onto the No Life King's connection to his army, and across Russia, the undead began to crumble to ash, their life force being funneled directly into Kaito's adaptation.
The King's taunts turned to wails of agony as each blow, infused with an adapted power, struck his core. Kaito was not simply breaking his bones; he was rending the No Life King's form into particles at a rate faster than he could regenerate.
...
After what seemed like an eternity, Kaito's assault slowed. He could feel the unstable power of the Full Resonance beginning to wane. He gasped for breath, a wave of exhaustion washing over him as his hair returned to its natural black, and the halo and wings disappeared. Deep within the pit, Kaito had returned to his normal self, unfused, and utterly spent.
'Master! Are you alright?!' Shikabanehime's frantic voice echoed in his mind.
'Kaito, we need to flee and fight him again next time,' Durandal urged, her voice filled with a desperate urgency.
The No Life King's body, still a writhing mass of bone powder and ethereal energy, began to slowly reform. The King's voice, now a low, grating whisper, filled the air. "To think you would inflict so much harm upon me. It has been so long since I have felt such pain." A new fury entered his tone. "I applaud you for that, but it's time to put your foolish ambition to rest. You cannot defeat me."
Kaito, summoning the last of his strength, manifested his wings and soared out of the hole. The No Life King watched him go, its eyes burning with hateful intent, before also soaring toward the sky after him.
"A flickering thought popped into my mind of letting you escape," the No Life King admitted, "but I decided that you're far too dangerous to my ambition if I were to let you live."
A blast of black flame slammed into the No Life King's back, halting his chase. It was Moque, soaring with Tamamo and Eleanor on her back. The No Life King scowled, raising a hand. "Gravitas Vinculum!"
An immense force of gravity slammed down on both Moque and Kaito, sending them hurtling toward the ground. Moque fought against the oppressive weight, shielding Tamamo and Eleanor, but the lich intensified his spell on her, grounding her in place.
The No Life King landed, standing over Kaito, who was struggling to move, pinned down by both his own exhaustion and the intensified gravity. Moque was immobilized and too far away to offer any meaningful assistance. The No Life King didn't give Kaito a chance to speak, casting an orb of pure darkness to finish him off.
But the orb was intercepted.
"You again," the No Life King hissed, the soul flame in its eyes flickering in outrage. "I thought your meddling was over once and for all."
A suit of armor, the Knight of Pitch-Black Soul, stood between Kaito and the No Life King. "I'm not one for leaving things unsettled," the knight said as his armor echoed. "Besides, a hero never truly retires."
With that, he pulled an object from his chest—a clear, smooth egg that pulsed with a faint, otherworldly light.
The No Life King spoke in a shocked and fearful tone. "That's impossible! I hid it in an unreachable location deep in the cosmos, within a maze of different dimensions. How did you get your hands on my phylactery!?"
The Knight's armor seemed to shift, his voice taking on a wry amusement. "In Wonderland, impossibility is merely a suggestion. And I've just redeemed a favor someone owed me."
With a firm grip, the Knight cracked the clear egg in two. A faint wisp of soul, the very essence of the No Life King's immortality, escaped and vanished into the ether. Ethereal chain burst from out of nowhere and wrapped around the No Life King's body and soul, dragging him downward with an unstoppable force.
The No Life King struggled, but it was useless. "I will escape! When I do, I'll get my revenge on all of you!" he screamed, his voice dissolving into a final, powerless echo as he disappeared.
The knight turned back to Kaito who had gotten back on his feet. "My debt has been cleared," the knight said. "Don't do anything so idiotic next time."
With a final piece of advice, the knight disappeared into a swirling portal.