As Benimaru offered all the help he could give to the Revolutionaries, Dragon said that it would not be without payment. In return, Dragon offered to teach Benimaru all of the martial arts he knew, ranging from the Six Powers and Life Return, which he learned from the Marines, to Fishman Karate and Ryusoken.
Starting from day one, Dragon explained the concepts behind the Six Powers, one by one. He knew that Benimaru's physical abilities were more than sufficient to practice them. Benimaru, who possessed three times the maximum comprehension of a human, quickly understood each concept, shocking Dragon with his potential. Dragon then went on to explain the principles behind Fishman Karate and Ryusoken, which Benimaru also grasped almost immediately, allowing him to learn all of Dragon's martial techniques in just a single day.
Benimaru and Dragon then agreed that sparring while applying the martial arts would be the best way to master them and use them fluidly. Starting from day two, the two began sparring against each other.
"Since you've learned the martial arts in a moment, it shows that you have great comprehension, perhaps the greatest of all. But comprehension and application are two different things. So, let's test your strength," Dragon said to Benimaru, who immediately agreed, seeing it as a chance to increase his power.
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Benimaru and Dragon stood still on a random island that Kuma had sent them to, wanting to fight using all of their strength and capabilities, excluding their Devil Fruit abilities. Both used Soru to approach each other at high speed, throwing punches while simultaneously using their other arms to block.
Benimaru then attacked with a straight knee, but Dragon freed his arm to punch the incoming knee. The moment Dragon freed his arm, Benimaru immediately followed with a twisting kick aimed at Dragon's head. Dragon dodged at the last moment and delivered a push kick to Benimaru, who couldn't evade as he was mid-air.
As Benimaru was knocked back, Dragon used Fishman Karate to gather moisture from the air and launched it toward Benimaru. In response, Benimaru used Fishman Karate himself, controlling the sharp water Dragon had just used and redirecting the attack back toward him.
Dragon reacted instantly, shifting his stance as he redirected the redirected water strike with a precise Ryusoken technique, causing the water to spiral harmlessly into the air. Benimaru took advantage of that split-second opening, using Geppo to launch himself high into the sky before crashing down with a devastating Tekkai-enhanced axe kick, aiming straight for Dragon's shoulder.
Dragon sidestepped at the last possible moment, the ground beneath him cracking from the force of Benimaru's kick. Without missing a beat, Dragon used Shigan to strike at Benimaru's ribs—fast and sharp like a bullet. Benimaru grunted as he twisted mid-air to deflect most of the impact, countering with a flurry of rapid Rankyaku slashes aimed at Dragon from multiple angles.
Dragon smiled.
Using his own Rankyaku infused with Ryusoken's claw-like precision, he sliced through Benimaru's air blades one after another, each clash sending shockwaves across the island. Palm strikes, kicks, and counters exchanged in a blur, both fighters weaving between offense and defense as if dancing to a rhythm only they could follow.
Then, Benimaru disappeared.
Dragon's eyes narrowed. "Kami-e." He let his body flow with the air, just in time to avoid Benimaru's surprise attack from behind.
"You're getting faster," Dragon said, as he noticed that Benimaru was mixing the different moves and martial arts more fluidly.
"Not fast enough," Benimaru replied, already moving in with a combination of Shigan and Fishman Karate, his fingers crackling with internal force as he attempted a hybridized strike.
This time, Dragon didn't dodge. He caught Benimaru's wrist mid-strike and pulled him into a powerful hip throw, slamming him into the ground. Before Benimaru could recover, Dragon was already mid-air, using Life Return to manipulate his muscles and increase the force behind his falling strike.
Benimaru raised his arms in an Iron Body (Tekkai) block just in time, the shockwave blasting a crater beneath them.
For a moment, both remained still, breathing heavily, dust and debris swirling around them.
Then Benimaru grinned. "I get it now... It's not just about the technique, but how you connect them. Flow over force."
Dragon nodded. "Exactly. You don't fight with just your body—you fight with your will, your mind, your instincts. You're learning fast."
Benimaru stood, dusting himself off. "Again."
Dragon smiled. "Good. Let's continue."
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The training continued for a full month before Dragon had to leave—his responsibilities as a Revolutionary leader demanded his attention. Benimaru had progressed immensely. His body had become so durable that his skin was now invulnerable to damage, akin to Big Mom's iron body, but on an even harder scale. This was proven when Dragon, using Armament Haki, punched Benimaru with full force, yet failed to even scratch him.
However, the greatest improvement Benimaru achieved was in his fire generation. He had developed the ability to compress his flames, similar to how Ozai from legend compressed fire to make it explode on contact, except Benimaru's fire now burned at an even higher temperature.
Kuma then arrived at the island to return everyone to Swallow Island using his Paw-Paw powers. Upon their arrival, they were greeted by Shachi, Penguin, Bepo, Law, Wolf, Ginny, and Ivankov. Kuma took over the training of the four future Heart Pirates—a request made by Benimaru. Kuma, ever reliable, was more than willing to comply. The group now had a foundational understanding of combat, with Law beginning to train seriously with a sword.
"Thank you for the lessons and training you provided, Dragon-san," Benimaru said with genuine respect. "I managed to grow this strong despite the little time you had available."
"You grew this fast because of your efforts and immense talent," Dragon replied, equally sincere. "Even with all my experience, I've never met someone quite like you. If you ever decide to join the Revolutionaries—or if you need assistance—just give me a call." Dragon had already given Benimaru the number to their Den Den Mushi.
As Dragon and Benimaru exchanged farewells, Kuma and Ginny also said their goodbyes to the four young Heart Pirates. They all deeply respected Kuma as their teacher, but their hearts were especially heavy thinking of Bonney. She had become like a little sister to them, especially to Law, who saw in her the image of his long-lost younger sister.
"Master Kuma, please take care of Bonney for us," Shachi, Penguin, and Bepo said through tearful voices. They didn't know when they would see the cheerful Bonney again, and the parting left them emotional. Law, though more composed, was just as saddened—another painful goodbye.
"Don't worry," Kuma said with calm reassurance. "Bonney is in good hands with us. I will make sure of it."
As the final farewells were exchanged, Dragon made one last attempt to recruit Benimaru into the Revolutionaries—but Benimaru declined, once again.
In parting, Benimaru handed over another sample of a weapon he had developed: a 16-inch/50-caliber Mark 7 gun, along with detailed instructions on how to manufacture it, including the specialized ammunition it required.
Dragon accepted the gift with a nod of gratitude and, in return, handed Benimaru a journal that he found from the punk hazard when it was abandoned by the scientist, it was based on Vegapunk's research on Devil Fruit cloning.