Karate Island

"So, Mr. Gem, what do you think of joining my little crew here and becoming a pirate!?"

Rex smiled genially at the restrained Gem in front of him. While he hadn't even known that Mr. 5 was from the South Blue, it was an excellent opportunity to recruit the user of a strong devil fruit.

Not unlike Mr. 3 said, Rex believed that Gem was severely underusing his devil fruit. With a compendium of various anime characters in his mind, Rex could think of dozens who used explosions far better than Gem.

Still, Gem was being stubborn.

"I refuse! I'll never be a dirty, stinky pirate and I'll never work for one either! I'd rather blow myself up than join your crew." Gem shouted, closing his eyes and clenching all his muscles.

"If you want to activate your devil fruit ability, you'll find that you're unable to. Those handcuffs you're wearing are made of sea stone. On top of being one of the toughest materials in the world, it has the unique ability to prevent the use of any and all devil fruit abilities."

"What!?" Gem says incredulously. "That's no fair, fight me like a man!"

"I did, remember? You lost, and it wasn't even much of a fight."

"That was a sneak attack! Besides there were two of you, I want a one-on-one fight! Come on, put 'em up!"

"Gem my dear boy, a jacket may be warm and tender on the inside, but to outsiders, I am only harsh and abrasive. Put him back in the hole. I'll deal with him after Davy Back. Oh, and also do what we've agreed with him when he is in the prison."

Rex smiled cruelly at Gem, waving him away as he is dragged back by his two crewmen. Sometimes, Rex loved playing the cruel, brutal pirate. It was fun.

"Hey you'll regret this!"

Rex then sits down at his desk as if all is normal and sips a cup of tea.

"Now, let's deal with our itinerary for Karate Island."

(Five Days Later)

Karate Island, South Blue

"So, this is Karate Island, huh? I was expecting a green fishman to be here trying to sell me condos."

"Why would a green fishman sell you… con-dos?" Killer asked with genuine curiosity in his eyes. Often, Rex would just say odd things like that, or know about things he couldn't possibly know about. It was something Killer found rather odd about his captain.

"Never mind." Rex said with a sigh. "Now, there are two weeks until the Davy Back fight, so we have that much time to kill. Let's split up and try to learn something here on this island. It's not every day where we visit an island full of martial arts masters."

With this, the crew splits up, with Kid and Bonney going off to search for food while Killer leaves on his own to find a swordsmanship dojo. As for Rex, he was genuinely curious as to how many martial arts styles were present on the island.

Going to the main square of the island, Rex is astonished by the many schools giving out fliers.

"Visit the legendary golden body school! Where you will learn to be immune to the powers of all mortal weapons!"

"Come to the finger spear dojo. When you master the 'heaven-piercing finger' your finger shall pierce all!"

"Learn the body flickering art!"

"Go to the…"

Rex is simply baffled by the advertising of these dojos, which seemed to be so hyperbolic. As for the arts themselves, they disappoint him as all of them are just watered down forms of Grand Line martial arts.

For example, the 'heaven-piercing finger' seemed to be a weaker shigan. The 'golden body' was just Tekkai but worse. And the 'body flickering art' was just Soru.

There were others like the rain droplet fist, a copy of fishman karate, or the warrior's ballet, based off of Okama kenpo. Hell, Rex even found an imitation of Jio-Ken, that weird old man fighting style Lao G used.

Still, Rex decided that he should choose one of them so he could form an understanding such that when he encountered the real deal, he could learn it easier. Now, all he had to do was decide between Soru and Fishman Karate.

"Hey boy!"

Rex turns around, seeing an old man calling over to him. He was the only person who wasn't taking part in the frantic advertising.

The man seems to be all the way across the square, yelling over to him, but Rex gets the feeling that he's the only person who can hear him.

The man was extremely old, with wrinkles on his wrinkles. If Rex had to take a guess, he would guess that the man was no less than 100 years old, with an ancient feel about him.

"I can teach you real martial arts. Just come with me."

The man then left, without even bothering to turn back, almost as if he was confident Rex would follow him. Rex stares at the man's receding back, then back at the martial arts dojo's behind him, shaking his head.

"Hey old man, wait for me!" Rex shouts as he runs behind him.

While Rex couldn't be sure if this old man was a true martial artist, he knew for sure that at least he acted like one. Compared to those desperate fools, Rex felt that the old man might actually be able to teach him something.

By the time Rex has caught up with the old man, he has entered a small, dilapidated shack. There are faint letters carved on the shack which read, 'Trembling Fist Style'.

Rex enters the building, seeing the old man sitting on a mat in the lotus position.

"Do you know why I have called you today?" The old man says mysteriously.

"To teach me your martial arts style?"

"Hii ho hii ho. You sure are a presumptuous one." The old man said with a chuckle, "Even if I voided my minds contents and handed them to you, you may never learn the first move of the profound martial arts style I possess."

Rex frowned. This old man had read way too many Chinese martial arts novels.

"If you don't intend to teach me, why did you call me over here?"

"I never said that I do not intend to teach you. Only that I have no expectation that you will succeed." The old man explains, causing Rex to frown even more. "Do you see those boulders?"

Rex looks around the room, only to find a series of boulders of various sizes. The smallest boulder is only the size of a palm, while the largest is almost five meters in diameter.

"Do you want me to lift them? To prove my strength that is?"

"Hiihohiihohii! If you weren't at least that strong, I never would have picked you. No, what I want is much more difficult." The old man laughed boisterously before moving in a flash.

Suddenly, the old man was in front of a moderate0sized boulder, his fist flying towards it. Rex moves to stop him, worried that he would break his hand, only to see an astonishing thing.

The frail old man, who didn't look like he had the strength to truss a chicken, punched the boulder and it shattered into a million pieces.

"So you want me to destroy that boulder." Rex said, with fire in his eyes.

While that was a difficult task for him, Rex felt that he might be able to do that, given he used all his strength. After all, he was always training his strength, making sure he didn't fall behind Kid and Killer who were rapidly growing.

"Yes. But also no." The old man says sagely. "Pick up two of those stone fragments. Any two will do."

Rex obliges the strange request, only for his eyes to almost bulge out of his head as he does. The two rocks were almost identical.

Rex digs through the rubble furiously, finding the same trend, rock after rock. They were all identical.

"When you can wield the power of my art, and my art alone to destroy even the smallest boulder, I will have deemed you worthy of learning its true secrets."

"This art, what is it called?" Rex asked, having an odd suspicion in his head.

"It has many names, but it is most known as the art of Hasshoken."

"I see," Rex nods, a slight excitement welling up in his chest.

Hasshoken, the martial art used by Don Chinjao a famous pirate of the New World during Roger's era. With that art, and his unique horned head, Chinjao was able to split a continent in half. A man strong enough that Monkey D. Garp himself had to be dispatched to defeat him.

Rex couldn't believe that he had the opportunity to learn it.

"I will do my best to learn sensei."

Meanwhile, all across the island, similar experiences were occurring to Killer, Kid and Bonney.

"Bonney-chan, your jaw strength and stomach capacity are beyond my wildest imagination. With your ability to maintain your form and figure despite habitually consuming the food of 10 men, you will be perfect for my Minute Mastery martial art."

"Mini newt what, old man!?" Bonney shouts at the old chef in front of her. "Who cares? If you don't fill my plate in a min-ute you'll have some real problems!"

Bonney was starting to get sick and tired of the chef's ruthless badgering of her. He kept talking about how her 'mastication process was fascinating' and how her 'digestion mastery was profound'.

If it weren't for the fact that he was the best chef on the island, Bonney would have beat him up just for being annoying.

"Why don't we make a deal, Bonney-chan? In exchange for all the food you want, you come to my dojo and learn the Minute Mastery art. With your talent, one year, no, six months should be enough for you to learn it, after which you can leave."

"Wait, all the food that I want?" Bonney says, having ignored all that came after. "Why didn't you say so old man!? I'd love to learn your fillet mignon art!"

With Kid, he was being pestered by an old woman, who was jumping around him like a mosquito.

"Come on kid, why don't you learn my boxing style? It's the best boxing style in the world. Even that smelly brat Garp had to learn his fist of love from this old woman."

Kid grabs the old lady for the umpteenth time, throwing her away into the sky, only for her to reappear in front of hem.

"Stop pestering me old lady!" Kid shouted, tempted to use his Devil fruit to end this once and for all.

"Come on, just a few lessons. Masters of this art are all-powerful! They use mountains like sandbags, giants for sparring partners, you'll be unrivaled amongst all!"

"Shut up you old bag? Who cares about…" Kid pauses. "Wait, did you say unrivaled amongst all? Well then, show me something impressive!"

The old lady grins broadly. Earlier, she had not fought back against Kid because she was trying to get him to accept her teachings. But if she had his permission…

"Granny's kiss!" The lady shouts out, her fist blurring in front of Kid's face before he can even muster a response.

Bang!

Kid is thrown flying almost ten meters before he can slow himself down.

The old lady sighs. Age was really weakening her. In her prime, Kid would have gone flying for a kilometer, bursting through several buildings on his way.

But Kid only laughs uproariously. "Do that again!" He says, glowing with purple light.

Finally, Killer finds himself wandering through swordsmanship Dojos, one after another, seeing if he could find one worth learning at.

As Killer leaves his third Dojo, several twitching youths can be seen inside of it, their practice swords reduced to sawdust.

"You're pretty good with your swords." A blind old man chuckles, sitting in a meditative position with a pair of swords across his lap. "Care to test your abilities against an old senior like myself?"

Killer clenches his blades in his hands, staring at the old man. Ever since Kid and Rex had gotten their devil fruits, he had felt that the gap between himself and them had only been growing.

Rex was often the brains of the King pirates with Kid being the muscle. But what did that make him? The body Rex would possess? Even that seemed to be less and less frequent with Rex having his eyes on a permanent body in this Davy Back fight.

With that in mind, Killer vowed to become stronger, so he could stand on equal footing with his two brothers.

"Well then, let's fight, honored senior." Killer says, not underestimating the man in the slightest.

"Very well. I shall teach you the might of Wano's premier nitoryu swordsmanship!"

Then the two move in tandem, clashing their blades against each other.

As for why all these old martial arts masters seemed to come out on one day? The answer was simple to Rex.

Karate island was a land where martial arts aspiring youths from all four blues and even the grand line would visit. As such, when older martial arts masters who had reached their pinnacle began to age, they would visit this island in hopes of finding a student to continue their legacies.

But finding such a student was difficult, especially if your legacy was legendary. After all, martial arts needed more than just effort. It needed years of physical conditioning, hard work and talent, something that was hard to find all in one person.

However, the King pirates seemed to have this in spades. Even though they had been aged to 16, something that was reflected in their bounties, they were still extremely young to be as strong as they were.

In fact, even the regular crew members of the King pirates had all found masters, though they were in much more ordinary dojos than their officer counterparts. Rex had extreme standards for his crew with daily physical conditioning and training. Even the weakest crew members were superior to non-commissioned marines and the strongest non-officer members like Heat and Wire were as strong as weaker commissioned marines.

If Rex believed in such things as fate, he would believe that this was an almost fated encounter.

Still, fate or design, this encounter occurred, and now it was time to use it to its maximum.

"Let the training… begin!" The four masters said at once.

(Ten Days Later)

Rex walked around the town blindfolded, repeating what the old man had told him two days ago a hundred times in his head.

"You have mastered the heavenly stances with ease, which while impressive, is insufficient. Now, you must understand the true Dao of vibration. I task you to study the most profound of all natural vibrations, sound. Then you must you're your own vibration, your own Hasshoken, and master it."

Since then, the old man had kicked Rex out and left him to wander the streets blindfolded, vowing that if Rex took the blindfold off even once before discovering the true essence of sound, that he would expel him.

Rex was starting to get annoyed. What kind of martial arts training required you to 'comprehend the nature of sound'? This old man really needed to read less Wuxia.

Rex had mastered the actual stances and moves of Hasshoken in a week but had yet to produce even the weakest vibration. He was beginning to think that the old man was full of it and that those boulders were props.

Suddenly, as Rex is thinking, he accidentally bumps into a man, causing him to spill his hot soup all over his shirt. Not even feeling the light bump, Rex moves on, while the man fumes in rage.

"Hey you!"

Rex keeps walking, thinking the man was talking to someone else.

"The idiot in the blindfold, I'm talking to you!"

"What is it?"

"What do you mean, 'what is it'!?" The man roars, his face purple at Rex's nonchalant expression. "You spilled hot broth all over my shirt!"

"Ah, I see. I'm sorry, but as a blind man, I can't see where I'm going. I'd be willing to remunerate you for the damages."

"I'll remunerate your fa…"

Then the man pauses, just as he is about to threaten Rex. A cruel and wicked smile spreads across his face, if the man was blind that meant…

"Fine! But I'll warn you that my jacket isn't cheap. It was woven from the finest silks of the Grand Line, lined by the furs of the extinct wooly mammoth and made by a tailor who has been dead for 200 years. It is a priceless artifact worth no less than 100 million Berries! Then, this soup was made from the meat of a ten thousand year old sea king and the waters of ice continent in the New World, costing another 100 million Berries. Pay me that, or I'll pummel you into mincemeat!"

"Hmm, I see." Rex says, shaking his head. "How unfortunate, 200 million is outside of my price range. Had you been more reasonable and said something like a 20 thousand, I might have even paid it. A good jacket sold too expensive, is worth less than a mediocre one sold at a proper price. Disappointing, indeed."

The man face twists in rage as he grabs a massive Bo staff from his back. His voice seems to cause the ground itself to tremble.

"That's it! I'll show you the might of me, Bo Master, Joki the Unreasonable!"

Joki then leaps at Rex prepared to slam his bo staff down on him with his full might. Joki shouts out angrily as he attacks. Despite this, Rex doesn't move.

Several people cover their eyes, not wanting to see the gruesome scene that will likely follow.

"The true nature of sound." Rex mutters under his breath, recalling the trembling earlier from Joki's yelling. "Could it be…"

Just as the staff is about to descend, Rex twists his body to the side such that the staff passes right in front of his nose and slams against the ground where he was standing. Another loud sound echoes through the courtyard as the ground shakes once more.

"I see, I see." Rex mumbles, having a revelation.

"Are you making fun of me!?" Joki shouts, living up to his epithet of being unreasonable. "Are you saying that even you, a blind man, can see through my movements!? Then see through this!"

Joki continued his relentless assault, swinging his staff over and over again. Each swing is preceded by a shout, making them much easier to dodge.

Martial artists were idiots.

After the first strike, Rex's dodging only becomes more and more fluid. Rex begins entering a Hasshoken stance, making it clearer and clearer what the old man had meant.

Eventually, Rex can almost 'feel' a trembling vibration radiating out of the area where Rex assumed the man's mouth was. They were soundwaves being sent out almost one and a half times every second.

Frequency patterns.

Badump. Badump. Badump.

Then, rippling waves erupt out of Rex's palms, following the frequency of his heartbeat. Suddenly, he goes from the defensive to the offensive, thrusting his palm deep into Joki's stomach.

Joki ignores the attack, feeling that there was no power or substance to it, only to widen his eyes in shock as he suddenly feels his body tense up. Then, with no warning, the contents of his stomach rush out as he bends over and vomits.

"There's the rest of your 100 million Berry soup. Enjoy."

Rex then removes the man's jacket, which was, admittedly, a pretty nice jacket, then grins as he walks off, having started his mastery of Hasshoken. While Rex was nowhere near arrogant enough to believe beating Joki was equivalent to mastering the technique, it was a start.

Other members of Rex's crew are equally facing the heat of martial arts practice.

"Come on, Bonney-chan! I thought you were a world champion eater!" The old chef shouts, stomping down a dozen corndogs that are stuck outside of Bonney's throat. Drool leaked out of the corner of her mouth as her stomach was inflated like a balloon at its breaking point.

If any of her crewmates had seen Bonney, who was normally brash and aggressive, in such a state, they would be compelled to take a picture. Snap!

"No… no… no more food." Bonney groans out as she passes out for the umpteenth time. "No more Master Pinguis."

Never, in Bonney's entire life, would she ever believe that there was a time that she would beg for less food. But now, even the thought of eating made her want to vomit.

"What?" Master Pinguis asks, with his hand to his ear in an exaggerated motion. "You want more!? Of course, Bonney-chan."

If Bonney had heard this, she would have cursed the old chef's hearing problems and ran away. Unfortunately, she is awoken to the sensation of liquid chocolate being funneled into her mouth.

"Come on Bonney-chan! Be the stomach acids!"

Then, slowly, Bonney's stomach seems to deflate by a single centimeter.

Killer on the other hand, was baffled at how this old blind man kept beating him time after time on tasks that required sight.

It wasn't just swordsmanship too.

Chess games, cooking, climbing. All activities where one would need to see what they were doing.

Killer had no idea what the man wanted from him, but he kept muttering something about how the 'breath' was all wrong.

"Sensei, is it right now." Killer asks, arranging a house of cards for the tenth time.

"This is enough!" The blind man, who was ordinarily calm and sagely cried out. "It seems I must truly make you understand what a swordsman is."

The man then drew his swords and had a bloody aura rising about him. Snap!

However, of the four, the one who was in the worst state would be Kid.

"Come on! Everyone knows that the best way to get stronger is through beatings!" The old lady cried, looking at a giant iron ball in the center of his dojo.

After ten days of being ruthlessly pummeled by the old lady, Kid had used trickery to get her out of the room for a second to form his protective ball.

"GO AWAY, YOU SADISTIC OLD BAT!" Kid shouts, trembling from the many wounds on his body.

Kid had experienced bad fights. He had once picked a fight with a pack of wolves and almost had his arm gnawed off. But nothing in his life prepared him for the beating that the old lady had given him.

It was a relentless, consistent and never-ending assault of pain. The old lady's fists never caused any serious damage, just excruciating torture and Kid had had enough.

However, the old lady only smiled. "If you aren't coming out, then I guess I'll have to punch my way in." She grins as she retrieves spiked brass knuckles. "Little Kiddy, grandma's coming home for dinner!"

Snap!