"Are you sure that's all?"
In the forest, Naruto looked at Goku suspiciously.
If he couldn't feel Goku's sincerity, he might have thought Goku was messing with him.
"That's definitely all for sure this time."
Goku said with a serious face.
To be honest, he had never really taught anyone how to sense the Ki within their own bodies.
Whether it was his son Gohan, his granddaughter Pan, or Uub, whom he carefully trained.
They all sensed Ki on their own.
At most, he taught them some methods for using Ki and fighting techniques.
"Alright, I'll try again then."
After confirming, Naruto closed his eyes and began searching for the hidden energy within his body that Goku mentioned.
After a long while, he opened his eyes and said excitedly,
"Is it this?"
As he spoke, some light blue Chakra appeared in his palm.
"Hmm..."
Goku leaned forward, bringing his head closer to examine the Chakra in Naruto's hand carefully.
A moment later, he pinched his chin, his expression a bit strange.
"It looks similar, but it probably isn't."
This energy looked similar to Ki at first glance, but in his perception, it was still somewhat different from Ki.
As for what exactly was different, he wasn't sure either.
"Huh? It's not?"
Hearing Goku's denial, Naruto was confused.
"But this is the energy I sensed inside my body."
"Is that so... Hahaha, then I don't really understand."
Goku laughed and scratched his head, looking troubled.
Then, he suddenly remembered what Shenron said about other worlds having their own unique training systems.
His eyes lit up.
'Could it be because of this?'
'If that's the case, then it means they have both Ki and this unique energy inside their bodies.'
He felt a sudden clarity and told Naruto this.
"You're saying I have two types of energy inside my body?"
Naruto's face scrunched up, feeling a headache coming on.
"This is so troublesome! Why are there two types of energy inside me?"
"In that case, which one should I train?"
He crossed his arms, closed his eyes, and fell into deep thought.
After a while, as if he had figured something out, he opened his eyes and declared firmly,
"I've decided! I still want to train Ki!"
Because he often slept in class, he didn't know that Chakra training was their orthodox training method.
Coupled with having witnessed the power of 'Ki' earlier, he still decided to pursue Ki training.
After making his decision, he clapped his hands together forcefully and made a goal declaration.
"Within 15 minutes, I will sense Ki!"
With that, he closed his eyes, ready to continue searching for the Ki hidden within his body.
But then, Goku suddenly placed his hand on Naruto's head, holding it for a few seconds before letting go.
"???"
He looked at Goku with confusion, but Goku just smiled: "It's nothing, continue."
So he began searching for Ki again.
What he didn't know was that the reason Goku placed his hand on his head was because Shenron had just told Goku: Due to different world rules, beings in other worlds cannot autonomously sense the Ki hidden within their own bodies. To be able to sense it, they need its help.
Meanwhile, after giving a few instructions to Sasuke and Sakura, Kakashi followed the traces left by Naruto and Goku.
Although he could temporarily determine that Goku meant them no harm and even held significant goodwill towards them, Goku's appearance was too sudden, and his identity and origins were mysterious, so he remained cautious.
After seeing Naruto pull the other person outside, he secretly followed them.
On one hand, he wanted to see why Naruto had taken the other person out.
On the other hand, it was to protect Naruto.
After all, Naruto was not only his student but also the Jinchuriki of the Nine-Tails, and the only child of his teacher.
In the past, due to his own decadence and degeneration, he failed to properly care for his teacher's child.
Now that he had taken his teacher's child as his student, he should make up for the neglect of all these years.
"Hmm? What are they doing?"
He quickly followed the traces to a spot not far from Naruto and Goku, hiding in a large tree and turning his gaze towards the two.
He immediately saw the two of them sitting cross-legged on the ground.
"What are they doing?"
His mind was full of questions, but he didn't reveal himself, continuing to observe quietly.
Over the next period of time, he successively saw Naruto jumping up in frustration, sitting back down, and producing Chakra in his hand.
Then, after Goku said something, Naruto shouted that he would train Ki.
"Ki?"
Hearing this word again, Kakashi felt puzzled.
'What exactly is Ki?'
'And what is this Ki training Naruto mentioned?'
15 minutes passed.
Half an hour passed.
Another half an hour passed...
In the clearing, Naruto opened his eyes, gritting his teeth in frustration.
"Damn it! Why can't I sense it?"
For the past hour, he had been searching for the Ki within his body but couldn't find it.
Given his impatient nature, being able to persist this long in one go was already his limit.
So he couldn't help but pause his training now.
"You can't rush this."
Across from him, Goku, who had also been sitting cross-legged the whole time, looked at him and said.
"Back in my day, it took me quite a while to succeed."
"Hmm, is that so?"
Naruto scrunched up his face, then thought about why he was doing all this and took a deep breath.
"Alright! I won't give up!"
"I'm the man who's going to be Hokage! How can I let something small like this defeat me!"
With that, he closed his eyes again, calming his mind to continue sensing his Ki.
Time passed bit by bit.
Soon, two hours had passed.
Kakashi, who had been hiding in the tree the whole time, felt his legs go numb from squatting. He glanced with his dead-fish eye at the gradually setting sun, feeling very helpless.
'What exactly is Naruto doing?'
'And what am I doing?'
'Wasting so much time here watching the two of them meditate?'
After all, Zabuza could attack again at any moment, and right now, only Sasuke and Sakura, along with the shadow clone he left behind, were in the village.
Although the shadow clone had a certain level of strength and could buy some time if they encountered Zabuza, waiting for his real body to return, there was still a certain level of risk.
What if he couldn't make it in time?
Thinking this, he decided to reveal himself and take Naruto back, lest any changes occur as dusk approached.
But just as he stood up, before he could jump into the clearing,
A loud, excited voice suddenly rang out.
"I FELT IT!!"
In the clearing, Naruto, who had been sitting for a long time, suddenly opened his eyes and stared intently at his palm.
A wisp of faint white gas suddenly rose from his palm, swirling above it.
"Goku, look! Is this it?"
Naruto quickly brought his hand close to Goku, asking anxiously.
Through his persistence and effort, he had finally discovered this energy within his body.
Although his intuition told him this was Ki, he didn't dare confirm it himself and wanted Goku to judge.
Whoosh~~
However, before Goku could confirm, the Ki in his palm dissipated because his concentration wavered.
"Huh? Where did it go?"
Seeing the Ki disappear, he scratched his face frantically.
"You need to keep your mind focused to guide it out."
Seeing this, Goku reminded him.
Hearing Goku's reminder, Naruto calmed down, then closed his eyes and tried again.
A few seconds later, Ki once again appeared, swirling around his hand.
This time, he tried his best to maintain the Ki's presence, carefully extending his hand towards Goku.
"That's right, this is Ki."
After a brief perception, Goku confirmed that the energy Naruto had guided out this time was indeed Ki.
"I succeeded?"
Hearing Goku's confirmation, Naruto stared blankly at his palm.
As he lost focus, the Ki disappeared once again.
But this time, he didn't get frantic. Instead, he suddenly jumped three feet high.
"I SUCCEEDED! HAHAHAHA!!"
After jumping up, he put his hands on his hips and laughed triumphantly.
And just as he was laughing heartily, a figure suddenly landed in front of him.
It was Kakashi, who had been hiding in the tree for a long time.
"Yo! You finally came down."
Seeing Kakashi, Goku waved and smiled.
Hearing Goku's greeting, Kakashi stumbled, looking at Goku in disbelief.
"You knew I was there all along?"
"Yep."
". . . Since when?"
"Since you arrived."
". . ."
Kakashi was speechless.
'So why did I squat in that tree for three hours anyway?!!!'
(A/N: In this book, Shenron is a supreme existence relative to other worlds, so it can easily send Goku to travel to other worlds and can lift certain restrictions, giving people in other worlds a chance to sense the Ki hidden within their bodies [the restrictions refer to the fact that due to different world rules, beings in other worlds have Ki within them but cannot sense it on their own]. This explains the bug of why no one in the other world could sense Ki before Goku arrived.)
(Also, although they cannot sense the Ki hidden within their bodies, if Ki manifests energy fluctuations externally, people from other worlds can feel it, but most would mistake it for Chakra because its fluctuations are close to Chakra fluctuations.)
(Finally, as for why Shenron is so powerful, let's just say that's the setting of this book.)