The Eclipse Cabin, Jeno's Laboratory.
Intense, blinding sparks and the high-frequency screech of high-grade alloy cutting tools had echoed across the wide workspace for nearly ten continuous hours. Aside from taking brief breaks to ingest raw caloric fuel up on the main deck, Jeno had devoted the entirety of his industrial processing power to the three-meter-long deep-sea invertebrate.
"The final section of the memory alloy armor plate is stabilized... neural connection confirmed... high-pressure induction valves locked down... Complete!"
Jeno wiped a heavy line of sweat from his forehead, tracing a look of pure, unadulterated satisfaction across the operating platform where his newest masterpiece lay.
At this hour, the soft-bodied sea monster's original, shredded biological tissue had vanished completely under the design. In its place was a specialized cybernetic heavy armor framework—remarkably thin yet incredibly dense—boasting a dark silver, streamlined finish lined with rows of vicious, predatory barbs.
The chassis didn't merely conform flawlessly to the invertebrate's soft, octopus-like musculature; it extended past its lower matrix into a long mechanical tail forged from articulated segments of memory alloy, capped by a razor-sharp inverted triangular blade. Even along the lateral margins of the carapace, two high-pressure hydraulic spray valves engineered to open and close on command had been discreetly mapped into the infrastructure.
"Chopper, introduce the blue nutrient solution. Initiate the awakening sequence," Jeno said, snapping his fingers.
"On it!"
Chopper, who had been monitoring the vitals from the margin, skillfully utilized his hooves to inject a high-potency, pale blue compound directly into the cephalopod's stabilized circulatory paths.
A few seconds ticked past.
"Gurgle... Gurgle?"
The deep-sea beast, having successfully bypassed a terminal selection and undergone a total structural transformation, slowly unsealed its massive, dark yellow eyes.
A primitive confusion clouded its gaze. It attempted to flex its torso, only for its nerves to register an entirely foreign, metallic resistance along its spine. A rapid, alarmed trill escaped its air valves.
"Lower your panic, companion. I'm anchoring your position."
Shark, who had remained standing guard beside the operating table like an immovable gray monument, strode forward. His perennially flat, triangular eyes were unusually soft, carrying a rare, quiet warmth as he reached out.
His large, rough, dark bluish-gray palm settled gently against the creature's cold, metallic chassis.
"Gurgle!!!"
The microsecond its eyes registered Shark's face, the anomalous sea beast instantly discarded its terror regarding the mechanical shell. Letting out a long, joyful trill, the high-density suction organs lining its abdomen wriggled frantically, launching its mass off the operating platform. Like a massive octopus reclaiming its reef, it wrapped its tentacles tightly around Shark's extended arm, desperately rubbing its soft underbelly against his skin.
This display of absolute, unreserved dependence left even the stoic Fish-Man vanguard somewhat at a loss, his posture freezing.
"Incredibly moving..."
Chopper, watching the interaction from the corner, had tears welling within his large eyes. With his fruit-enhanced linguistic translation active, he could parse the creature's internal thoughts flawlessly; the microsecond its awareness cleared, its mind had been completely flooded with a frantic call for Shark's presence.
"Shark, your ledger never specified how your paths crossed with this anomalous invertebrate in the lower seas," Jeno remarked as he began clearing his workstation tools.
Sabo and Carina stepped through the laboratory doors to audit the completion, their ears tilting forward to catch the data.
Shark remained still, feeling the familiar, cold pressure of the tentacles constricting his forearm before he let out a low breath.
"The crossing occurred roughly six months prior to my integration with the Eclipse."
Shark's voice was a deep, resonant bass, his thoughts tracking back to the lonely sea lanes he had navigated before meeting Ace.
"I was drifting through these specific quadrants at the time. During my transit, I intercepted an armed slave brig transporting human stock and rare biological assets to the auctions of the Sabaody Archipelago. I executed the slave hunters and shattered the iron enclosures across the lower decks."
Shark's eyes lowered to trace the dark silver carapace of the beast clinging to his arm.
"This creature was isolated inside one of the primary reinforced water tanks. Because its morphology was entirely irregular and it possessed a unique capability to compress water, the collectors intended to trade it as an exotic pet. Once I cleared its seal, it systematically shadowed my navigation pattern like a trail I couldn't shake loose."
"Throughout those weeks, it swam wherever my path drifted. Even when our trajectory crossed the hunting grounds of apex deep-sea monsters, it would repeatedly advance, attempting to utilize its thin, low-pressure water spouts to provide cover for my flanks."
Shark let out a quiet sigh. "But my long-term calculation demanded an attack on the central transport fleets of the Celestial Dragons. An engagement of that magnitude carried far too much friction for a civilian beast. It possessed zero martial cultivation—only primitive survival instincts. I refused to let its lifeline be snuffed out in a human war, so I forcibly drove it into the deep trenches, clearing it from my wake. I calculated it would return to the lower sea bed and live out its years in peace."
"Coo! Coo-coo-coo!"
Hearing the summary, the sea monster wrapped around his arm began to thrash its tentacles in agitated protest, its long mechanical tail tapping lightly against Shark's shoulder blade as if reprimanding his logic.
"What is the translation on that frequency?" Sabo asked, turning his head toward the ship doctor.
Chopper immediately adjusted his hat, translating the technical signals: "It states that returning to the empty trenches was never its intention! It notes that it has registered itself as your subordinate, and it will shadow your boots through any sea gate on the map! It also highlights that after you cut the link, it spent months navigating these exact coordinates looking for your shadow, which is why it was ambushed by that large apex predator. If your boots hadn't cleared the distance when they did, its path would have ended permanently!"
Hearing Chopper's raw translation, Shark's chest tightened a fraction of an inch.
On this lawless, blood-stained ocean, an alliance that permitted an outlaw to entrust their spine to another without a sliver of reservation was an asset of immeasurable mass. The absolute sense of identity he had failed to secure within the ranks of the old Sun Pirates had finally crystallized aboard the Eclipse. Even the primitive beast he had discarded had fought through half the Grand Line simply to re-align with his shadow.
"I will not sever the link again," Shark whispered.
He extended his left hand, his fingers patting the ultra-hard titanium composite shell Jeno had engineered. "With this armor shielding your tissue, you will function as the strongest baseline protecting my back from this hour forward."
"Gurgle!!!"
The cephalopod unleashed a high-frequency, excited trill, its mechanical tail swaying in perfect harmony with Shark's vow.
"The parameters are whole, Shark. What is the designation on its profile?" Jeno asked with a wide grin.
Shark looked down at the dark silver spikes, a fitting, razor-sharp name surfacing within his calculations.
"Let's log its asset name as... Samehada."
Shark delivered the name with absolute, unyielding seriousness.
"Samehada? Shark-skin... an exceptional match for your morphology," Jeno chuckled.
Shark relaxed his arm, issuing his first tactical command to the symbiote: "Samehada. Possession frame."
"Gurgle!"
The beast named Samehada flipped its mass with surgical timing, its three-meter-long body flattening itself directly against Shark's immensely broad, gray shoulders.
The high-density suction pads lining its underbelly adhered with hydraulic force to the Fish-Man's thick muscle groups, anchoring its weight as if it had grown directly from his biology. The dark silver, spiked armor—forged from memory alloy and titanium composite—perfectly covered Shark's entire upper back, his shoulder blades, and extended down to seal his lower lumbar region. The long mechanical tail, tipped with its inverted triangular blade, hung between his legs, swaying flexibly in perfect synchronization with his breathing like a natural extension of his chassis.
Shark led the symbiote out through the laboratory hatches onto the open main deck, turning his stance toward the open sea.
"Fish-Man Karate: Five Thousand Tile True Punch!"
Shark drove his right fist forward in a sudden, concussive snap!
Simultaneously, the high-pressure alloy induction pumps mounted on both sides of Samehada's mechanical carapace engaged instantly with an industrial whine. A violent, hyper-pressurized column of seawater erupted in perfect synchronization with Shark's physical strike, traveling along his trajectory to punch through the empty air.
Boom—!
The combined kinetic force smashed into the ocean surface far below, carving a massive, hollow dent into the waves before the water could collapse inward.
"Magnificent output!"
Watching the terrifying multiplication of Shark's destructive metrics, Jeno leaped into the air, clapping his hands in technical ecstasy.
Shark felt the unyielding, absolute structural hardness shielding his spine, matched by the exhilarating sensation of commanding a pressurized torrent of water on demand. A slow, rare smile touched his gray features.
With Samehada anchored to his marrow, his Fish-Man Karate could now dictate absolute dominance even on dry, land-based battlefields where natural water was completely scarce.
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