Beneath the moon's surface, within the Sealing Space.
Time turned back to before Isshiki escaped the Six Paths Life-and-Death Shogi.
Just outside this seemingly impregnable seal, a peculiar life-form composed entirely of Yin-Yang Release, resembling black asphalt, was so excited he nearly lost his shape.
Trembling, he extended his pitch-black, viscous "hand," shaped like a chicken's claw, and carefully touched the seal's outer wall again.
This time, it was not another futile attempt like the countless others he had made recently. Instead... he passed through!
His body had actually corroded a tiny opening in the invisible barrier that completely isolated Kaguya from the outside world!
Silent ecstasy erupted within Black Zetsu's consciousness.
A thousand years! A full thousand years!
He had lurked, schemed, manipulated, and waited, watching Indra's and Asura's reincarnations repeat their cycles of conflict and cooperation, watching dynasties rise and fall in the Shinobi World as wars raged. Hadn't all his patience and effort been for this very moment?
Ever since he noticed that his touch seemed to cause an extremely faint decline in the seal's "activity," Black Zetsu had begun eroding it with the utmost secrecy and patience.
Using the faint power of Yin-Yang Release within him, inherited from Kaguya, he had seeped into, assimilated, and worn away a weak point in the seal bit by bit, like water wearing through stone.
Finally, today, at this very moment, he had succeeded!
Without the slightest hesitation, Black Zetsu compressed and reshaped his muddy body, struggling to squeeze through that minuscule opening.
Kaguya's immense, oppressive chakra within the seal drew him like a magnet.
"Mother!"
The instant he entered the seal, all Black Zetsu's disguises, restraint, and cunning vanished.
He gave a silent cry brimming with overwhelming emotion, transformed into a streak of black light, and hurled himself recklessly