Disclaimer: I do not own Naruto and only use it for entertainment purposes.
Because he was the closest to his cell Itachi, Kabuto was unconscious after the Tsukiyomi (Underworld Moon) was the one the most affected by Naruto's release of Kyuubi's chakra. The S-class Missing-nin had to use all of his considerable mental strength he developed over the years of being a Genjutsu Master to keep himself from fainting from fright. Being so close to Kyuubi's chakra was a reminder of his childhood, when the Kyuubi attacked Konoha. The traitor Uchiha was old enough to remember the awesome power he felt from the Kyuubi and remembered that even the most hardened shinobi would collapse in just fright alone. As a child he was even more affected and the Kyuubi became one of Itachi's childhood fears, the kind that no matter what a person experiences the fear would remain in the back of one's head just waiting to come out.
It was this fear that drove many of Itachi's actions in his life. As a child growing up in the recovering Konoha from the Kyuubi attack he was constantly reminded of the strength the Yondaime showed in not just facing the Kyuubi but also by defeating the Great Beast. As an Uchiha he was raised never to fear anyone or anything so in his childhood he rationalized if he could become stronger than the Yondaime he would never be afraid of the Kyuubi again, thus being a true Uchiha. So he decided to push himself harder than most ninja three times his age, and his hard work paid off, he became one of the strongest shinobi Konoha ever produced. Even then he found himself lacking when it came to the accomplishments of the Legendary Yellow Flash of Konoha. Itachi could defeat anyone he fought, but the Yondaime defeated entire armies, Itachi could use any jutsu he saw, Yondaime invented jutsus that cause men to quake in fear at their mention, Itachi could fight a Class-B Demon to a stand sill, the Yondaime defeated the strongest of the Great Beasts. No, no matter what Itachi accomplished in his relatively short life he could not stand up to a Legend like the Yondaime.
Then in the accident that killed his best friend, Shisui, Itachi obtained the one thing that may put him on the level of the Yondaime, the Mangekyo Sharingan. This gave him access to extraordinary powers in Genjutsu and Katon (Fire Element) jutsu. The problem was he lacked control. This eventually led Itachi to the reclusive Guree Hanyou (Grey Half Demons). A rare Hanyou tribe that were masters of Genjutsu and Katon jutsus. Itachi was somewhat surprised to learn that they were the ones that taught the first Uchiha after the mutation of the Byakugan that led to the Sharingan. Their price for helping him was to help them slaughter the Uchiha Clan for backing out of their ancient deal. Itachi eventually complied and he became a user of Black Fire, a Youkai power, and a Genjutsu Master without rival. Still even after he destroyed his own Clan Itachi felt he was still too weak, he needed help, in his mind the Yondaime would not. So Itachi left to find a way to become stronger. Thus leading him to Kuromaru and his plan to enslave and use the Great Beasts, the way to prove he was stronger than the Yondaime by being able to defeat and then enslave the Kyuubi.
But at this moment Itachi felt only fear and self-loathing. Fear because he was going to face his childhood nightmare and self-loathing that he was feeling the fear. When the walls, ceiling and ground started to shake and break Itachi did the only thing he could do, grab Kabuto and escape. On the way out after narrowly being impaled by a sharp piece of stone Itachi thought, "I am still not over it, I could barely stand to be so close to it. And it was not even using all of its power."
Not far away Kisame looked over the shredded corpse of three of the Oto-Go (Sound Five). They were not much of challenge for the Kiri (Mist) Missing-nin. Once the Curse Seal's power was taken away they were to tire to put up much of a fight. "Samehada (Sharkskin) was satisfied with their chakra and blood but I'm a bit disappointed, I thought they would have been more fun," Kisame thought as he ran out of the Oto base.
He may have been insane by just about anyone's standards but he was no fool, one did not become a S-class Missing-nin by being one. He knew he was in over his head. The amount of chakra being produced was awe-inspiring, not too mention attention getting. Kisame would not be surprised if every person shinobi or not in one hundred kilometer felt this out burst of power. "I wonder what the Leader is doing?" Kisame thought, "He's probably the only person I know that would probably not be affected by this much power."
Kuromaru, despite what Kisame thought, was in fact affected by the output of charka Naruto was producing. Unlike the others however he was not awed or frightened by the act. He was angry. Not at Itachi but at himself and Orochimaru. Himself for understanding the amount of power the vessel could control and at Orochimaru for forcing the vessel to use so much power. No doubt whatever search teams were looking for him would converge on this location, not too mention the idea of fight the vessel at this level of power in an open battle was not something Kuromaru wanted to do. He was strong yes, the strongest of the Akastuki and he may even be able to fight a vessel of a Great Beast alone, but not for very long and not in a direct confrontation. Even with Kisame and Itachi he calculated he would not win, hold off yes, win no. Simply because there was too much power and an unknown number of shinobi were converging on this location.
Looking down at Orochimaru, Kuromaru frowned behind his cloak. "I could kill you know," Kuromaru said to the half dead Snake Sannin. "But I think it would be better if you were captured, if you survive this at least. You reached too far for your foolish goals. That always was your greatest weakness Orochimaru, you did not know your own limitation and now you will reap those mistakes."
While Orochimaru was half dead he was fully aware. A unique skill Kuromaru developed over the years allowed him to keep his enemies awake, but still helpless, when normally they should have been unconscious from pain or fatigue. He heard every bit of what Kuromaru said and loathed every word of it. Orochimaru had always considered himself superior to all but a few people, and those people Orochimaru thought it was only a matter of time until he was. To hear someone say they were stronger, no matter how the said it, always grated him. Whether it was his late sensei Sarutobi, the Yondaime, Itachi, or Kuromaru, Orochimaru despised being told he was weaker then them and the people saying it. Not that he could do much about it. Orochimaru could not move a single muscle much less speak or attack Kuromaru at the moment.
When Kuromaru turned away from him Orochimaru became absolutely livid. Watching the leader of Akatsuki literally merge with the shadows in the crumbling chamber Orochimaru screamed inside of his own mind, "I WILL SURVIVE THIS. AND I WILL DESTROY YOU ALL!" It was too bad for Orochimaru that a practically large piece of stone collapsed not long after his vow and crushed his stolen body.
Inside his cell Naruto continued to focus his raksha and Kyuubi's chakra into the earth around him. He could feel every seismic vibration be produced that was causing everything in a ten kilometer radius to be destroyed. A part of him, one not dedicated to control, was amazed at the power. Most often even the most power Ninjutsu could at best take out a large building. This was taking out a reinforce military compound and the immediate surrounding area. Simply put Human chakra or raksha alone could not produce this kind of devastation. The only reason Naruto could was because he was not completely Human. He was a Hanyou with access to a Great Beast's chakra, his own chakra and raksha all at once. Still that part of his mind was in the minority, though it would probably grow later, and did not distract Naruto from his goal, escape.
When the first streams of sunlight broke through the collapsing ceiling and Naruto looked up he could now see just how far underground he was. By his estimation he was at least one hundred meters below ground. What was the most impressive sight about what was happening around him was that the seals keeping him from moving were still intact. "Those seals must have used several living sacrifices to hold up with this amount of power," Kyuubi commented. "Looks like a little more power will be needed." With just a trace of more effort Kyuubi sent a burst of his chakra through the seal and into Naruto's body.
On the outside another tail started to emerge from the base of Naruto's spine. It was not a fully formed tail but it certainly caused a significant spike in power. The onrush of the chakra literally shattered the surrounding area blowing the ceiling out like a volcanic eruption.
In the village of Homai Sasuke was shivering in fright as everyone else in the village was in a mad panic to run away. What froze Sasuke in place was that not only could he feel the chakra but be could also see the charka. He could see the pulsing red chakra, and something else he could not identify, coursing through the ground and recognized it immediately. "So this is what Naruto has accomplished in the last three years!" Sasuke thought absently. "I…I have to get out of here! This is too much!" Sasuke finally succumbed to his fear and started to run out of the village like many of the Oto-nins around him.
Along the way he thought he caught a glimpse of a black cloak with read clouds but at the moment he did not think about it. As he was running he saw and felt the spike in power course through the ground. He knew he could not run fast enough and was desperately looking for a way to escape the explosion that was about to happen. In his desperation the Evil Containing Seal keeping the Curse Seal away shattered and the Curse Seal immediately activated going right to Level Two. With his transformation Sasuke took to the sky just as the ground around him blew out from under him. With the incredibly strong updrafts Sasuke soared into the sky and had a bird's eye view of the destruction that was occurring. The entire village of Homai was blowing apart in a huge explosion of force.
Fifteen kilometers away from the epicenter and soon to be large crater Anbu Team 12 and Gai were stuck fighting keep from being overwhelmed by Naruto's attack. Each one was an extraordinary individual in terms of strength but all had to struggle against the onslaught of power. Gai and Lee had unleashed the Third Chakra Gate and were still on their knees and were contemplating opening the fourth. Neji was using a bi-laired Kaiten (Heavenly Spin), formed by chakra and raksha, to keep himself upright. Tenten produced a large custom-made chakra reinforced shield and was hiding behind it kneeling down. And Lea'so had shifted to her Youkai form and was digging her claws into earth to steady herself.
What was strange about this group was they were not feeling the fear that most of the other people were in the area. Maybe it was because they all knew Naruto would not harm them. Or maybe it was because they could sense no malice in the attack, just an extremely high level of power.
"At least we know Naruto-kun's alive!" Lee said straining his voice.
"That's an understatement Lee!" Tenten shouted.
"Brace yourselves!" Neji shouted. "A huge spike is coming!"
The others took head of Neji's warning and intensified their defenses. When the blast reached then they were all knocked off their feet and thrown nearly twenty meters back. It was only because of their extensive training that they were able to stand with only relatively minor injuries. When they stood and surveyed the damage they were stunned, even Lea'so. Fifteen kilometers away there was a massive create at least five kilometers across and the surrounding area nothing but ruble. Even in their immediate area hundreds of trees were toppled over, huge boulders had crumbled to pebbles and all wildlife seemed to have fled the area. Still even with the amount of destruction they were only worried about one thing, or rather one person, their friend and teammate Naruto.
Author's Note: I know this is a bit short aft so long but I feel this is the best place to end this chapter. I thank all my readers for their patience and I hope you enjoyed the update.
Also I have had some comments about the use of Shunhsin (Body Flicker) instead of Hirashin (Flying Thunder God) and I would just like to say that when I started this story the source I used listed the Yondaime's jutsu as Shunshin. I will correct this error in my earlier chapters but it may take a while.