'I don't recall the original contents of the stone tablet, Hagoromo's true words, but I do know that this one has been altered by Black Zetsu,' Kakashi thought.
Sasuke activated his Sharingan, and the two tomoe spiraled in his crimson eyes. He read and explain the contents of the stone tablet aloud. "It has some history of a God Tree, the Sage of Six Paths, and his two sons, Indra and Ashura, and their rivalry. It also tells the tale of how those two brothers are destined to fight for power. And..."
Sasuke paused. Naruto, on his left, looked at him curiously, waiting for him to continue. Kakashi, on his right, wasn't too surprised. He had not known that the stone tablet held this tale for all Uchiha Clan members to read. But was skeptical on why Kaguya Ōtsutsuki wasn't mentioned here on upper-level of the Stone Tablet.
Sasuke turned to Kakashi and said, "The stone tablet also explains the general process for awakening the Mangekyō Sharingan!"
Naruto's blue eyes widened slightly in surprise. Over the last few days, he had gained a surface-level understanding of what the Mangekyō Sharingan truly was, from Kakashi mostly. He was shocked that if such a thing was written on this tablet, why didn't all Uchiha have the Mangekyō Sharingan? If the process was already written, why didn't they follow it and attain the Mangekyō Sharingan? He also turned to Kakashi, staring at him curiously for answers.
Under their dual gazes, Kakashi simply said, "First, Continue reading, Sasuke."
Sasuke nodded before explaining the process. "It... It says the next stage of the Sharingan's evolution, a path to ultimate power, is only attained through a deep-seated loss or trauma... the death of a close friend or loved one."
As he finished, he gasped, slowly turning his head to his left, eyeing Naruto with worry. Naruto, upon hearing this, nodded, understanding why not all Uchiha had the Mangekyō Sharingan; he thought no one would kill their loved one for power, atleast not all would choose this step.
But seeing Sasuke's worried eyes at him, he flinched. "Hey! Why are you looking at me like that?"
Sasuke shook his head. "Nothing."
Kakashi wasn't surprised by this and asked, "Sasuke, is that all you could read? And are there no drawbacks written for the Mangekyō Sharingan?"
Sasuke glanced at Kakashi with a confused look. "Drawbacks? Could even an ultimate power have drawbacks? And... no, this was all I could decipher. I don't think there's anything worthwhile ahead, anyway. But what drawbacks?"
Kakashi didn't speak for a moment, but seeing Sasuke's curious gaze, he decided to tell him. "Blindness! If you overuse the Mangekyō Sharingan's abilities, you will ultimately go blind."
"HUH!!" Hearing Kakashi, Sasuke gasped. Even Naruto was shocked; Kakashi hadn't mentioned the blindness issue with the Mangekyō Sharingan, when tell him little about it with story of Kyūbi Rebellion incident and how someone use Mangekyō on Kurama, but didn't mention Obito's name directly there.
Kakashi ignored their surprised looks and thought, 'This tablet was originally made by Hagoromo so that the descendants of Indra wouldn't try to pursue the Rinnegan and instead walk the path of true peace through cooperation.'
He scoffed internally. 'Hah, bullshit. If it were that simple, why would the world still be in such a state centuries later? Even though Madara was stupid enough to believe in an obvious Genjutsu like the Infinite Tsukuyomi, his and Sasuke's path to peace was correct in the anime. Ashura's and Naruto's path, which aligns with Hagoromo's, has already been proven wrong as an unachievable ideal throughout the years.'
Sasuke nudged him, pulling him out of his thoughts. He asked in a serious tone, "But Kakashi-sensei, how do you know about this drawback of the Mangekyō Sharingan? Are you sure there are such issues with Mangekyō Sharingan?"
Kakashi smiled, his right eye wrinkling with a glint of mischievousness. He removed his forehead protector from his left eye and opened it to reveal a three-tomoe spinning in his crimson Sharingan. But immediately, they began to spin rapidly and merged to form a three-pointed, sharp shuriken blade pattern. Naruto didn't understand, but Sasuke was immediately dazed as his memories of Itachi's Sharingan resurfaced.
He muttered, "M-Mangekyō? How?"
Kakashi chuckled, expecting this reaction when he thought of showing Sasuke his Mangekyō Sharingan, Kamui. He had been thinking of showing it to Sasuke sooner, once he reached the three-tomoe stage. Today wasn't planned, but he decided to do it anyway. It wasn't like Sasuke was going to shout it to all of Konoha.
Naruto, hearing Sasuke, asked in disbelief, "Kakashi-sensei, do you also have a Mangekyō Sharingan? Wow, that's really cool, but you won't use it on my grumpy fox, right?"
Kakashi shook his head. "No, no, I wouldn't."
Naruto sighed in relief, but in his mindspace, he heard a loud curse from Kurama, who was shouting not at the revelation of Kakashi's Mangekyō Sharingan but at Naruto for calling him a "grumpy fox."
"B-BUT! HOW CAN YOU HAVE THE MANGEKYŌ SHARINGAN? YOU AREN'T EVEN AN UCHIHA?!" Sasuke blurted out loudly, unable to believe that Kakashi, a non-Uchiha, had evolved his clan's Dōjutsu into its ultimate form.
"First, stop speaking in Capital letters! And secondly, didn't you just read that the next stage of the Sharingan evolves through the death of a loved one?" Kakashi casually replied to Sasuke's outburst. "Both of my teammates died in front of my eyes, and then my Sensei died. Why wouldn't my Sharingan evolve then? Being an Uchiha or not isn't the point here."
Sasuke was dazed again, but then he remembered that this was, in fact, written on his clan's sacred stone tablet.
He believed Kakashi's explanation and asked, "So that's why you know about this vision loss drawback of the Mangekyō and didn't use it yourself much? But does that also mean even Itachi..."
Kakashi immediately answered, "Yeah. He also feels strain whenever he uses his Mangekyō Sharingan. That's why I don't use it unless necessary, and only use its normal transformation. And that necessary need hasn't come yet."
Kakashi then glanced at the stone tablet and said, "Let me decipher the next part for you, which requires a Mangekyō to read."
Sasuke nodded, still in a state of disbelief, while Naruto was less worried about things that didn't directly concern him.
"The next thing written here is that the conflict between the Sage of Six Path's sons will be broken by a final, decisive battle." Kakashi read the ancient text and explained it to Naruto and Sasuke. "And it's also written that a ''Genjutsu'' called Infinite Tsukuyomi is the final step of salvation to achieve eternal peace in the world."
Kakashi laughed, turning to his students. "What do you two think about this? Do you believe what it says?"
Sasuke crossed his arms and said with pride, "It's our clan's sacred artifact, so everything written here should be true. But..."
Naruto cut in. "Huh! Genjutsu? How can a Genjutsu possibly help achieve peace? It's bullshit! Isn't a Genjutsu just a fake illusion techniques?"
Kakashi was slightly surprised by Naruto's insight. He glanced at Sasuke and asked, "What were you about to say?"
Sasuke said, "I... I was also about to say the same thing as Naruto. Genjutsu for true peace doesn't make much sense. Are you sure you didn't read it wrong?"
Kakashi shook his head slightly, and said while changing the topic. "Well, enough talk. Let's search for any other Jutsu scrolls here, if this place has any hiding spots, because I don't feel like there's anything else here."
Sasuke didn't question him further. He and Naruto started looking for any scrolls with Uchiha Clan techniques.
Meanwhile, Kakashi stared back at the stone tablet and muttered, "It also says how to attain the Eternal Mangekyō Sharingan and the Rinnegan, from the point I can decipher it. An Uchiha, a descendant of Indra, ''must combine'' their chakra with that of a Senju, a descendant of Ashura. Ha..."
Kakashi chuckled and thought, 'Madara and Itachi both definitely read this. Madara used this to attain both the Eternal Mangekyō Sharingan and letter Rinnegan as well, while Itachi only desired to give his Mangekyō to Sasuke so he could attain the Eternal Mangekyō Sharingan. Maybe this also highly influenced Itachi's later actions, his desire to end the conflict at any cost.
But poor souls, Black Zetsu has altered a lot of things. The warning of the Infinite Tsukuyomi has been changed to a destiny, cooperation between the Uchiha and Senju Clan isn't written here, and the warning not to pursue the Rinnegan is also gone. Maybe even the Mangekyō Sharingan's unlock process was also written by Black Zetsu. And most importantly, the word ''Genjutsu'' for the Infinite Tsukuyomi is also missing here.'
Kakashi sighed heavily, thinking that Itachi had probably recognized the danger of the Uchiha pursuing power and had sided with the Konoha Council after reading this as well, otherwise considering his real self, annihilation of his own clan was also would be hard decision for him... though it still was the toughest decision of his life.
Kakashi also thought about how both the ''Ghost of the Uchiha'' and the ''God of Genjutsu'' were thoroughly manipulated by this stone tablet. He shrugged these thoughts off, don't want to dwell on them any more and then scanned the main chamber of the Naka Shrine, before shook his head in disappointment.
"I don't think there would be anything worthwhile here, especially not a scroll for Izanagi." muttered Kakashi in low voice.