Time flew by in the blink of an eye.
Before he knew it, the moon was already high overhead.
"Ah!"
Kimura Takuya had just dispelled his Shadow Clones, and the memories and experience they'd accumulated over half the night flooded into him.
The pain made him cry out.
"These are only a dozen or so clones. How does that kid Naruto handle so many?"
Could it be because Naruto was simply too thick-skinned to care?
Or was it because of the nature of his soul?
A heightened ability in some area could be an advantage, but it might also become a weakness.
Take a dog's sense of smell, for example. It could detect incredibly faint scents, but unpleasant odors affected it all the more strongly.
His own soul had heightened spiritual perception, which also made him more sensitive to the fatigue of his soul.
Sure enough, everything had its pros and cons.
"Phew. I'm done absorbing the memories. Now it's time to practice Senjutsu Chakra again."
Kimura Takuya let out a long breath and went to the room he used for cultivation in the base.
The room was completely sealed, so no one would come in and disturb him.
Kimura Takuya sat cross-legged in the middle. The room was close to the ground.
The forest lay just above the ceiling, and thick tree roots surrounded the room on every side.
He'd chosen this spot because he'd discovered that the enormous trees in the forest could absorb Natural Energy, too.
Their roots were where Natural Energy gathered most densely, making this an ideal place to practice Sage Mode.
Kimura Takuya could have used the Reverse Summoning Jutsu to visit Shikkotsu Forest.
But he was afraid that learning the forest's Senjutsu might skew his understanding and make it harder to develop his own Sage Mode.
So he decided to first extract Senjutsu Chakra on his own, then visit Shikkotsu Forest to seek the Slug Sage's guidance.
Kimura Takuya had already tested a one-to-one-to-one ratio. The energies couldn't balance at all, let alone be refined into Chakra.
To achieve balance among the three, he first had to quantify all three types of energy using a common unit. But their natures were completely different.
The one-to-one-to-one ratio he'd tried before was like comparing a cubic meter of iron with a cubic meter of water. They looked the same size, but their weight and density were completely different.
So the idea of balancing the three energies that way made no sense.
He had to determine how many units of physical energy and Natural Energy corresponded to one unit of spiritual energy.
Only then could he truly balance the three.
To do that, he needed a standard measure that could accurately quantify all three energies.
This standard measure had to meet four requirements.
First, it had to be immutable—in other words, stable enough to be quantified.
Second, it had to be readily available in sufficient quantities to meet experimental needs.
Third, it had to interact with all three types of energy: spiritual, physical, and Natural Energy. In other words, all three had to be able to act upon it.
Fourth, it had to be highly sensitive to energy, so it could precisely measure different types.
Taking all of this into account, Kimura Takuya found something perfectly suited to the task.
It was practically made to serve as a standard measure of energy.
Cells!
Any cell could be influenced by all three types of energy.
And when a cell divided, the new cells were identical to the original.
They were also easy to obtain.
Cells met every requirement for an energy standard!
After choosing his standard measure, Kimura Takuya selected the most stable and energy-sensitive cells he could find: Hashirama Cells.
Hashirama's cells had extraordinary stability and sensitivity to energy. They also multiplied incredibly quickly in a laboratory.
Kimura Takuya had once taken just a tiny sample from Danzo's right arm. In less than two days, the cells had nearly overflowed their petri dish.
Kimura Takuya then used his different types of energy to stimulate the cells and measure their rate of division.
He found that one unit of his spiritual energy could make a single First Hokage Cell divide into 1,987 cells.
One unit of physical energy, however, could only make a single First Hokage Cell divide into fifteen.
And one unit of Natural Energy could make a First Hokage Cell divide into 382 cells.
In other words, the ratio he'd tried before wasn't one-to-one-to-one.
It was 1,987:15:382.
No wonder the energies had been impossible to balance.
If he used the largest number as the standard unit, the true ratio would be:
1:132:5—that is, one unit of spiritual energy corresponded to 132 units of physical energy and five units of Natural Energy.
And 132 and 5 both had decimals that went on forever.
Those differences in the decimal places were probably what accounted for the variations among the Sage Modes of the great sage regions.
No one could guarantee that their energy levels had the same ratios as anyone else's. Only the standard for Natural Energy was fixed at 382 cells.
Everyone else's values differed, so the ratios they calculated also differed in the decimal places. That explained the differences in precision among the great sage regions.
For Kimura Takuya, one unit of spiritual energy was equivalent to 1,987 cells, while one unit of physical energy was equivalent to fifteen.
Everyone else's figures were bound to be different.
That was why not every creature in the Three Great Sage Regions could learn Sage Mode.
After determining his own energy ratios, Kimura Takuya had spent several days testing them.
He was mainly testing the values in the decimal places and had now reached the sixth decimal place.
Tonight, he was testing the seventh.
Even with his level of control, handling energy with that degree of precision was becoming difficult.
That was why ordinary people could never learn Sage Mode. Even if they got lucky once, they'd never manage to do it again.
Those naturally gifted in Sage Mode probably had spiritual and physical energy levels that were both close to 382 cells—the amount corresponding to one unit of Natural Energy.
They only needed to make a few slight adjustments to learn it.
Naruto and Kabuto were like that.
Jiraiya might have been a little less gifted, but he was still far better than most people.
Hashirama was probably a freak whose energy levels were all nearly 382:382:382. Only such a perfect ratio could let him use Sage Mode without any restrictions.
That was the secret behind Hashirama's ability to use Sage Mode at will.
And if Hashirama hadn't learned Sage Mode from Shikkotsu Forest, but had figured it out on his own, he would have achieved the most perfect Sage Mode of all.
Kimura Takuya stopped musing and focused. Carefully, he drew the three types of energy together at his fingertip, concentrating on controlling their ratio.
He was ready to cut off his finger at a moment's notice.
In fact, seven or eight fingers already littered the ground. Every one of them had turned to stone, like a fossil.
Still, at least they hadn't transformed into something else. That meant he was on the right track and that this truly was a perfect Sage Mode for humans.
"I did it! Hm? Slash!"
He'd just managed to combine the energies into Senjutsu Chakra, and excitement made him lose focus. The result was another failure.
The instant his finger turned to stone, Kimura Takuya cut it off.
His finger regenerated in the blink of an eye. Kimura Takuya murmured to himself.
"I got careless, but I can already call this a success. I can do it if I'm precise to the seventh decimal place.
"But it's not stable enough yet. The moment I lose focus, it becomes hard to control. To achieve perfect control, I estimate I'll have to get precise to the tenth decimal place.
"Is this the limit of ordinary people?
"Even if someone knows the method and the ratio, who can control it to this degree?"
Kimura Takuya sighed, then immediately started experimenting again.
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