Kaguya wasn't exactly wrong.
With her power, she could do it.
Permanently suppress the natives of this world.
Pen them in; if they don't refine chakra, kill them. Over time, no one would dare resist.
But it was still risky.
For example, the Three Great Holy Lands—and her two sons.
Besides, this approach wouldn't showcase Natsume's cleverness.
So he wouldn't agree.
"I have a way to make them willingly offer their chakra—and make them your most loyal soldiers."
"...?"
For once, Kaguya showed a clear expression change.
Because she simply didn't believe such a thing existed.
She lacked common sense, not brains.
Unless she cast Infinite Tsukuyomi, she couldn't think of a second method.
Infinite Tsukuyomi is when the owner of the Rinne Sharingan projects their eye power onto the moon, plunging the whole world into illusion, and the God Tree wraps and absorbs everyone's chakra to gestate a new fruit.
If not dispelled in time, the wrapped people become White Zetsu, leading to the world's end.
What Natsume described was, in essence, Infinite Tsukuyomi.
And making people voluntarily offer their chakra and lives.
Unbelievable.
"What method?"
Even an ascetic like Kaguya felt strong curiosity.
"I call it the Skynet."
Natsume kept it simple. "Use the God Tree as the hub, link people via chakra, and form a vast net."
Basically the internet—no, an MMORPG.
"Go on."
Kaguya watched him, maintaining her cool demeanor.
In fact, she didn't understand.
But she couldn't ask a servant.
That would make her seem incompetent—and embolden the servant, eroding proper awe.
"Once the Net is woven, chakra can be used as currency."
Natsume paused. "For instance, if someone wants to learn a certain ninjutsu, they must pay a set amount of chakra."
"What is ninjutsu?"
Kaguya more or less understood a bit.
But she couldn't grasp "ninjutsu."
In her concept, there was no such thing.
Her "ninjutsu" were instinctive innate abilities—
Like Amenominaka, or All-Killing Ash Bones.
Those aren't really ninjutsu, since they can't be learned.
"It's how one uses chakra."
Natsume shamelessly said, "Because I don't have as much chakra as you, I developed a system called ninjutsu."
Right now, the Sage of Six Paths was still a little kid.
No problem claiming this.
And theoretically, it wouldn't affect the future.
Whoever owns the naming rights, chakra and ninjutsu would spread regardless.
"Please look."
Natsume formed hand seals. "Water Style: Water Whip."
Soon, a whip of water appeared in his hand.
Kaguya fell silent.
Chakra had attributes.
That she knew.
And she had all attributes.
For that reason, she never bothered to break it down; instead, she used Truth-Seeking Orbs with Yin-Yang and all five elements.
One force to break ten thousand techniques.
But she had to admit, Natsume was very clever.
For the first time, Kaguya felt this servant possessed great wisdom.
This system wouldn't be easy to invent even for her.
But she could do it.
Kaguya formed hand seals; a water whip appeared.
"Meaningless."
She felt its strength and shook her head.
"For you, yes. But for ordinary humans, it's very useful."
Natsume thought physical arts would help Kaguya most. "With ninjutsu, they'll willingly offer chakra. And think—if killing an enemy grants higher-level ninjutsu as a reward, what will they do?"
Kaguya considered, and her eyes brightened slightly.
Interesting.
They would strive to grow stronger—becoming her most loyal warriors.
"You can resurrect ordinary humans, yes?"
Natsume asked.
Kaguya nodded.
Unlike Rinne Rebirth, which trades life for life, her level was higher; she could revive a human at very small cost.
"Then make resurrection a reward."
Natsume's lips curved. "Do you think they'd go mad for it?"
If you can revive, what's there to fear?
Kaguya stared at him, momentarily at a loss for words.
If the Ōtsutsuki had known this method before, perhaps there wouldn't have been so many rebels.
Sometimes, some even fell due to that.
There were too many planets; there would always be one or two Children of Fate.
"What do you think?"
Natsume asked when she didn't reply.
As for deities, they'd be easier.
Without faith, they'd either surrender or be swept away by Kaguya and the players.
Only question was how the Three Great Holy Lands would react.
On the surface, Natsume's method benefited the world.
If enough people joined, perhaps the God Tree wouldn't need to drain the planet's energy.
But the lofty Holy Lands would lose status.
The Slug Sage might not mind by temperament.
The other two were less certain.
Especially the Great Toad Sage, who was clearly ambitious.
On that note, Natsume rubbed his chin, pondering a question.
Could he still summon the Slug?
Probably not.
After all, summoning contracts like that hadn't appeared yet.
"We'll do as you say."
Kaguya nodded.
Achieving Infinite Tsukuyomi's effect without casting it—why refuse?
Casting Infinite Tsukuyomi cost energy too.
And she could distinguish whether ordinary humans or shinobi provided more chakra.
Kaguya looked at him, thoughtful.
Perhaps she should give him a reward?
His proposal was outstanding.
Given his wisdom, she'd likely need him again.
Thinking so, she asked, "Do you have a request? I can grant it."
Natsume was slightly stunned.
Well now!
So Kaguya wasn't completely clueless.
What should he ask for?
Something too excessive would be impossible.
Like having her help evolve his Sharingan to Rinnegan.
Given her obsession with chakra, no way.
Natsume thought of another.
Have her create ninjutsu.
With her power and talent, she wouldn't be inferior to the Sage of Six Paths.
She didn't use ninjutsu only because she didn't need to.
But ultimately, he thought of something else.
A reward is momentary; if he could win over the person, that would be a real windfall.
He looked at Kaguya, gradually closing in.
In the end, they were pressed together.
Kaguya stared at him and didn't dodge.
Because she had no concept of romance or relationships.
More importantly, she didn't dislike Natsume.
So yes—looks matter.
Natsume looked at her calm, exquisite face, and finally at her pale-red lips.
He gently kissed her.
"...?"
Puzzlement showed in Kaguya's eyes.
What was this?
Unexpectedly, she didn't dislike it.
A feeling she'd never experienced slowly spread.
"This is the reward."
Natsume bluffed. "For me, it is. Not for others. After all, as a servant, the most precious reward is contact with the master."
Preferably at zero distance.
Kaguya showed a hint of relief.
It sounded reasonable.
Though this servant was odd, the results benefited her.
And it cost no chakra; simple physical contact was enough.
Nothing too serious about it.
"There's one important precondition for the Skynet."
Natsume licked his lips and continued, "Goddess, do you have a way—say, using the God Tree as a center—to develop a ninjutsu that converts chakra into thought-waves, allowing communication over any distance?"
He was basically describing the Akatsuki's Magic Lantern Body Technique.
If the Rinnegan could do it, the Rinne Sharingan certainly could.
Kaguya thought briefly and nodded.
She hadn't created ninjutsu before, but her level was what it was.
Bottom-up is hard; top-down is easier.
"It'd be best to bind it to an object—say a bracelet or ring."
Natsume added.
If it were purely a ninjutsu, it'd be fussy.
Like Akatsuki—use rings.
More precisely, a game login device.
Through the God Tree, turn this world into an MMO.
In a sense, indeed Infinite Tsukuyomi.
"Mm."
Kaguya stopped speaking and pondered.
Natsume didn't interrupt.
He needed to select the first batch of beta testers.
Even in later ages, when chakra was widespread, many still lacked talent as shinobi.
In this era, even more so.
Naturally, Natsume had to pick high-level players—those with talent.
That would also spare Kaguya a lot of trouble.
Come to think of it, he was a very dutiful servant.
Natsume immediately summoned the soldiers of the Land of Ancestors to assemble.
They were called soldiers, but most were ordinary people.
Only the samurai were elite.
…
Meanwhile, at Mount Myōboku.
The three current great sages gathered.
"Gamamaru, how goes it?"
The White Snake Sage asked around its pipe.
It was very young then and hadn't taken human form.
But in strength, it was already a standout of Ryūchi Cave.
"I've arranged for humans to bestow Ōtsutsuki Kaguya with blessings of fertility."
Gamamaru, the future Great Toad Sage: "It won't be long before her children are born."
"Are you certain?"
The White Snake Sage asked worriedly. "Though affected by faith, she isn't human. Will they really help us fight their mother?"
"I have seen it all."
The Great Toad Sage pointed to his eyes. "Prophecy will guide them. We only need to wait."
"If only we could find the one Kaguya ambushed."
The White Snake Sage sighed. "But with his ability, he's hard to detect."
"That day will come."
The Great Toad Sage said, "With our two-pronged approach, we will defeat Kaguya and save humanity and our world."
The Slug Sage listened without chiming in.
Unlike Mount Myōboku and Ryūchi Cave, it had always been solitary.