Rinne-Sharingan

Red chakra entered Kuro's body through his hand and coursed through his body in an instant before heading and accumulating on his forehead.

[Unknown energy detected in the host's body!]

[Analyzing...]

[Unknown Energy has been detected attempting to corrupt the Host's mind!]

Kuro felt a momentary discomfort in his head before everything calmed down.

[The Host's mind has resisted the corruption attempt!]

[The Unknown Energy is slowly merging with the Host!]

Kuro felt a tingle on his forehead at the same time as a vertical line appeared on it.

As that happened, the two small black spheres on his back grew a little and two other spheres appeared.

The line on his forehead suddenly opened and a red Rinne-Sharingan appeared. However, he only had four tomoes and not nine as it would normally be.

Kuro's perspective changed and the level of clarity with which he saw things increased significantly.

He inhaled and after exhaling he concentrated on the Sakon and Ukon's Kekkei Genkai 

Suddenly, the third eye sank and his forehead returned to how it was before and at the same time, the Rinne-Sharingan appeared in his Left eye, but disappeared again and appeared in his palm.

Seeing that it worked, Kuro moved it back to the left eye before looking around.

Zetsu was half sunk into the ground some distance away watching Kaguya warily.

Kaguya stood at the edge of the mountain looking at the scenery, sometimes in confusion and sometimes calmly.

Zetsu approached Kuro and whispered. "Kuro-sama, what happened to her?"

"Long story short, she lost all her memories." He looked at Zetsu, who was surprised after seeing his left eye.

"That's the Rinne-Sharingan...!?" Kuro nodded.

"But it's pretty weak, I guess from not having consumed the fruit directly. But I had already thought of a solution, how did it go with what I told you to do a while ago?" Kuro said and Zetsu became serious.

"It went pretty well. With the Sharingan you gave me, I used the Kotoamatsukami on all the Jinchuriki except for Naruto Uzumaki. But it was possible to resurrect Minato Namikaze with the method you gave, and we used Genjutsu on him. The Yin Part of the Kyuubi was sealed inside the Amber Purification Jar after it was extracted." Kuro nodded and thought for a moment before speaking.

"You only used it on the Jinchuriki?" Zetsu slowly shook his head.

"All the Bijuu within them were also influenced. In Akatsuki I only used it on Konan. I'm sure it will be useful, she's who is closest to Nagato and I had to wait a long time for a chance and avoid being discovered. The Kotoamatsukami's reuse time hasn't reset, so I haven't been able to use it on anyone else." Kuro nodded without feeling disappointed.

"Did you bring the eye?" Kuro asked and Zetsu nodded before pulling out the small vial from inside his cloak.

Kuro grabbed it and opened it before breaking the eye down to the molecular level and letting it enter through the pores of his hand.

The System did not take long to detect it and after Kuro's approval, the assimilation began, which was instantaneous.

Kuro concentrated and the Sharingan appeared in his right eye before he moved it to his left. The Rinne-Sharingan spun for a moment and a new tomoe appeared as it stopped.

"Excuse me, could you tell me who you are? And who am I?" Kaguya spoke politely as she approached.

Kuro noticed that her appearance had changed. She no longer had the third eye on her forehead and the horns on her head were also gone. Her hair and nails were also not as long as before.

"Your name is Kaguya, and mine is Kuro. I'll let a clone explain a bit more, since I'm busy." Kuro replied before creating a clone of Wood and sending him off to find Karin and Shiori.

Kaguya was surprised after seeing the demonstration and nodded. "Before I go, is it possible for you to give me some of your blood?" Kuro asked and Kaguya tilted her head in confusion.

However, after a moment she nodded and stretched out her arm. Kuro made a small cut on her wrist and made some blood float from the wound before it healed.

As Kaguya looked at her wrist in surprise, Kuro broke down the blood and repeated the same process as Shisui's Sharingan.

Once the assimilation was finished, her skin became a bit whiter and her hair grew a bit and was slowly turning silver.

Some notifications of new abilities popped up and Kuro checked them quickly before looking at Zetsu. "Take the clones to the Jinchuriki's location." Nine clones appeared after he finished speaking and Zetsu quickly sank to the ground as the clones followed him.

Since it would be a shame to kill someone who was being controlled, the clones will leave enough chakra in the Jinchuriki to prevent them from dying.

Sensing that the clone was already returning with Shiori and Karin, Kuro looked at Kaguya. "The clone will explain everything." He disappeared right after.

.

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In a mountainous region located between Takigakure and Otogakure, dense forests and bones of giant beasts could be found sticking out. This place is called Mountains' Graveyard.

A figure with four black spheres could be seen floating high in the sky of that mountainous region.

Kuro examined the place and when he found what he was looking for he activated invisibility before teleporting back directly behind Obito Uchiha using the mark Minato had left him.

The fake Madara was in a laboratory reading something. Kuro noticed that the wall was filled with square vials and inside them floated Sharingan eyes.

He ignored it and waved his hand at blinding speed before plucking out Obito's right eye.

"Argh!!!" He jumped back with a cry of pain and opened his left eye wide. However, before he could do or say anything, Kuro pierced his eye with a gray-colored bone.

Obito's body began to turn gray and a moment later, he disintegrated into a pile of ashes.

Kuro looked at the Sharingan in his hand and did the same as with Shisui's eye and the Rinne-Sharingan spun again.