The cave was the same cave. Madara's grave was somewhere in the dark outside, and the interior still held the particular cold and damp of a place that hadn't seen sunlight in a long time. Obito had been living in it long enough that he had stopped noticing.
He sat cross-legged with a scroll open across his knees, reading. There were more scrolls stacked beside him — the accumulated knowledge that Madara had compressed into his mind through forced genjutsu, now spreading back out into its actual volume as Obito worked through it. Understanding lagged significantly behind possession. He had the techniques the way someone has a library they've never read. The work of actually reading it was ongoing.
"Black Zetsu," he said, without looking up. "When's the right time to approach the Yorozuya? You mentioned them before."
Black Zetsu's expression shifted slightly. On a normal face, this would have been readable. On a face that was half the color of dried ink, it was invisible.
"After Nagato," Black Zetsu said. "That's still the more pressing matter."
"We need our own people," Obito said. "Nagato's one piece. I'm one piece. Having a capable organization behind us makes the whole thing more coherent."
He had been thinking about the Yorozuya since Black Zetsu first mentioned them. S-rank designation from every major village simultaneously. An organization built around someone who, by Black Zetsu's account, operated outside every convention the ninja world had ever established. That description fit Obito's idea of a useful ally considerably better than it fit his idea of an obstacle.
The plan needed people willing to work outside the rules. The Yorozuya were, by definition, exactly that.
Find him. Convince him. Make him useful.
It was a straightforward ambition. He was aware it probably looked more straightforward from where he was sitting than it would in practice.
"I'll watch for opportunities," Black Zetsu said, which was not a yes or a no, and landed somewhere that Obito filed away without examining too closely.
Black Zetsu's position, held internally, was considerably more complicated than what it expressed aloud.
The problem was Rin.
According to every piece of intelligence Black Zetsu had been able to gather through White Zetsu's networks, Nohara Rin was alive. She was inside the Yorozuya's base in the Land of Birds. She was carrying garbage bags and making tea and apparently asking Orochimaru questions about medical jutsu scrolls.
This was not supposed to be possible.
Kakashi had pierced her heart directly. Black Zetsu had watched the incident from a concealed position, had confirmed the wound, had begun processing the downstream effects of her death on Obito's psychology before Obito had even fully registered what he was seeing. The chain of events had been designed carefully: Rin dies by Kakashi's hand, Obito breaks, Obito becomes what the plan requires, Obito carries the Moon Eye Project forward. That sequence had executed precisely as intended.
And then Orochimaru, who had been at the scene for reasons of his own, had apparently done something that shouldn't have been possible, and now Rin was alive and in a criminal organization, and Obito did not know.
Black Zetsu had been working through the implications since learning this and had not arrived anywhere comfortable.
The simplest solution was to have Rin killed. That was the obvious answer. A dead Rin was a Rin who couldn't undo Obito's transformation at a critical moment, couldn't reintroduce warmth and light and all the things that had defined him before Kannabi Bridge into an equation that needed them absent.
The complications were numerous. Black Zetsu's combat capability was limited. White Zetsu was worse. The Yorozuya's base had defensive sealing layers that Sasori had originally constructed and Orochimaru had since reinforced, and attempting to penetrate them without detection was a project that could fail in ways that ended with Black Zetsu being discovered by Finn. Finn, who could perceive things that should not be perceivable. Finn, who was — Black Zetsu admitted this only internally and only because accuracy required it — an unknown quantity of the most dangerous variety.
White Zetsu could probably infiltrate the base. The detection risk was real but manageable.
The risk of Finn noticing was not manageable, not in an environment where Finn was operating on familiar ground.
So Black Zetsu was delaying. Watching. Looking for a window where Rin was outside the base and far enough from the organization's major forces that an intervention was survivable.
The window had not appeared.
For now: keep Obito away from the Yorozuya. Under no circumstances allow Obito to learn that Rin was alive. Under no circumstances allow the two of them to be in the same location.
"New information," said a White Zetsu, surfacing from the ground near the cave wall with the liquid ease that White Zetsu managed and everyone else found unsettling. "From the Rain Country."
Obito closed the scroll. "What?"
"Hanzo of the Salamander. He's moving against Akatsuki. He wants Yahiko, Nagato, and Konan dead, and he wants to absorb whatever's left afterward."
Black Zetsu spoke before Obito could formulate a response. "You should go help."
"Help which side?" Obito asked.
A pause. "Akatsuki's side. Nagato's side. Do them a favor."
Obito thought about this for a moment, looking at the space where he'd stacked Madara's scrolls. "Can Hanzo of the Salamander beat the Rinnegan?"
"No," Black Zetsu said. The word came out flat and certain. Black Zetsu was old enough to have a very clear picture of what "demigod" actually meant in practice when applied to Hanzo. Hashirama Senju had been a ninja god in the only sense that mattered: the sense where the word was not a metaphor. Madara in his prime had been comparable. What Hanzo of the Salamander represented, by contrast, was a shinobi of genuine and formidable ability who had lived in an era where there was no one left to show him his actual ceiling. "Calling him a demigod is a courtesy that has lasted longer than it should have. Nagato carries power that Hanzo has no framework to understand."
Obito sat with this for a moment.
"Then I won't interfere," he said. "Nagato will come through it. But someone with his power, who still thinks of himself as one of the weak..." He trailed off, and something moved through his expression that was almost compassionate. Almost. "People like that don't recognize what they have until the moment they have no choice but to use it. And by the time that moment arrives, everything that led up to it has already done its damage."
He knew this from personal experience. He had been someone like Nagato once.
Black Zetsu processed this and found it tactically sound. If Hanzo's operation against Akatsuki went forward and Nagato was forced into a corner — genuinely cornered, genuinely desperate — the person who emerged from that would be different from the person who went in. Easier to approach. Easier to direct. Less attached to the idealism that currently made him resistant.
"Agreed," Black Zetsu said. "We watch. We don't touch it."
Obito nodded. The cave was quiet again.
Some time passed. The sound of occasional dripping water from the cave's upper reaches. The soft movement of scrolls being turned.
Obito asked: "Can an Uchiha awaken the Rinnegan?"
Black Zetsu considered the answer. The honest version was complicated. The Uchiha bloodline carried the lineage of the Sage's elder son. In theory — with the right chakra, the right eyes, the right external input — yes. In practice, the only path that had ever worked was Madara's, and Madara had needed the Sage's direct intervention even after achieving everything else. Sasuke Uchiha would eventually find another route, but that was years away and required the Sage of Six Paths appearing posthumously to hand him something. Without those extraordinary circumstances, natural Rinnegan awakening in an Uchiha was effectively impossible.
"There is a theoretical path," Black Zetsu said. "Difficult. Requires conditions that almost never align."
Obito went still with the focus of someone turning a question over from multiple angles.
"If I had the Rinnegan," he said, "could I use it to complete Infinite Tsukuyomi?"
"The technical capability would be there," Black Zetsu said. "The execution is a separate question."
"What about the Uchiha clan," Obito said. "If other Uchiha developed the Mangekyō — if a significant number of them did — they could use Susanoo. Susanoo resists Infinite Tsukuyomi."
"Correct," Black Zetsu said, and kept its tone even.
Obito frowned at the ground. The calculation was visible on his face as he worked through it.
The Moon Eye Project was the plan Madara had left him. At its completion, every living person would be caught inside the Infinite Tsukuyomi — drawn into an eternal dream. But Susanoo, deployed by someone who had mastered the Mangekyō Sharingan, could resist the technique's effect. Which meant any Uchiha who achieved that level could remain outside the dream, free to interfere, free to resist, free to be exactly the kind of last-minute reversal that toppled plans that had been decades in the making.
The Uchiha were a clan of extraordinary talent. Given time — given stability, given peace, given the next generation growing up without warfare thinning them — the probability of multiple Mangekyō users emerging was not negligible. It was, in fact, the kind of probability that a careful person doing the math on a centuries-long plan would take seriously.
"Then the Uchiha clan," Obito said, "cannot be allowed to exist when the plan reaches completion."
He said it with the same flat certainty that people use when they have followed a logical chain all the way to its end and don't like where it goes but can't find a flaw in the argument.
Black Zetsu said nothing, and kept the satisfaction it felt at this conclusion somewhere that didn't show on a face that was already impossible to read.
Finn had wondered about this, in the part of his mind that catalogued things he didn't fully understand about the world he'd arrived in. Obito had no personal grievance with the Uchiha clan. He was Uchiha. His motive for helping Itachi destroy them had never been cleanly explained by anything as simple as revenge or resentment. And "wanting the Sharingan eyes" was too thin an answer for an action of that scale.
But the answer was here: the Uchiha clan was a structural threat to the Moon Eye Project, and Obito had now identified it as such. Not from hatred. From math.
The clan that had produced him — that had named him, enrolled him in the Academy, carved space for him in its history even when he was its least-gifted student — would be designated as a problem to be solved before the plan reached its final phase. Because they could resist. Because they had the bloodline to do it.
The cursed clan, as the narrator of this era had it, seemed to attract catastrophe from every direction simultaneously. Danzo resented them. The Hokage lineage suspected them. Orochimaru had already taken their eyes. And now the man claiming Uchiha Madara's name had quietly decided to add them to a list.
They would not know why. They never would.
In the cave, Obito picked up the next scroll and went back to reading.