Naruto uses the Kyuubi's chakra and sage mode to force his body to adapt to a hazardous environment
"Father! Father look! It’s so pretty!”"
"Oi, Komei-kun! I dare you to hop the fence! Just stick your face in there--Ow! Mom!" "Absolutely not! Do you want to kill him?”"
"Let's take a picture over here, you can see some of the mountain tops!"
Spurts and gaggles of tourists crowded the fence line that separated two worlds. On the other side of the fence--and such a fence stretched out from east to west as far as the eye could see--was a sheer drop. While not terribly high to begin with, the horizontal distance between the crowds and the mists made up nearly two miles.
Distance could not spoil the allure. The thick, rolling fortification of blue-white fog looked elephantine and imposing, even from miles away. Knowing that on the other side lay assured death only augmented its majesty--an eerie, sui gesneris beauty worth traveling to the ends of the Earth just to see once.
The mists reached towards the sky, mingling with the low hanging clouds, so it was impossible to tell where they ended. Peaking out from the thinnest parts of the mist and sometimes visible with the right wind current, were the jagged shadows of mountain ridges. It was often speculated that mountains dotted along the end of the world, contributing to the barrier, else the mists would spill over into their land.
Of course, this was only one theory among many more. No one knew the real reason for the Mists or what held them in place. It was an accepted mystery of life.
Naruto stood amidst the crowd, awed as any other sightseer. No doubt lay in his mind that these were the mists from his dreams. For the first time in days he felt excitement; that trill of happiness fostered from completing one step towards a goal. A goal he did not understand yet.
His head moved from side to side as one would in trying to take in the entire scope of the Mists, while his eyes looked for persons who could obstruct his journey.
He spotted guards--civilian, minimal chakra fluxes--no doubt ninja dropouts from one of the northern, lesser villages. Nothing he couldn’t handle.
There were no settlements directly nearby; the closest village was some miles away, which mean the area would clear out come nightfall. While the panorama would have been worth a shot at tourist profit, the long--time concerns that being exposed to such an environment could cause mutations, sicknesses, or even death kept anyone from inhabiting the region. The mists were vapors, and though the viewpoint was well over a mile away, wind and nature could always find a way to contaminate the good air. Permanent residence was considered a death wish.
Naruto intended to be the exception to that conclusion. He had to try at any rate...continuing as he had been--dulled, confused, plagued by nightmares--would drive him to the brink of insanity.
Naruto moved at the end of twilight, when the human eye had the most difficulty detecting shapes and movement. He crossed the rail fence with an effortless hop, falling a mere twenty meters and landing in a silent crouch. He traveled the rocky flatland at top speed, unafraid of being spotted; after his earlier assessment of the guards he deemed them unskilled--nothing more was needed for keeping an eye on rowdy children and daredevils that may try to do as he was now.
The air thickened as he approached his destination and before he even felt the first tendrils of mist on his face, the foreignness of the altered atmosphere presented itself to his lungs. It burned, oddly freezing, as though he were at the top of a snow-capped mountain and the oxygen was too thin.
"Guess I should do it here," he muttered before coughing a couple of times. He tried to keep his breathing as steady as he could--it wouldn't do to start hyperventilating and lose control of his situation before it even began. De-shouldered his pack and knelt to the ground.
"Kuchiyose no jutsu!"
The subsequent plume of smoke dispersed into the heavy air, leaving a neon orange toad in its wake—the bright spots on its back visible through the dark of the night.
"Yo, Nii-ch--ack!--" the little toad broke down into a series of hacks and chokes, falling into the same predicament that Naruto wanted to avoid for himself. Naruto winced, wondering if he should have summoned a little farther from his current location.
"Sorry, sorry," he hushed, keeping his voice down in case it carried over to whatever guard may be on duty. "Just tell Fukasaku-sensei that I've arrived at the Anesidora Mists."
As an elder, Fukasaku had the ability to travel from Mount Myouboku to Konoha without a summoner. He could keep Tsunade informed for Naruto--though, from the looks of it, he may not be able to rely on summons if they required the same atmosphere as humans.
"I can't--" the toad gasped. It would not last much longer; apparently its smaller lungs were suffering much faster than Naruto’s own.
"I know," he rushed, feeling guiltier the longer the poor thing suffered. "Just tell Fukasaku so that there's some record of when I arrived. It will put Baa-chan at rest. You can go now."
The toad didn't leave. Instead its wide, blood-shot eyes swiveled between Naruto and the towering mists behind him.
"You--you're--," coughing ensued, followed by long, shuddering breaths.
It took Naruto only a moment to understand the toad’s concern.
"I'm not going in!" he lied with a strong assurance in his tenor. "This is just training at the edge. I'll be fine."
Unsurprisingly, the toad accepted this without suspicion, probably so desperate to leave it would willingly believe any security, and popped out of its summon. After all, one would have to be completely daft to even approach the mists from the safe point, let alone breach them. It must have figured that Naruto's stupidity ended here.
Naruto sighed, choking a little on the slightly toxic air, and picked up his pack. He had several hours until sunrise, but he wanted to get into the Mists far enough to be undetectable in the light.
He looked at the opaque, seemingly impenetrable wall. Though the sight was not welcoming, a compulsion called him forward--the same compulsion that choked him while he slept and pushed him away from Konoha. What he sought lay either in those mists or beyond them...if there even was a beyond. For all he knew this could lead him straight off the edge of a cliff only a few meters in.
Steeling himself for what lay ahead, Naruto gingerly drew upon the Kyuubi's chakra, feeling the malevolent heat spread from his belly to every peripheral limb.
Almost immediately he noticed the difference. The parasitic power that once made him cringe granted him an ironic relief. It still pained him to breathe, it still felt like he could not suck in enough air to satisfy himself, but he could survive. His body was adaptable—equipped to utilize whatever compounds this new air offered him in a way no human's could.
He continued several steps forwards at a slow and measured pace until he was completely submerged within the grounded clouds. He could no longer see the stars, and thus, no one could see him.
His face felt moist now that it was being caressed at all angles by the fog, and his body cooled through his clothes. He felt like he was moving through a heavy blanket of chilled steam. Which happened to hurt him when he breathed.
Before he could take another step he began experiencing sharp difficulty breathing again. He was close enough to his own land that the oxygen supply was still in the majority, but the presence of the new poison was enough to cause him suffering.
Naruto winced and focused on taking slow, even breaths. The Kyuubi made it easier--at least he was alive--but the more toxins he accumulated, the more he became aware of the foreign substance traveling through his body.
If he could only take several steps at a time before having to stop and wait for his body adjust--and he had a feeling the adjustment times could be long--then this may take longer than he expected.
Though the pain in his lungs increased with every step, the heaviness of his heart lessened. This was right. He knew it was right. Just like he knew Gaara could be saved and he knew Pain could be reasoned with. The pain would be worth it in the end; forcing evolution onto his body would be worth it.
He just needed patience, tolerance, and to always know which way was north.
Naruto's compass stopped working three days into his excursion.
He slept when he was tired and he used this as a means of keeping time. Night and day were indistinguishable. The mists were every bit as alive as the natural chakra, and appeared to emit a dim glow of their own, so he was not damned to total darkness
Luckily, a rock wall--undoubtedly the base of a mountain--served as his guide. He stuck to its side, only able to see about five feet in front of him before the air became too opaque.
There was something otherworldly about this land he traveled that kept from losing vigilance in an otherwise unstimulating environment. He encountered no plant life, no strange animals, just a stony ground and endless clouds. It was something in the air--the same air that tormented his lungs. Something...sentient.
Though more physically isolated than he had ever been in his life, Naruto never felt alone.
He spent much of his time sitting in meditation. His stomach muscles constantly, yet unconsciously, engaged. Sometimes he would do stretches or calisthenics when he felt well enough to, not only to keep in shape but also to prime his body more quickly to accept the air it was given. It would not do for him to be winded within a minute if he suddenly found himself in a situation where he needed to defend himself.
His limited movement meant fewer calories were needed, which worked out well for him as he did not pack much in the way of sustenance--mostly just water. He could live off the land when he had to, but he had yet to encounter anything to live off of, so it had been soldier pills and tasteless rations the whole way.
An increase in his appetite in the last couple of weeks certainly did not help matters. He had been ridiculously hungry, more so than usual, and often ate two to three times his usual amount. Tsunade-baa-chan said this was normal and he was in for another growth spurt. Naruto had to wonder if depriving his body of nutrients, air, and its usual activity would stunt his growth.
When he did eat, he ate slowly, forced to cater to his suffering body. Though his respiration was the most noticeably affected system, the rest of his body suffered too. Every cell in his being was constantly exposed to the Kyuubi's chakra (while it helped him in such cases, it always came with a price) as well as being force-fed the wrong nutrients. His brain was angry with him and his head always hurt. His arms and legs were unhappy about moving forward; his muscles wanted more oxygen than the Mists provided. Sometimes he could not keep food down, and he had an inkling it had something to do with an inability to produce lactic acid.
Everything was being rearranged--every function of every mechanic. Needless to say, pain became a constant for Naruto.
But this was right. This was so right. He knew his body would eventually learn to function normally again. He just needed enough time.
Using nature chakra made him feel better almost instantly; it did not provide much in the way of physical relief, but rather it connected him to the power that drew him here. He could feel it--a new presence that grew more prominent every day of travel--it reassured his every doubt. Its power was immense and just...everywhere. When he drew upon the natural chakra he could feel it change, move within him, as though alive. It was a part of the Earth--no--it was the Earth.
He did not know if he only could feel this because of his new location, because the strange and puzzling Anesidora Mists brought this forth, or because he had not had such extensive practice at meditating before.
It made his story about completing Sage training all that much more plausible. Perhaps there was more to those dreams and impulses than he originally thought. What if Jiraiya went through the same thing? Receiving dreams and harrowing urges that tore at his heart until he had not choice but to follow them. Was this meant to be the next step in sage training? Why had Fukasaku never said anything?
No, Jiraiya was purely human--or as pure as that man could get. Naruto managed this only because of the Kyuubi...because his curse gave him a personal advantage over anyone else who may have tried it before.
Regardless of the reason for his situation, Naruto spent more time in Sage mode than anything else. With the Kyuubi's inhuman capabilities, as well as the reassuring connection to nature, he could endure.
He physically felt the plodding change; every time it became easier to breathe he would stand up and continue to travel, slow steps and slow breaths. When the burning intensified he would stop, drop his pack, and return to meditation.
Physical pain he could handle, meditating for hours on end was tolerable, but he had a feeling keeping his sanity would be the hardest part.
Naruto did not know what day he was on when he first used his voice.
Beforehand, he had no reason to speak; all communication happened within his mind in self-doubting arguments. When traveling forward into an endless mass of clouds he often battled feelings of hopelessness with obligation. To see nothing but white, hear nothing but his own footsteps and labored breathing, never knowing if the path ahead led on infinitely, induced depressing thoughts.
Twice already, he had turned about face, not finding tangible significance in what he was doing. His body hurt all the time, he had yet to accept a satisfactory lungful of air, and the more he continued, the more he saw this as a fool's errand. Even the godly presence in the Earth could not reaffirm him.
But his instincts argued against his doubts, made his feet feel twice as heavy. He had to continue; after putting his body through so much strife all for unconfirmed visions, he could not turn back. Not after traveling at a snail's pace for miles. And it had to have been miles.
Currently, he moved forward after releasing all ambient chakra, testing his body unattached to the Earth. He became more aware of how little water he had left, how little food. Turning around was hardly an option; even if he could bring himself to do it, he doubted his body would accept its old food of nitrogen and oxygen and carbon. He was at an impasse; surviving within the mists was painful, but going on one side or the other would be just as bad. Not for the first time, he wondered what he had gotten himself into.
"I'm going to go insane," he uttered before stopping short.
It scared him for a moment--the sound of someone's voice, even if it was his own. His voice sounded different to his ears, grittier, either from lack of use or from the damage his body had to work under, and his throat became sore. He took a deep breath, his head pounding, and reminded himself that if he were anyone else he would have died a hundred times over by now. If he had not died yet, he probably never would. Not from these conditions, anyway.
Still, he at least liked to imagine that his body was finally coming to utilize this new air; he didn't want to spend the rest of his life suffering.
He continued walking, his steps a little stronger against his weak legs. The sounds of his footsteps echoed lightly and a leaf crunched underfoot.
Naruto stopped for the second time within a minute. He looked down, nearly afraid of what he would find (or not find), and lifted his sandaled foot. A yellowed, dried and cracked frond lay in pieces under the shadow of his leg. Heart swooping in excitement, Naruto pitched downward and touched it with the pads of his fingers.
Though it was dead, probably blown from its source for some distance, Naruto interpreted the meaning with triumph.
Life was nearby.