After resolving the small misunderstanding between the two sides, Naruto Uzumaki continued baring his teeth in pain under Nagato's supervision, using the Gedo Statue to restore the chakra the nine Tailed Beasts had lent him into its purest chakra state. Then, he tried to use that chakra, which carried no spirit or information, to awaken the Nine-Tails within his body.
As for Sasuke Uchiha, he followed behind Orochimaru with an unwilling expression, undergoing examinations so Orochimaru could custom-build a prosthetic arm capable of restoring his full combat strength.
"Don't look so guarded and nervous, Sasuke-kun… You're making it seem as if I really would eat you."
Orochimaru could not suppress the smile on his face as he drew Sasuke Uchiha's blood. Then he bent down and began measuring various data around Sasuke's severed arm, speaking in a light tone.
"Wouldn't you, Orochimaru?"
Sasuke frowned, unused to having someone touch the cut surface of his left arm, but he restrained his emotions and asked back as calmly as possible.
"Hm. It seems that in your world, 'I' left you with quite an awful impression…"
Orochimaru lightly shook the blood collection vial containing Sasuke Uchiha's blood. Then, completely unconcerned with the strange looks around him, he extended his tongue and licked the blood-drawing needle before continuing with a sinister smile.
"But judging by your earlier reactions, the relationship between us was not purely terrible… Can you still recall how it felt when you activated the Curse Mark of Heaven, Sasuke-kun?"
"That thing was buried long ago, together with your ambition to devour me, by Itachi and me."
Sasuke Uchiha looked coldly at Orochimaru, whose gaze had landed on the side of his neck.
"Besides, the so-called Curse Mark was nothing more than a crude imitation of senjutsu. Even the Curse Mark of Heaven cannot compare to true Sage Mode… Why bring it up now?"
"You are right. Even the Curse Mark of Heaven is only a degraded version of Sage Mode."
Orochimaru smiled with amusement. He placed Sasuke Uchiha's blood onto a nearby test tube rack, then activated a petri dish cultivating Hashirama cells while asking in a meaningful tone,
"But is that truly the only value it possesses, Sasuke-kun?"
"What are you trying to say?"
Sasuke Uchiha frowned deeply. Inevitably, he recalled the scene where he had used Orochimaru's flesh from Anko Mitarashi's Curse Mark of Heaven to revive Orochimaru, who should have been sealed away forever by Itachi, body and soul destroyed.
"You have seen the Otsutsuki clan's shinobi. Don't you think that the forbidden technique known as the Curse Mark of Heaven has already touched part of their mystery?"
Orochimaru turned his head and asked, his gaze sharp and proud.
"…Karma?"
Hearing Sasuke Uchiha utter that word in an incomparably grave tone after a moment of silence, Orochimaru licked his cheek with great pleasure and muttered to himself with a sinister smile,
"Ever since Rei-kun revealed to me that the Otsutsuki clan can, even after their bodies are destroyed, transform their own information and chakra into a special form of existence called Karma, then continuously reincarnate and revive, I have been thinking about the difference between that Karma, which can carry all of their information and power, and my Curse Mark of Heaven…"
"Is the difference in the level of power? Or is it in the selection of reincarnation vessels? I thought about it for a very long time. I even had Rei-kun, who had personally carried Kaguya Otsutsuki's Karma, observe the entire process while I reincarnated myself into this current artificial body, hoping to find the difference between these two techniques."
"But the answer Rei-kun gave me was that there is no fundamental difference… Ah, can you understand the surprise and full-body tremor I felt at that moment, Sasuke-kun?"
Sasuke Uchiha drew in a soft breath.
At last, for the first time in many years, he looked at Orochimaru before him with an incomparably solemn, serious, and even somewhat admiring gaze.
Orochimaru, who achieved resurrection through his own flesh and the Curse Mark of Heaven planted on a chosen vessel.
The Otsutsuki clan members, who used the Karma formula to completely record their own information and chakra, then slowly decompress, awaken, take over, and revive within a qualified vessel.
Was there truly any fundamental difference between them?
No.
Both were lives revived from the chakra information recorded inside the Curse Mark of Heaven or Karma.
Or rather, both had transformed their own life form, through special means, into "information" lodged within chakra.
As long as the chakra belonging to them continued, their "life" would not end.
As long as that information could find another vessel capable of carrying it, they would forever be able to descend into the world again from that information.
"What exactly… have you turned yourself into, Orochimaru?"
"Instead of asking me that question, you would be better off thinking carefully. For those Otsutsuki who can cross the stars and use the Karma technique to achieve eternal life, what is truly important? Is it the Chakra Fruit, which gathers the chakra of all living beings upon the earth, or is it the information belonging to that planet, recorded within that chakra?"
Orochimaru entered the data he had just measured into the petri dish containing Hashirama cells. Then he injected part of Sasuke Uchiha's blood into the dish before smiling wickedly at him.
"Excluding Kaguya Otsutsuki, who originally existed as Isshiki Otsutsuki's guardian and sacrifice, at least Isshiki and Momoshiki, two members of the Otsutsuki clan, should have both consumed Chakra Fruits before… But in their battles against you, did they truly display power that far surpassed Kaguya Otsutsuki on a higher level?"
"Most likely not… Otherwise, judging from the fact that even an incomparably weakened Kaguya Otsutsuki possessed enough power to easily tear the moon apart, Isshiki and Momoshiki, who should be on a different level from her and in more complete states, ought to possess the strength to completely destroy the entire shinobi world in a short time. And that kind of strength is obviously not something that you and Naruto Uzumaki, two people whose strength had stagnated for a long time, could resist."
"Then, since the Chakra Fruit did not grant the Otsutsuki clan a leap in absolute power, its true meaning most likely leans more toward the planetary information capable of allowing their life level to transform further."
"And if what is truly important is information… then the Curse Mark of Heaven, which can likewise transmit information and achieve resurrection, possesses a value countless times more important than merely increasing combat power… What do you think, Sasuke-kun?"
Sasuke Uchiha said nothing.
He only looked at Orochimaru before him, who had spread his arms as if describing some beautiful dream.
After many years, a sense of fear toward this man once again emerged in his heart.
With Rei Kaguya indulging you almost unconditionally…
Just what kind of monster have you become, Orochimaru?