The reason for originally planning to stay on this island for two days was simple.
Because that's how long it takes for the tailor to finish her work.
As an ordinary person without any special abilities, being able to custom-make clothing based on a client's measurements in just two days, even if the design wasn't particularly complex, was already impressively efficient.
It just goes to show that those who dare to open a tailor shop in the Grand Line definitely have some real skills.
Back at the same clearing as before.
"There are many issues with your current abilities, and it's unrealistic to expect them all to be resolved in a short time."
After all, Ace is not that kind of tsundere character.
After being thoroughly convinced by Naruto's reasoning, he finally admitted his own shortcomings.
"Your Devil Fruit abilities aren't developed enough."
As he spoke, Naruto decided to demonstrate, forming hand seals.
Then, under Ace's stunned gaze, he spat out a massive fireball.
The tree struck by the fireball instantly burst into flames.
"The most basic form of flame-based attacks is burning, but don't forget… high temperatures are also a means of offense."
As he said this, he increased his Chakra Output, causing the range and temperature of the Great Fireball Technique to rise sharply.
The surrounding air grew scorching hot, and the light even began to distort slightly.
Even as a user of the Mera Mera no Mi, Ace, when not actively using his abilities, felt the heat of flames just like any ordinary person.
"Even superheated air, when inhaled into the lungs, can cause severe damage. Don't limit yourself to just direct attacks."
After saying this, Naruto turned around to see Ace staring at him, dumbfounded.
"Hey, snap out of it."
Ace, who had just been flicked on the forehead, quickly came back to his senses and looked at Naruto in disbelief.
"Uncle Naruto, that ability you just used…"
He hesitated to speak.
'Is Naruto also a Devil Fruit user?'
"That? That's ninjutsu. There are plenty of people on the seas who can use similar abilities."
Among the people Naruto knew alone, there were quite a few who could unleash powerful flame-based attacks.
"Don't think only Devil Fruits can achieve this kind of effect… did you remember everything I just said?"
Seeing Naruto raise his fist, Ace instinctively covered his head and nodded.
"Good, then I'll continue."
"Don't over-rely on your Devil Fruit abilities. Haki is the foundation of combat between true powerhouses."
"If you only focus on your Devil Fruit's power while neglecting Haki training, enemies will easily exploit your weaknesses."
"Your body can turn into flames, so you need to get used to integrating Haki into your attacks."
Even seemingly intangible flames can be imbued with Haki.
Doing so might not increase the temperature of the flames, but it would enhance their destructive power.
As he explained, Naruto started to wonder whether he could incorporate Haki into his Ninjutsu.
'For example, a Wind Release: Rasengan infused with Conqueror's Haki?'
'I'd have to try it next time.'
"Also, don't get careless just because you're a Logia user."
He reached out and flicked Ace's forehead again. Ace tried to dodge, but it was futile.
"Train yourself to use Observation Haki instead of just your 'vision' to track enemy attacks."
"Like I said earlier, since elemental intangibility can be countered by Haki, you can proactively disperse parts of your body when you predict an incoming strike."
As he spoke, he casually swiped at Ace's head again.
Ace immediately applied what he'd just learned, turning his head into flames to avoid the hit.
"Just like that. It's seems you're not completely hopeless."
After saying this, Naruto took off his coat and stretched his limbs.
Alright, the basics are covered. The advanced applications of Armament Haki and the techniques of Conqueror's Haki Infusion aren't things you can master overnight."
"Once you return to Whitebeard's ship, have him teach you… assuming he hasn't gotten too old to move."
After hearing this, Ace immediately opened his mouth to retort, but a sharp glare from Naruto shut him up.
Well, maybe not completely… He still muttered under his breath after turning away, something along the lines of 'Pops is the strongest'.
'Sigh. This kid never grows up.'
Naruto shook his head in exasperation before turning serious again.
"Enough talk. None of this matters without practical training."
"Come on!"
As he spoke, Naruto's body once again radiated Haki.
"Don't worry. Even if you get hurt, I'll patch you up."
Ninjutsu is truly awe-inspiring.
What followed was a brutal, merciless training session.
Even after Naruto had pointed out his flaws, the gap between Ace and him remained vast.
Still, compared to his earlier sloppy performance, Ace had improved significantly.
'Guess the kid really did inherit his father's combat talent.'
'That old Whitebeard, he is really delaying his child's growth!'
With that thought, Naruto increased the intensity of his attacks by another notch.
Another day passed quickly.
Naruto's new clothes were finished, and it was time to part ways.
After healing Ace, who was once again lying on the ground, panting and bruised, Naruto withdrew his hand.
"Not bad. You've got real talent."
The 'talented' Ace just rolled his eyes at Naruto.
"Why does it sound so awkward to hear you say this?"
"Alright, it's time for you to get back to your own mission."
As he said this, Naruto took a deep look at the boy, whose birth he had witnessed, and suddenly said in a solemn tone, "One last piece of advice."
"If you realize you've walked into a trap, don't stubbornly fight to the death."
"In that kind of situation, running away isn't shameful."
,
Ace clearly disagreed with this. He wanted to open his mouth to argue, but was interrupted by Naruto's next words.
"Think about the people you love… and those who love you. How would they feel if you died in some enemy's hands?"
Ace fell silent after hearing this.
In the end, Ace still left. Whether or not he truly took Naruto's words to heart, no one could say.
However, as Naruto watched him speed away on his flame-powered jet ski, a thought crossed his mind.
'What a good thing!'
Recalling his own past experiences, Naruto started considering the idea of getting himself a custom-made vessel.
It couldn't be helped.
Sea Kings weren't something he could just stumble upon whenever you wanted, and regular ships were too slow.
With that in mind, Naruto had already decided on his next destination.
The nearest shipbuilding island, Water 7, which is also conveniently on the way.
'It is said that Captain Roger's Oro Jackson was built there. Surely crafting a single-person vessel powered by wind or some other energy source wouldn't be too difficult, right?'
Sharpening the axe won't delay the cutting of firewood.
'There was still a long way to the New World, so this time, I'll just take the route through Sabaody Archipelago.'
'Come to think of it, it had been a while since I last saw Uncle Rayleigh.'