The air above the churning grey sea crackled with the aftermath of unleashed power and the promise of imminent violence. Obito stood immobile within his Kamui vortex, a dark silhouette against the swirling mist, his orange mask betraying nothing, yet his lone Sharingan fixed on Naruto with chilling, analytical intensity. Kisame Hoshigaki grinned, a predator scenting blood, his massive sword Samehada shivering eagerly in his grip, its scales rippling as it sensed the potent chakra radiating from Naruto – a volatile mix of Rinnegan authority, stolen Three-Tails energy, and the unsettling hum of Kaguya-cells. The cloaked Akatsuki member beside Obito remained an enigma, radiating cold, focused menace.
Naruto stood his ground, seawater dripping from his dark attire, the bone-white flecks beneath his skin pulsing with a faint, cold light visible even through the fabric. The whispers from the integrated structures surged, resonating discordantly with the ancient power radiating from Obito. The cold core of vengeance within him hardened, locking onto the immediate threat: Obito blocked access to Yagura, the key to the Mizukage's core data scroll and the vital tissue sample Orochimaru demanded.
"Last chance, Kyuubi brat," Obito's distorted voice cut through the alarms blaring from the disabled 'Karasu' and the roar of the sea. "Walk away. Or become another casualty of a war you don't understand."
Naruto didn't dignify the demand with words. His response was pure action. The Rinnegan flared, its outermost ring blazing violet.
**Shinra Tensei: Directed Repulse!**
Not the wide-area blast he'd used against Root. This was a focused, scything wave of pure repulsive force, aimed not at Obito himself – who could phase through it – but at the deck *between* him and the still-dazed Yagura. The reinforced metal screamed as it tore upwards in a violent ripple, creating a jagged, smoking trench and forcing Obito to momentarily solidify or be shoved aside. Kisame roared, leaping forward, Samehada raised high for a crushing blow.
Naruto didn't engage the swordsman. He moved *through* the chaos created by his Shinra Tensei. As Kisame's massive sword descended, Naruto's right hand snapped up.
**Intrinsic Armament: Bone Shield.**
A curved plate of gleaming, seamless white bone erupted from his forearm, interposing itself between him and Samehada with shocking speed. The impact was thunderous. *CLANG-SHRIEK!* Samehada's hungry scales met the unyielding bone. The sword didn't absorb; it *rebounded*, sending shockwaves up Kisame's massive arms, his grin faltering into surprise. The bone shield held, unmarked.
In that instant of Kisame's stumble, Naruto was already past him. He closed the distance to Yagura in a blur. The Mizukage's remaining guard lunged, a water spear forming in his hands. Naruto's left hand shot out, palm open.
**Preta Path: Targeted Drain.**
The guard's chakra was ripped from him in a visible torrent, collapsing him instantly. Naruto absorbed the surge, feeding the Rinnegan's hunger and countering the drain from his own abilities. He reached Yagura. The young Mizukage's eyes, still glazed by Obito's genjutsu, flickered with desperate, trapped awareness. Naruto's hand clamped onto Yagura's shoulder, fingers digging in. Not for comfort. For extraction.
**Chakra Extraction: Isobu Resonance!**
He didn't need the full beast. He needed a signature, a catalyst. The Rinnegan focused, bypassing Obito's genjutsu shackles momentarily, tapping directly into the turbulent sea of Three-Tails chakra churning within Yagura. He siphoned a concentrated stream – not raw power, but the unique, watery *resonance* of Isobu itself.
Yagura gasped, a shudder wracking his body as the invasive pull disrupted Obito's control for a split second. Naruto's other hand, guided by the Rinnegan's sight and the Kaguya-cells' unnerving precision, plunged a small, bone-white scalpel that *grew* from his fingertip into Yagura's exposed forearm. A quick, precise incision. He withdrew a minuscule vial of blood and tissue, the sample already sealed within the self-generating bone capsule. Simultaneously, his free hand snatched the cylindrical data scroll secured at Yagura's belt.
Task complete. He released Yagura, shoving the dazed Mizukage back towards his recovering guards. Retrieval achieved.
"Insolent *pest*!" Obito's voice held a flicker of genuine anger now. The Kamui vortex swirled violently. He lunged, phasing through Naruto's instinctive defensive stance, his hand aiming to grasp Naruto's head, likely to wrench him into the Kamui dimension.
Naruto didn't try to dodge the intangible hand. Instead, he focused inward, on the volatile mix within him – the stolen Isobu resonance, the Rinnegan's power, and the surging, reactive energy of the Kaguya-cells. He channeled it all, not outward, but into a localized defensive pulse centered on his own body.
**Chakra Disruption Field: Isobu's Echo!**
A sphere of violently churning, pressurized *water* chakra exploded outwards from Naruto's body, infused with the unique disruptive frequency of the Three-Tails. It wasn't an attack; it was pure, chaotic interference.
Obito's hand, phased but still connected to the physical plane through his technique, met the churning field. Kamui relied on precise spatial manipulation. The Isobu-echo field, resonating with the power of a Tailed Beast, created a localized maelstrom that violently *disrupted* the delicate chakra harmonics maintaining Obito's intangibility. For a fraction of a second, Obito's hand *solidified* within the field.
***CRACK!***
A bone spike, needle-thin and impossibly hard, shot from Naruto's shoulder, piercing Obito's solidified wrist. Not deep, but enough to draw dark blood and elicit a sharp, distorted hiss of surprise and pain. Obito recoiled violently, yanking his hand back into the safety of the Kamui vortex, clutching his wrist. His Sharingan blazed with fury and a flicker of something else – shock at the unexpected counter.
Kisame roared, charging again, Samehada screaming for chakra. The cloaked Akatsuki member finally moved, hands flashing through seals – dark, crackling energy gathering around them.
Naruto didn't stay. He had what he came for. The Isobu-echo field dissipated. He triggered the miniature explosive tag concealed within the bone earpiece Kabuto had given him – not to communicate, but as a signal.
***BOOM!***
A small, localized detonation near the ship's remaining chakra battery created a plume of smoke and sparks. In the momentary confusion, Naruto dove backwards off the deck, plunging into the cold, churning sea. He propelled himself downwards with powerful kicks, the Rinnegan guiding him through the murk, his chakra signature masked by the lingering Isobu resonance and the alien nature of his own energy.
He sensed, rather than saw, Obito's furious gaze piercing the water, Kamui warping the space above. He sensed Kisame's predatory frustration. But they didn't follow. Retrieving Yagura was their priority now; the interloper who had drawn blood from the phantom was secondary.
Naruto swam, the bone sample vial and data scroll secure within a self-sealing pocket of bone that had formed beneath his ribs. The whispers of the Kaguya-cells were louder now, excited, resonating with the echoes of the Three-Tails' power he'd wielded and the brief taste of Obito's blood. The Rinnegan's drain gnawed, but the stolen chakra from the guard and the lingering Isobu energy sustained him.
He reached the designated extraction point – a submerged sea cave miles down the coast. Kabuto was already there, waiting in a small, chakra-cloaked submersible.
"Mission parameters achieved?" Kabuto asked smoothly, his eyes scanning Naruto for injuries, lingering on the faint white glow still visible beneath his skin and the sealed puncture on his shoulder where the bone spike had retracted.
Naruto wordlessly handed over the bone vial and the data scroll. He climbed into the submersible, collapsing onto the cold metal bench. The adrenaline surge faded, replaced by crushing fatigue and the insistent whispers. The Isobu resonance within him, foreign and turbulent, churned against the Kaguya-cells and the Rinnegan's authority, creating a dissonant storm inside him. He closed his eyes, focusing on the cold core, the anchor of his vengeance.
"Lord Orochimaru will be pleased," Kabuto murmured, stowing the precious samples. "The field test was… illuminating. The resonance cascade achieved… particularly against the Kamui user." He started the submersible's silent engine. "Rest, vessel. The integration proceeds. The next phase awaits."
As the craft slipped silently through the dark water, away from the mist-shrouded chaos of Kiri, Naruto felt not triumph, but the deepening chill of transformation. He had drawn blood from a ghost, stolen from a beast, and bargained with a serpent. The cost was etched into his very cells, whispering of an ancient legacy he was becoming. He was no longer just the vessel of the Rinnegan. He was becoming a nexus of stolen powers and monstrous inheritance, a weapon forged in desperation, hurtling towards an inevitable confrontation where the only certainty was the fire of his own damnation. The hunter had tasted blood, and the shadows were gathering in response.