Inside the Tsukuyomi space.
When Itachi Uchiha raised his ninja sword to look at Naruto Uzumaki, a look of horror flashed across his face. In his vision, Naruto's body was gradually becoming enormous. The boy's spiritual energy was too vast, so powerful that it was beginning to overwhelm the genjutsu itself.
Because Naruto was no longer restricted by his physical body within the Tsukuyomi, the memories that had been sealed by the time-travel jutsu began to unseal, floating to the surface of his mind.
Faces from a long life flashed through his brain: Kakashi, Sasuke, Sakura, Jiraiya, Obito Uchiha, Madara Uchiha, Kaguya Otsutsuki… Among them was the very same Itachi Uchiha standing before him now.
"So that's how it was..."
Tears dripped from the corners of Naruto's eyes. A single tear was larger than Itachi's entire body, startling the Uchiha and making him take an involuntary step back.
Naruto closed his eyes, letting the tears stream down his cheeks as he recalled the scenes from his memory, one by one. He sighed in a low voice, "What a long dream..."
Itachi looked up at the massive form of Naruto in astonishment. "How can your spiritual energy be so powerful..." he said in a deep voice.
"Because I've lived for too long."
Naruto's tears fell continuously. He spoke slowly, like a dying old man. "Back then... it must have been a hundred years from now. To extend my lifespan, Kurama—whose chakra was the closest to the Ten-Tails—found a way to give all of its chakra to me..."
That proudest of all the Tailed Beasts… when its jinchuriki was on the verge of death, it could have broken its shackles to gain freedom. Instead, it chose to merge its chakra with Naruto Uzumaki to extend his life.
In doing so, the fox forever lost its power. Its size was reduced to that of Pakkun, unable to even contend with some common ninja beasts. Kurama hadn't even stopped to think about how, after Naruto's death, it would survive in the ninja world once the Tailed Beast revival mechanism brought it back.
After Naruto was first reanimated by Orochimaru in that future, he had asked the Sannin to track down the Nine-Tails, but there was no result. Perhaps its power was too weak for it to survive in the harsh ninja world.
"Itachi Uchiha..."
Naruto looked down at the small black figure on the ground and said softly, "Because you are Sasuke's older brother, we met a few times."
"Oh... when you were a child?" Itachi thought back to the time before the Uchiha massacre. "I remember you. Because you were the village's demon fox, many people were unwilling to get close to you..."
Others were unwilling or afraid. Only their Uchiha clan was not allowed to.
"No need to talk about that. While I have this chance, I want to have a chat with the Nine-Tails." Naruto looked at Itachi and said, word for word, "You want Sasuke to kill you, to complete his revenge. You plan to transplant your Mangekyo Sharingan to him so that he can awaken the Eternal Mangekyo Sharingan..."
Clang!
Itachi's body floated up into the air. He looked directly into Naruto's eyes and gripped his ninja sword tightly. "Who... are you!"
This was the biggest secret in his heart. Not even Hiruzen Sarutobi knew of his true intentions. Naruto couldn't possibly have this information. If Itachi remembered correctly, aside from buying paint to splash on the Hokage Rock, Naruto barely even attended class.
"The future Seventh Hokage of Konoha, Naruto Uzumaki."
Naruto looked directly at Itachi's Sharingan and said softly, "Itachi, I know things about your past. I know you were a spy sent by the Third Hokage into the Akatsuki. I know that Danzo Shimura manipulated you into slaughtering the Uchiha clan. I know your purpose."
"..."
The ninja sword in Itachi's hand fell to the ground. He lowered his head. "Then... why are you here?"
"To unify the ninja world, so that there will be no more war."
Naruto sighed softly and began to explain. "After Sasuke and I reached the end of our lives, the ninja world faced an invasion from outsiders and a long period of internal war. The entire world was left desolate. To restore vitality to the world, end the fighting, and change the system of the five great nations, Orochimaru invented a time ninjutsu. He sent me to this era to reverse the future."
"Because my memories and spiritual energy are too vast, they would gradually destroy my body. So, those memories were sealed by the jutsu, leaving only a ninjutsu to give me power and the will to unify the ninja world."
Itachi was a trustworthy person. And once Naruto left the Tsukuyomi space, his memories would be sealed again. Someone had to know the truth to guide him and help him complete his mission. Besides Itachi, the Nine-Tails inside his body also had to know about that hundred-year history. He and the fox were inseparable, and Kurama could help him avoid making critical mistakes.
The look of horror on Itachi's face slowly faded. He asked his first question, "You and Sasuke both reached the limit of your lifespans... why did Orochimaru survive?"
"Because in the future, he can clone himself and use the Living Corpse Reincarnation to change bodies. In a sense, he has already obtained immortality." Naruto didn't hide anything. Although the jutsu granted immortality, Orochimaru's power grew weaker with each transfer.
Itachi thought for a moment and asked another question he cared about in a low voice, "Sasuke... did he have a good life in the future?"
"The first half of his life was spent wandering, trying to kill you. After he learned the truth of the Uchiha massacre, he was lost for a long time. During that period, he was a cold and ruthless person, focused only on avenging you. He didn't care about anyone's life or death...
"It was only after the Fourth Great Ninja War ended that Sasuke returned to Konoha. After that, to protect the village, he abandoned Sakura and his daughter to search for any news of the outsiders... Later, he saw the state of the ninja world and proposed that I unify it. I didn't listen to him. It turned out Sasuke was right."
"Sorry. I failed you. I didn't take good care of him."
Naruto lowered his head in shame. He remembered that when Sasuke was on his deathbed, he didn't blame him. Instead, he said he was atoning for the sins of his early life. Naruto understood what Sasuke meant. He had only spent four years chasing Sasuke to bring him back to Konoha, but that guy had spent his whole life protecting what they had built.
"I see..." Itachi took a deep breath and looked up at the blood-red moon in the sky. "Perhaps that's what he wanted," he said softly. "Perhaps we were all wrong..."
Naruto made a firm promise. "Although we were all wrong in the past, I've returned. This time, I will protect him!"
"What do you need me to do...?"
"The same thing as the Akatsuki," Naruto stated his purpose, watching as the expression on Itachi's face slowly grew complicated. "Collect the Tailed Beasts!"