At Aokiji's suggestion, Yoriichi Tsugikuni really did get a bamboo sword, and Aokiji, true to his word, immediately used his Devil Fruit ability to create an ice sword.
Perhaps calling it an ice sword isn't quite accurate; although the weapon Aokiji created was sword-shaped, it wasn't the sharpened kind. The blade was essentially a stick, suitable for sparring without harming Yoriichi.
The two on the deck quickly engaged in combat.
Aokiji's physical skills, not utilizing his Devil Fruit ability, were indeed lacking, only slightly suppressing Yoriichi, a "new generation rookie."
During their fight, Aokiji demonstrated several other Marine Six Powers.
He predicted the opponent's attack direction based on the airflow generated by their attack, controlling his muscles to deflect the force. He used
the advanced technique of Shave, Moonwalk, to briefly levitate by compressing air with high-frequency stomping. He
also used the Tempest Kick, a high-speed kick that creates invisible air blades.
Gathering all his strength at his fingertips, he unleashes a finger gun, comparable to a bullet, capable of easily piercing the human body.
He also accelerates blood flow, channeling power into his honed body, making it as strong as steel, impervious to bullets and slashes—a defensive technique called "Iron Body."
These five abilities, combined with the high-speed movement technique—Shave—constitute the complete Six Styles of the Navy.
During his sparring with Yoriichi, Aokiji demonstrated each technique, while Yoriichi, through his Transparent World, easily grasped the essence and principles of the Six Styles.
In short, these techniques are all about controlling the body, but Yoriichi's greatest strength wasn't the terrifying power to unleash a hundred slashes in an instant, but rather his control over his body.
In the Demon Slayer world, anyone who has mastered Breathing Techniques to the extreme and reached the Transparent World realm possesses terrifying control over their muscles.
This terrifying control, coupled with his inherently terrifying physical abilities, allowed Yoriichi to perfectly replicate the Six Styles the instant he grasped their essence.
As Yoriichi became more proficient in using the Six Styles of the Navy, he began to consider how to integrate them into his combat.
"The power generation of the Finger Pistol is similar to the Sun Breathing Seventh Form's Benificent Radiance."
"It's just that one concentrates power at the fingertips, and the other at the tip of the blade."
"For me, the Finger Pistol's effect is not obvious."
"While Moonwalk allows me to briefly levitate, swordsmanship only unleashes its full power when grounded. In normal combat, it can only be used to catch opponents off guard."
"The Shave technique is quite good; it allows me to connect sword techniques more smoothly during attacks."
"Storm Kick is very useful. If this technique is used with a sword, wouldn't it be a flying slash?"
"As for Iron Body... hmm! This technique is what I need most right now. As everyone knows, swordsmen's defenses are very fragile!"
"Clang!"
"Clang!"
"Clang!"
On the deck, Yoriichi's bamboo sword and Aokiji's "ice pop" clashed rapidly, producing a series of muffled thuds. Yoriichi's attacks were fluid and smooth. Even without using sword techniques, each move flowed perfectly.
While the power of each attack wasn't particularly strong, they were all aimed at openings in Aokiji's defenses.
Aokiji, meanwhile, was simply defending with his "ice pop," relying on his superior speed and the Observation Haki he secretly used to accurately block Yoriichi's attacks.
However, whenever Aokiji tried to switch from defense to offense, Yoriichi would always change his tactics, forcing Aokiji to abandon his offensive and switch to defense.
Sometimes Aokiji wondered if Yoriichi also possessed Observation Haki, and if he could use it in conjunction with his excellent swordsmanship to suppress him and force him into a defensive posture.
But then Aokiji shook his head self-deprecatingly. He hadn't taught Yoriichi Observation Haki, and he knew that Yoriichi, who had only just learned the Six Powers of the Navy, couldn't possibly have mastered Observation Haki.
What Aokiji didn't know was that while Yoriichi hadn't learned Observation Haki, he possessed the Transparent World!
The changes in Aokiji's muscles when switching from defense to offense couldn't escape Yoriichi's notice. If Observation Haki uses "sensory perception" to predict an opponent's attack, then Yoriichi's Transparent World allows him to predict an opponent's attack by "seeing" changes in their muscles. This difference is like the difference between the Kagura Mind's Eye of the Uzumaki clan and the Byakugan of the Hyuga clan in the Naruto world.
The commotion caused by Yoriichi and Aokiji's sparring finally attracted the attention of the Marines on the warship.
The warship's course was now set, and apart from the Marines in the engine room, bridge, and watchtower, the rest of the Marines were relatively uninvolved. Those who had been loitering and chatting on the warship noticed the battle on the deck.
Word spread quickly, and soon a group of Marines surrounded the deck, pointing and commenting on the fight between Aokiji and Yoriichi.
"Oh! That red-haired brat looks familiar, isn't he the kid from Dragon's Roar Island?"
"The guy Vice Admiral Garp brought aboard, I remember now, Yoriichi Tsugikuni! Wasn't he at headquarters? How did he get on board?"
"You don't know? Vice Admiral Garp brought him aboard when we set sail. I heard he's now Admiral Zephyr's apprentice."
"Oh! Zephyr's apprentice? But he's way too strong! He wasn't this powerful when he was clearing out pirates in the East Blue, was he? He can even fight Captain Kuzan?"
The surrounding marines' discussions reached Yoriichi and Aokiji's ears, but the two, engrossed in their battle, ignored the chatter and focused intently on their opponent.
Many people on Garp's ship had seen Yoriichi before, after all, he himself had traveled to the Marines on this ship.
Some marines had even fought alongside Yoriichi.
These marines were surprised to find that Yoriichi's strength was now much greater than it had been in the East Blue. His use of the "Shave" technique in battle was highly proficient, and his elusive movements combined with his excellent swordsmanship had led to a geometric increase in his combat power.
Yoriichi knew very well that while his spiritual power might not have increased, his combat ability had improved significantly. He could probably defeat his former self within five moves.
Who said Kaido was the greatest teacher in the entire pirate world? If you ask Yoriichi, Aokiji isn't that much worse!
"Hah!" On the deck, Aokiji finally found an opening in Yoriichi's attack, deflecting Yoriichi's bamboo sword with a "popsicle" and stabbing him in the abdomen.
Yoriichi was still young, and his stamina couldn't match that of the grown man Aokiji. After
fighting for a long time, his stamina began to wane, and the frequent use of "Shave" while maintaining "Total Concentration" was rapidly depleting his energy.
Yoriichi was starting to tire and his speed was slowing down, giving Aokiji an opportunity to counterattack.
"Iron Body!"
Seeing that he couldn't dodge the ice spike Aokiji was thrusting at him, Yoriichi mentally cried out, intending to use Iron Body to block it. However, just as the ice spike was about to hit him, Yoriichi felt a tremendous force in his abdomen, sending him flying.
"Thump!!!"
Yoriichi's body flew rapidly, traveling several meters before crashing into the mast of the warship. Upon landing, Yoriichi felt dizzy and vomited, becoming another victim of Iron Body.
"Hey, are you alright?" Aokiji rushed over, asking with concern. Having been pinned down by Yoriichi for so long, he hadn't held back when the opportunity suddenly presented itself. Seeing Yoriichi's strong reaction, he was also worried.
"Huh~ I'm not hurt!"
"Iron Body is amazing!"
After a long while, Yoriichi finally recovered and stood up unsteadily. When he moved his body, he was surprised to find that he wasn't injured at all. In the past, he probably would have been rendered unable to fight by now.
"Heh!"
"Bogart, starting tomorrow, you teach him Haki."
"The Six Powers... there's no need to continue practicing them."
"He's already mastered them."
On the watchtower, Garp saw Yoriichi stand up so quickly, chuckled, and said to his adjutant before turning and leaving the watchtower.