"No matter what happens next, we can't let a mass murderer like Disonasu walk away freely," Minato said as they ran through the pipeline; after several attempts, Sakura had finally managed to cut a hole large enough for them to squeeze themselves into the black tube. "If he's truly turned over a new leaf, then he'll have no reason not to come quietly."
"I agree, but that'll have to wait until later," Sakura said, holding an arm over her bulbous chest to keep it from smacking her in the chin as she ran. "Saving the Tonika and Hachō villagers comes first."
Though darker than the deepest night, the walls of the pipeline pulsed faintly with jagged, angular lines of crimson light. There was no longer any doubt in Sakura's mind that they had stumbled upon some ancient, abandoned Ōtsutsuki relic, for who but the Ōtsutsuki could have installed such a vast and futuristic network of pipes beneath the earth?
What's more, the concentration of nature energy inside was many times higher than outside, comparable to that of the unexplored sage regions. Given that the surrounding area was a lifeless wasteland, Sakura was certain these pipelines were draining nature energy from the region and accumulating it in the Hole... but to what end? That, she could not say, though she had a sneaking suspicion that Disonasu might know the answer.
"There's someone ahead," Minato said abruptly.
They soon emerged into a perfectly circular chamber. The floor beneath their feet glowed with the same crimson lines as the walls of the pipeline, spiralling in regular geometric patterns towards the centre of the room, where an old, grey-bearded man clad in brown robes awaited them.
"Oh, great heroes of the Leaf, you've finally come!" he said in relief, his gaze falling upon the emblems engraved into their forehead protectors. "I was beginning to think we'd been abandoned to our fates…"
"Disonasu, you're a wanted man in all five of the great countries," Sakura said coldly. "Care to explain what you're doing here, instead of in the village you're supposed to be leading?"
Hachō Village was a settlement a few kilometres from Tonika Village that barely subsisted on the water it pumped out of the Hole through a pipeline; the ordinary kind made of metal, not the strange black conduits Sakura and company had used to sneak right under Tonika Village.
"I barely made it out of Hachō Village myself…" Disonasu said weakly. "I'm just an old, crippled man, looking to live out the rest of my days in peace…"
"Cut the act, murderer," Raidō spat. "If you wanted to play innocent, then why did you tell us your true identity?"
Disonasu's eyes narrowed dangerously.
"I apologise, I was under the impression that the Hidden Leaf was in such dire straits it would even resort to welcoming its worst criminal back into the fold," he said coldly, referring to Orochimaru. "Revealing my identity was meant to earn your trust and demonstrate my worth, Hokage... but it seems I no longer need to keep up the pretence and spare you the embarrassment of being seen negotiating with a common murderer by your subordinates..."
Sakura shrugged.
"Orochimaru's a special case," she said, planting her hands on her hips. "Now, what is it exactly you're hoping to get out of this? We've got Iwa-nin to rout and villagers to rescue."
Disonasu licked his lips.
"I want—"
His voice trailed off as he accidentally met Sakura's scarlet eyes, the three tomoe orbiting hypnotically around her pupils.
"The Saezuri controls the Ama no Hoko. Seven colour-coded rods must be installed in the device in a specific sequence to either activate it, release its power, or deactivate it," he said, his eyes glazing over. "I have recorded the sequences in a book I keep on my person, next to the scroll that contains the Saezuri, but I do not hold the rods— they have been seized by the invaders. I intended to get you to fetch them on my behalf, then double-cross you and take the Ama no Hoko's power for myself."
Somehow, Iwagakure had learned of Tonika Village's secret, it seemed… or perhaps not.
"And the villagers?" Sakura asked.
"They are irrelevant," Disonasu said dully. "Hachō Village's militia was completely exterminated. I do not know what happened to the rest."
Too busy running away to the catacombs to see what had happened to them, no doubt.
Now that she knew Disonasu was an irredeemable monster who intended to betray them, Sakura nodded to Minato and drew her thumb across her throat, and without much more ceremony, he slit the old man's neck with a Flying Thunder God kunai.
"Once we get aboveground, I can look for survivors," Minato said. "As long as they're touching my Nine-Tails' chakra cloak, I can teleport them all at once."
"What about this Ama no Hoko thing?" Iwashi said. "What should we do about it?"
"Apparently, it's useless without this Saezuri controller thingamajig, so the enemy can't make use of its power until they get their hands on that gizmo," Sakura said as she patted down Disonasu's lifeless body. "We can decide what to do with it later... but just in case, if you see those coloured rods, you can grab them if you want."
Sakura pocketed Disonasu's lorebook and the scroll containing the Saezuri. From the old man's explanation, it seemed this entire array was some kind of pseudo–God Tree, designed to steal the planet's nature energy and condense it into a chakra fruit, or infuse it into something else entirely like a charging port. The only reason the Hole existed as an oasis was likely because the energy was leaking somewhere, returning a fraction of the planet's lifeforce and concentrating it into this small area.
"Hang on, how are we supposed to get out of here?" said Genma, scratching his head. "I don't see any exits."
"Ahaha…" Minato laughed sheepishly. "Maybe killing that guy was a little premature…"
"Stand back," Sakura sighed. "I'll open another hole…"