Moreover, the Rumble-Rumble Fruit was far more well-rounded in its applications—if anything, it was even stronger than most Mythical Zoans.
Yamato had always been straightforward to the point of being simple-minded. The moment she heard this, her eyes brimmed with emotion. Without another word, she took the fruit and shouted at the top of her lungs:
"I won't let you down! I'll become as strong as Uncle King!"
"Eat it, eat it already! I wanna see the transformation!" Perona cheered from the side.
Under everyone's watchful eyes, Yamato steeled herself and took a huge bite.
In the next instant, her facial features twisted together in agony. The taste was easily a hundred times worse than expired fermented herring—but for the sake of getting stronger, she rolled her eyes and forced herself to swallow the entire fruit.
Then, something miraculous happened.
Yamato tentatively clenched her fist.
Crackle—snap—!
The sharp sound of electricity exploded outward. Blinding blue-white lightning burst from her fingertips, instantly wrapping around her entire body.
"Whoa! That's so tingly!"
Maria Fang and the others screamed and hastily retreated more than ten meters away.
Yamato let out an excited roar. A thick pillar of lightning shot straight into the sky, blasting a massive hole through the clouds overhead. The air was instantly filled with the acrid smell of scorching ozone.
"This is insane! I feel like my whole body's overflowing with power!"
She transformed into a bolt of lightning, flickering back and forth across the deck—so fast that the naked eye couldn't track her movements at all.
"This fruit's potential is limitless," Tenma commented with satisfaction. "Speed, power, range—it's top-tier across the board. Develop it properly, and even an Admiral would have to give you some respect."
After settling the matter of the Devil Fruit, Tenma pointed at the large bundle nearby.
"These are Skypiea Dials. They can store wind, fire, sound—take them back to Wano and let the craftsmen study them. We might end up with some serious black-tech."
Finally, his gaze fell on the massive Poneglyph.
"As for this—perfect timing. We have an expert onboard. Robin, it's yours."
Robin looked at the familiar stone slab, a complicated glint flashing through her eyes.
"Thank you, Lord Tenma… actually, I already took a look at it back in the ruins."
Tenma raised an eyebrow slightly. As expected of Robin—professional instincts through and through.
"What does it say? Is it the Void Century you've been searching for?" Maria Fang leaned over curiously.
Robin bit her lip, clearly hesitant.
That Poneglyph didn't record history at all—it contained information about a weapon capable of destroying the world.
Seeing through her concern, Tenma waved his hand casually.
"If you don't want to say it, then don't. No one's forcing you. I told you before—I'm not interested in Ancient Weapons, and I wasn't joking."
"What I, Tenma, want, I'll take with the sword in my hand. Why rely on external tools?"
He leaned lazily back in his chair, his tone as relaxed as if he were chatting about dinner, yet he suddenly dropped a depth charge of a statement:
"Judging by how tense you look, even if I didn't say it outright, everyone here could guess it—whatever's carved on that stone definitely has something to do with an Ancient Weapon, doesn't it?"
The moment those words landed, Lafitte, Kōshirō, and Hogback—who had seemed relatively calm just moments before—were instantly shaken to the core. Their expressions changed dramatically, eyes bulging as they stared at Tenma in sheer disbelief.
Since the veil had already been torn wide open, Robin pressed her dry lips together. After a brief struggle, she decided not to hide behind lies anymore.
She took a deep breath and nodded softly.
"Yes. It records the Ancient Weapon—Poseidon—and its exact location."
Just as Robin paused, about to explain the details carved into the Poneglyph, Tenma cut in first, as if he had already seen through everything.
"That so-called Poseidon… it's on Fish-Man Island, isn't it? Am I wrong?"
"Y–You… you even know that?!"
Robin's pupils shrank violently. She leaned back unconsciously, her voice completely unsteady.
"This… this is actually true?! Admiral—no, Shogun!"
Seeing Robin react as if she'd seen a ghost, the already-dazed trio felt their brains buzzing even harder, their entire worldview being shattered all over again.
"Yeah, what's so surprising about that?" Tenma shrugged. "Basic stuff."
—Basic my ass!
Hogback was screaming internally, his jaw nearly dropping to the floor.
That was Poseidon—the legendary Ancient Weapon with the power to command all the colossal Sea Kings across the entire ocean!
Something that could drive every ambitious madman in the world insane was being discussed so casually… right here, inside this ship's cabin!
"And if I told you that I don't just know about Poseidon, but also have a crystal-clear grasp of the other super-weapon—Pluton—its specs and its exact coordinates, would you believe me?"
Tenma curled his lips into a mischievous grin and continued bluffing without missing a beat:
"Don't forget, the ancient script carved into these Poneglyphs was originally created by Wano's craftsmen. As Wano's shogun, this counts as ancestral knowledge. It's perfectly reasonable for me to know a tiny bit of inside information, right?"
Naturally, this was complete and utter nonsense.
But everyone present was utterly intimidated—no one even thought to question him.
Tenma had his reasons for doing this.
First, everyone here was a trusted confidant, a die-hard retainer. Loyalty was maxed out; betrayal wasn't even a remote possibility. Even if these earth-shaking secrets slipped out casually, there was no risk of them leaking.
More importantly, by tearing away this final layer of mystery himself, Tenma aimed to completely shatter the thick psychological wall Robin had built around her heart.
And the results were immediate.
Unlike Lafitte and the others, who were still questioning their existence, Robin's sharp mind began racing after the initial shock.
Because of her tragic past, she had long believed that anyone who approached her had only two motives:
either to turn her in for the enormous bounty on her head,
or to exploit her ability to decipher Ancient Weapons and dominate the world.
When she first met Tenma, even though he explicitly said he wasn't short on money and didn't care about her bounty, she had already concluded that he must be after the Ancient Weapons.
As for his claims of "knowing many secrets" or "having no interest," she'd taken them as nothing more than smokescreens for hidden ambition.
But now, faced with this absurd yet undeniable reality—
Robin finally began to realize that what Tenma had said before… might not have been lies at all.
Maybe he truly hadn't kept her around for the sake of those world-destroying weapons.
Which meant there was only one explanation left.
He genuinely valued her—Robin herself—and sincerely wanted her to serve as his "chief steward."
Over the past few days, she'd already figured out what that position really meant:
a personal secretary plus housekeeper, rolled into one.
Just to recruit a capable secretary, Tenma was willing to risk offending the entire world by sheltering her—the "Demon Child" hunted relentlessly by the World Government.
No schemes. No ulterior motives.
Just because he valued her.
For a moment, the look Robin gave Tenma grew complicated. The deep-seated fear she held toward powerful figures slowly melted like ice under the sun, replaced by a warmth she had never felt before.
"Listen up, you lot! Get moving! Strip that ship ahead clean!"
"Kill all the men—chop them up and feed them to the fish! Capture the women alive! We'll sell them for a good price at Sabaody!"
On the Grand Line, aside from its unpredictable, soul-crushing weather, the one thing it never lacked was desperate pirates flooding in from all four seas.
Along this route, whether merchant vessels or passenger ships, if you didn't fly a flag with some serious backing, you wouldn't dare show your face on the open sea.
After all, for pirates, robbery was as natural as breathing.
That greedy roar came from a pirate warship flying a skull-and-crossbones.
They had sharp eyes. Spotting a massive, luxurious ship ahead—with no merchant insignia or famous pirate flag—they instantly developed murderous intent.
A vessel several times larger than their own—even if it carried no gold or treasure—was worth a fortune just for the hull alone.
They'd endured countless hardships on this journey and were about to reach Sabaody, the final stop of the first half of the Grand Line. What they lacked most right now was startup capital for venturing into the New World.
This was like someone handing them a pillow the moment they felt sleepy.
Under the wild encouragement of their one-eyed captain, the pirate ship adjusted its sails and charged forward like a shark that had smelled blood.
They had no idea they were already the fifth batch of hard-headed fools to try this.
If even one of their predecessors had succeeded, it wouldn't have been their turn to become the next unlucky victims.
Suddenly, streaks of dazzling sky-blue electricity erupted violently in the air, crackling with scalp-numbing explosions.
Those tiny arcs converged in an instant, forming a solid beam of terrifying lightning that shot straight into the heavens, as if piercing the sky itself.
An invisible pressure descended like a mountain.
The battle-hardened pirate captain frowned, instantly sensing something was wrong.
The sky overhead seemed to darken. The air filled with the smell of burning and restless static.
Just as he instinctively opened his mouth to shout "Evasive maneuvers!"—
BOOOOM—!
A colossal lightning pillar, tens of meters thick, slammed straight down from the heavens like divine punishment, striking the pirate ship's deck dead center.
There was no suspense.
The entire vessel was instantly engulfed by annihilating thunder.
Under the combined onslaught of extreme heat and shockwaves, the once-sturdy hull crumbled like papier-mâché, disintegrating into countless flaming fragments.
The scorching blast wave, mixed with raging electricity, churned the sea into towering waves—so intense that even the surrounding seawater was partially vaporized.
This world-ending strike naturally came from Yamato, who had only recently eaten the Rumble-Rumble Fruit.
Tenma had thought it through clearly.
Since the Grand Line never lacked idiots who volunteered their lives, he simply left Skypiea's Shandora floating ten thousand meters above the sky, with Kōshirō and the voluntarily-staying Hogback guarding it.
Meanwhile, he himself sailed openly across the sea in this ship.
These blind pirates—just like those back in the West Blue—became live targets for training his subordinates.
That said, there weren't many onboard who actually needed this kind of real combat practice anymore. Mostly Perona, Maria Fang, and Yamato—occasionally Lafitte joined in when his hands got itchy.
Kuina and Zoro were still too young, their combat power not yet formed. Robin, on the other hand, was mentally a pure civil servant—she had no interest in fighting.
Compared to battle, she preferred curling up in a quiet corner reading. Recently, she'd even been obsessively studying management science and professional secretary skills.
Looking at the still-smoking sea in the distance, even though she'd already seen this scene more than three times, Perona still paled and shrank her neck.
"Looks like Yamato's getting more and more proficient with the Rumble-Rumble Fruit," Lafitte said, pressing down the brim of his hat, his tone filled with awe. "This kind of natural, heavenly power… no matter how many times you see it, it still makes your soul tremble."
"Hehe, that's all because Tenma taught me!" Yamato said proudly, waving her right hand, which still crackled faintly with electric arcs.
To be honest, Yamato had initially known nothing about the deeper principles behind electricity.
But after several days of Tenma's "hell-level tutoring," she'd developed an extremely deep understanding of the Rumble-Rumble Fruit's properties—and could even extrapolate new techniques on her own.
Enel's life-saving electrical defibrillation?
Using electromagnetic waves to amplify Observation Haki?
Yamato already had those down pat.
Electricity was a revolutionary discovery. The depth hidden within it went far beyond simply zapping people to death.
Once Yamato's control improved another level, her versatility would utterly eclipse that self-proclaimed "god" Enel.
Of course, Tenma was already planning ahead.
Once they returned to Wano, he'd hire a few reliable scientists at a high price to give Yamato a proper crash course in physics.
Tenma himself, as a transmigrator, only knew surface-level concepts—electric fields, electromagnetism, that sort of thing. Ask him for deep theory, and he'd be lost too.
Fortunately, the One Piece world was full of black-tech geniuses. Their knowledge and imagination were more than enough to guide Yamato's development.
At the moment, Yamato—who was happily playing with little Nami alongside Maria Fang—had no idea that her fate had already been sealed.
An inhumane supplementary-class hell awaited her.
Suddenly, Yamato's beast ears twitched.
She turned toward Tenma.
"Tenma, there's another ship on our starboard side. Feels weird—doesn't seem like a pirate ship, but not a merchant vessel either."
Thanks to her natural talent, combined with electromagnetic amplification of her Observation Haki, Yamato's sensing range now covered nearly ten nautical miles around the ship.
Anything that entered this massive detection net couldn't escape her notice.
Clearly, a fast-moving ship had just crashed straight into her still-active perception field.
"It's heading toward Sabaody Archipelago. No skull flag, no cargo markings…"
Lafitte stroked his chin thoughtfully.
"Could it be one of those legendary human-trafficker ships?"
The moment he heard "human traffickers", combined with this particular point in the timeline, a spark flashed through Tenma's mind.
Could it be… those three unfortunate sisters?
No way it'd be that coincidental, right?
Though doubtful internally, Tenma kept a calm expression and turned to Lafitte.
"Bring us closer and take a look. We've got nothing better to do anyway. If it really is a slaver ship, I'd like to see which unlucky souls got caught up in it."
"As you command, my Admiral."
Lafitte gave an elegant bow and immediately went to the helm, adjusting course and accelerating toward the direction Yamato indicated.
Though the other ship was also speeding up, it was no contest against Tenma's specially modified vessel—especially with Yamato occasionally "helping" by covertly boosting it with electric propulsion.
Before long, a medium-sized passenger-ship-style vessel appeared clearly in their forward view.
The mountain-like bulk of Tenma's ship naturally alarmed the target immediately.
"Boss! This is bad! A gigantic ship is closing in from behind! Looks like it's coming straight for us!"
Hearing the lookout's panicked shout, a burly man with a face full of scars growled,
"What are you panicking for?! Did you get a good look at who they are?"
The young underling with binoculars swallowed hard as he spoke, his voice trembling:
"B–Boss… there're only two men onboard. The rest—five or six—are all women and kids! And… my god, those women are all top-tier! The figures, the looks—absolutely premium! And there are kids with horns on their heads—rare specimens!"
The more he spoke, the more excited he became, eyes bloodshot as he turned back and yelled:
"And I checked—their ship's completely bare, no flags at all! Those two men—one looks like a butler, the other doesn't even carry a weapon! Smooth-skinned and refined—definitely some noble brat out sightseeing with his family!"
(To be continued…)
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