Obito knew: if he set foot deep within Konoha, he wouldn't be able to escape without Kamui.
A sharp pain pierced his right eye. He instinctively clutched his face—Kamui was weakening. An unknown force was draining his dōjutsu like water from parched earth.
"This thing... it's devouring my power," he croaked.
"OBITO!" The Black Zetsu's voice, usually ingratiating and hissing, turned into the screeching of metal. "Look what you've done!"
The fear in his eyes gave way to a seething, primal rage, the likes of which he hadn't experienced in his entire thousand-year life. This insignificant Uchiha hadn't simply failed the mission—he had created a monster. A threat from which there was no escape. If he found himself within its reach, he, the will of the great Kaguya, would simply fade away. Melt away. Disappear.
A monster. An absolute monster.
— ...
Obito fell silent for a moment under that withering gaze. He himself felt that chilling horror—the feeling of having life forcibly sucked out of you, powerless to stop it.
"I couldn't do anything!" Obito snapped, his hate-filled gaze never leaving Yue's hovering figure. "Who knew that a clan on the brink of destruction would give birth to... this? It's Itachi's fault! He didn't finish him off back then; he gave him the chance to awaken the Mangekyo!
Yes, it's all because of Itachi. If that damned genius hadn't dragged him into the clan's massacre, none of this would have happened.
"Uchiha Itachi!" Black Zetsu hissed hatefully. Because of this dead man and this idiot, Obito had encountered something that could disrupt his millennia-long plan. He wished he could turn back time and stop them both... but alas.
"Don't worry, Zetsu," Obito tried to reassure him, reaching out to the edge of the anomalous zone. "He won't last long. This is just the Mangekyo. Without a transplant, he'll go blind. When his eye power runs out, this field will disappear."
Obito's hand touched the invisible barrier. Power immediately surged from his body. He struggled to contain his chakra, only slowing the leak, not stopping it.
They retreated hastily.
Black Zetsu looked at Obito as if he were not just an idiot, but the epitome of universal stupidity.
"Have you forgotten yourself, Obito? Do you think the Eternal Mangekyo is the only way to preserve your sight?" "Now look at him. This monster drinks reality itself: chakra, light, life. And dōjutsu is just a special form of energy. Do you really believe that by absorbing everything around him, he doesn't also replenish the power of his eyes?" Zetsu's voice trembled with barely suppressed horror.
"No... impossible..." Obito recoiled. "If his power is replenishing, and his sphere of influence is constantly expanding... then the entire shinobi world... No! Absolutely impossible! There must be a limit to everything!"
He shook his head furiously, refusing to accept this monstrous notion. If the entire world were enveloped in this field, then everything he had lived for, his "Eye of the Moon" plan, would be destroyed. The tailed beasts would turn into dry mummies. He refused to accept such a future.
"Who knows..." Black Zetsu whispered, his face contorted. He was trembling. If Obito is only half right, death will come for him even in the depths of the earth. His own death is nothing. But if he disappears... who will bring Mother back? The thousand-year plan, his entire life—all will turn to dust because of this degenerate.
No. NO!
"It doesn't matter if he has a limit," Zetsu's voice became icy and hard as steel. "He must be destroyed. Wiped from the face of the earth. Tear out those damned eyes. At any cost. Even if our plan has to be postponed, we must eradicate this threat."
They vanished in a swirl of Kamui. An ancient will and a broken idealist flew to tell Nagato that the world was in danger. That the time had come to save it. How ironic.
And high in the sky, in the center of a blinding halo, Uchiha Yue soared. He absorbed the power of the world, basking in the sensation of boundless might. The turmoil below him didn't bother him. The fate of this world has already been decided. It will become food for his eyes.
And no one will escape this feast.