One hundred kilometers south of Konoha, at the Nameless Mountain, Habara temporarily halted the digging project after a month of work and came here… Of course, while he had the chance to come up for a breath of fresh air, the other two unfortunate humans remained in the cold, lonely depths.
Habara wasn't alone. Three other people were present: Shiranui Genma, Namiashi Raido, and Tatami Iwashi. These were the Fourth Hokage's former young subordinates, ninja who, aside from guarding doors, weren't particularly useful.
However, since the Nameless Mountain no longer held anything that needed guarding, their presence here was at Habara's request.
The four were currently squatting in a circle, a large unrolled scroll spread out in the center.
"This is a barrier array designed by Kushina-sama. Once activated, it will isolate this Nameless Mountain from the outside world…" Habara explained, pointing to the incredibly complex formula on the scroll.
To be honest, Habara couldn't fully understand the entire barrier sealing array. Kushina had only taught him how to set it up. As for the underlying principles, given Habara's…intellectual limitations, Kushina hadn't bothered with a detailed explanation.
But Habara trusted Kushina's abilities. No matter what, the barrier sealing array she designed was the best, because no one in the world was more skilled in this area than she was.
"It's clear that activating this kind of seal requires a massive amount of chakra," Shiranui Genma stated the obvious.
"Chakra won't be a problem. We'll have it when the time comes. The issue now is that this barrier isn't complete. If someone with the ability to forcibly enter the barrier in an incorrect way appears, I want to set up an entry point where they breach it. This entry point will directly connect to an 'exit' located elsewhere, regardless of direction, thus making this Nameless Mountain a place that can never be reached…
To achieve this, we'll need a corresponding space-time ability. I believe you can guess why I've asked you all here."
The three exchanged glances, and then Shiranui Genma said, "The Flying Thunder Formation Technique."
The Fourth Hokage had once taught these three the Flying Thunder God Technique. However, they had learned the Flying Thunder Formation Technique, which required all three of them working together to activate… Despite only a single character difference, these were clearly two different things.
The Flying Thunder God Technique allowed the Fourth Hokage to become the fastest ninja in the shinobi world, earning him the name "Yellow Flash." But the Flying Thunder Formation Technique… well, it was a technique that was hard to describe in a few words.
In short, Flying Thunder God was an instant teleportation technique, while Flying Thunder Formation was a teleportation technique with a casting time.
As long as the Flying Thunder Formation formula was inscribed beneath the Nameless Mountain and kept in a ready-to-activate state, then no one would ever be able to intrude here again… because anyone who tried would be immediately thrown out.
"Can you do it?" Habara asked, seeing that the three fully understood his intentions.
The three discussed it briefly before giving their answer, "We can give it a try."
It wasn't a particularly difficult task, especially compared to using the Flying Thunder God Technique in combat.
"Excellent." Habara smiled. If these three couldn't handle this job, their futures really would be limited to guarding doors.
Leaving the three to begin resetting the formulas here, Habara returned to Konoha.
Meanwhile, with the digging duo.
"At this rate, it'll take two months to dig through this tunnel. This mission is truly agonizing," Kakashi couldn't help but complain.
It was understandable that he was a little frustrated. The work itself wasn't difficult, only digging one or two kilometers a day, which wasn't unbearable for a ninja. However, because he was constantly underground, Kakashi felt like he'd been sold into slavery at a black coal mine.
"Really? Compared to other things, I find this to be a very simple mission." In contrast, Tenzo found the current mission incredibly easy. He even found a sense of joy in this repetitive work… He didn't have to worry about encountering enemies or being locked up on an experiment table to be studied. Just digging tunnels, what wasn't there to like?
"Cherish it while it lasts. Simple, long-term missions like this are rare," Tenzo even turned to advise Kakashi.
Before he could finish speaking, a rumbling sound from ahead made them stop talking. Clearly, something was rapidly approaching them.
Kakashi and Tenzo instinctively felt a threat. In the blink of an eye, they were on high alert, ready to meet the incoming challenge.
Tenzo looked around and couldn't help but frown. This overly narrow environment was clearly unsuitable for a ninja battle.
"It's coming!" Kakashi warned.
Suddenly, directly in front of the tunnel they had dug, dirt and rocks came crashing down. As the bottom layer was breached, a giant, triangular, cyan snakehead appeared before Kakashi and Tenzo.
Tenzo instinctively began forming hand seals, but Kakashi noticed the snake's eyes… That's right, this snake had eyes.
It looked at the two humans with a gaze full of curiosity mixed with sympathy. Then, after flicking its tongue, it turned around and retreated the way it came… Another "slave" caught by that person, what was there to fight about? A meeting like this was fate.
The snake was surprisingly philosophical.
"That should be… the summoning animal Habara captured earlier, right?" Seeing the snake leave directly, Tenzo remembered Habara mentioning something about "Gamabunta's relative." "Habara captured three summoning animals and let them roam free around the Nameless Mountain… See, I told you this mission was worth cherishing. The other half was clearly snatched up."
...
Just after Habara returned to Konoha, before he could re-enter the sunless underground, a ninja suddenly approached him.
Judging by the attire, it seemed to be a Root ninja.
"Upper Jounin Habara, Danzo-sama requests your presence."
Sure enough, the ninja's opening words confirmed his identity.
"Danzo? Danzo-sama?"
Habara thought for a moment and decided that a formal meeting with Danzo wouldn't be a problem. After all, the man had invited him several times before. He just didn't know what Danzo wanted this time.
But it probably wouldn't be anything good.
"Lead the way."
It didn't matter, though. Habara no longer had any reason to fear Danzo. He represented Konoha's new changes, while Shimura Danzo represented its continuous decay. So, what was there to fear… Okay, the main reason was that after obtaining the Dragon Vein, and comparing his current strength to Danzo's, Habara wasn't afraid of Danzo ambushing him with five hundred swordsmen when he went to meet him.
In any case, following this Root ninja, Habara didn't enter a sunless underground space, but instead arrived at Konoha's truly sunless underworld.