In an alternate dimension that closely resembled the outside world.
—Chibaku Tensei!
The earthshaking roar subsided. Down in a hollow, the boy clenched his hand.
Crack, crack, crack...
After a scattering of earth and stone fell away, an enormous Heavenly Star hung high above the alternate dimension.
In the distance, the Black Zetsu Formation threw up his arms and cheered. "Brilliant!! Naruto, you've already mastered the power of the Rinnegan!!!"
"Black Uncle~." A radiant smile spread across Naruto's face as he lay back on the ground.
His hair was black with a reddish tinge, and his eyes were two different Rinnegan. His left eye was pale purple with three concentric black rings, while his right had six tomoe set into the same pattern.
The readers had probably already forgotten what had happened to Naruto.
After the Fifth Battle ended, Black Zetsu stole secrets about the future through Kabuto. He then changed his plans, choosing... to train Naruto, Asura's reincarnation, as the new executor of his plan to save his mother.
While Jiraiya and Orochimaru were catching up, he abducted Naruto. Taking inspiration from the White Cursed Seal Orochimaru had bestowed on Sasuke, he used his own ingenuity to develop a black cursed seal suited to Naruto.
During that time, Madara's consciousness within the black cursed seal grew so powerful that it briefly took control.
That gave rise to the being known as "Madara." He attacked the Five Kage Summit, then Kabuto, Itachi, and Nagato, repeatedly breaking through the limits of his power using Naruto's body.
The black cursed seal also rapidly progressed from state one to state three.
Well... while trying to seize the Nine-Tails' chakra, he did suffer a setback thanks to the combined efforts of the Nine-Tails, Minato, and Minato's wife. Thirty percent of the black cursed seal's