The power of Amaterasu was immense.
The briefest touch from the black flames forced Danzo Shimura to activate Izanagi to escape, a move that completely exposed his forbidden jutsu. The moment Danzo reappeared, a surprised Itachi guessed he must have used the Sharingan's ultimate dōjutsu, Izanagi.
However, he immediately dismissed the idea.
Itachi reasoned that Danzo's Sharingan was hidden in his bandaged right eye. Using Izanagi would have cost him that eye, and if Danzo had a Sharingan, it had to be the precious Kotoamatsukami he had stolen from Shisui. Surely, Danzo wouldn't waste such a powerful eye—one that could bend reality itself—just to cast Izanagi, would he?
Itachi felt he had a decent understanding of Danzo. While the old man was afraid of death, he was also the type to gamble his life for certain advantages. He would be cautious with his life for great matters, but risk it all for small gains.
That was Danzo Shimura.
Using a Wind Style jutsu, Danzo blasted an exit from the Root headquarters, finally escaping the pursuing black flames of Amaterasu. However, Itachi Uchiha and Kisame Hoshigaki were not the least bit slower. They were right behind him, intercepting him on the surface.
The one-eyed old man slowly tore the bandages from his right eye and said coldly, "To enter Konoha and try to assassinate me... you have some nerve, Itachi!"
Danzo had never thought Itachi would dare. According to his understanding, the Uchiha who had been brainwashed by the Will of Fire should value Konoha's interests above all else. How could he assassinate him, the leader of Root? Had he forgotten what Root meant to Konoha?
Facing the Mangekyo Sharingan, Danzo didn't dare to be careless. He instantly uncovered his right eye, revealing the Kotoamatsukami he had taken from Shisui.
"I was just here to gather information," the rogue ninja said, shaking his head. Because Kisame was beside him, Itachi didn't speak a single word of truth. "Since we happened to meet... it wouldn't hurt to see you off on your way, Lord Danzo."
"Itachi Uchiha..." Danzo gripped the ninja sword in his hand, trying to continue his threat. "Do you know what you're doing? You are breaking the agreement we had..."
"The one who broke the agreement was always you, Lord Danzo!" Itachi shouted, interrupting him. A kunai spun nimbly in his hand as he flew toward Danzo.
Kisame Hoshigaki gripped his Samehada greatsword and charged up alongside Itachi. Hearing their exchange, he couldn't help but blink his small eyes curiously. "Mr. Itachi, what kind of agreement did you two have?"
The shark-faced man felt something wasn't right. They were supposed to be gathering intelligence, so why were they trying to assassinate a high-ranking Konoha official? He had been sent by the Akatsuki's secret leader to monitor Itachi, and now it seemed he had stumbled upon some incredible information. If he could uncover Itachi's hidden secrets in this battle, it would be good for the stability of the Akatsuki.
Kisame didn't know that the "agreement" between Itachi and Danzo wasn't much of a secret to the man behind him. The Akatsuki had even held off on attacking Konoha just to recruit Itachi.
Of course, a sadder truth awaited the shark-faced man. Itachi Uchiha had already decided Kisame's fate. In this battle, he planned not only to kill Danzo but also to seize the Kotoamatsukami. The rogue ninja's plan was simple: once he had the eye, he could use it to completely change Kisame's will.
Once the partner assigned to him by the Akatsuki was on his side, things would be much easier for Itachi, whether it was passing information to Naruto or protecting Sasuke. With Kisame controlled by Kotoamatsukami, Itachi would no longer have to worry about pressure from the Akatsuki and could continue to lie low, hiding even deeper and gathering more intelligence.
Naturally, Kisame couldn't imagine his teammate being so shameless. Unaware of the bizarre powers of the Mangekyo Sharingan, he was still naively dragging Samehada along to double-team Danzo with Itachi.
Killing a "Darkness of the Shinobi," is that also a kind of honor? he wondered.
"Tsukuyomi!"
The light in Itachi's Mangekyo Sharingan flashed. Danzo had no time to look away. He was helpless as his consciousness was dragged into the pitch-black, gloomy world of Tsukuyomi.
Itachi was displaying a level of power completely different from the past. He unleashed his Mangekyo dōjutsu without a second thought, no longer worrying about the risk of blindness. This display made Kisame's eyes twitch.
Usually, on missions, Itachi would throw a shuriken, maybe use a Great Fireball Technique, and at most, open his three-tomoe Sharingan for a simple genjutsu. But when sealing the Third Hokage, he had directly summoned Susanoo. Now, to kill Danzo, he opened with another Mangekyo dōjutsu.
One ultimate technique after another... Mr. Itachi was truly a ruthless man.
If Kisame could see what was happening inside Tsukuyomi, he'd realize that "ruthless" was a massive understatement.
A blood-red moon hung in a crimson sky. The world of Tsukuyomi was filled with a deep scarlet light. On the blood-red ground stood a black chair and a desk. Danzo found himself sitting at the desk. He could vaguely make out a hat on it. A blood-stained hat. With his years of coveting the position, Danzo recognized it at a glance: a Konoha Hokage hat.
Even though Danzo didn't know where he was, he understood the ominous atmosphere meant danger.
"You really want to sit in the Hokage's seat, don't you... Lord Danzo."
A pitch-black figure materialized from nothing, appearing beside Danzo, his hands gripping a ninja sword. From the silhouette and the piercing red Sharingan, Danzo immediately recognized Itachi.
"Where is this place...?" Danzo demanded, trying to maintain the dignity of the Root leader. He needed to project confidence. "You want to kill a high-ranking village official inside Konoha? Itachi Uchiha, besides me, no one cares about that agreement. Sarutobi is dead. If I die at your hands, no one in all of Konoha will ever know your identity. Are you sure you want to betray your own village?"
"Still so arrogant..." Itachi looked down coldly at Danzo. "Then I'm truly sorry. Someone has made a new agreement with me. Compared to you, I believe he can protect Sasuke better..."
Clang!
As soon as the words fell, a sharp blade flashed.
In an instant, Itachi's sword sliced through Danzo's neck. But as his head rolled onto the desk, Danzo realized he wasn't dead. His eyes could still see everything happening in the Tsukuyomi space.
He would have rather died.
Because within his line of sight, countless other Danzos, each sitting in a chair, were being beheaded by the Itachis standing behind them. What terrified him was that as his own head fell, a new one began to grow from his neck, only for the Itachi behind him to mercilessly swing his sword again.
In the entire blood-red space, all the Itachis were repeating the same action, their voices echoing the same words: "You're useless now... Lord Danzo."
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Bonus:
Itachi: I must choose the right path for my teammate...
Kisame: Mr. Itachi, you don't have to...
Itachi: I must help him find the meaning of life!
Kisame: Mr. Itachi, you really don't have to...
Itachi: It's a must. We are teammates!
Kisame: That crow on your shoulder... it doesn't have Kotoamatsukami, does it?
Itachi: ...Hmm.