Standard Disclaimer:

I do not own Naruto, Rurouni Kenshin, or any other series that may be used in this fic. They belong solely to the wonderful people that have written them. This is the result of spending too much time indoors during cold Alaska weather and watching too much anime.

Inheriting Insanity

A Naruto/Rurouni Kenshin Crossover

By SourdoughAK

Prologue - Insanity's Onset

"... Naruto... you were special... but I am more special than you."

These words resonated in the blond-haired Gennin's mind as the Chidori and the Rasengan clashed, the two forces of nature fighting desperately for alpha status. For Uzumaki Naruto, failure was not an option.

His teammate, Uchiha Sasuke, was the sole survivor of the Uchiha clan that was murdered by his older brother Itachi. Driven by his obsession to kill him, Sasuke's sole focus in life is to gain power, even if it meant selling his soul to the devil. Thus the two Gennins find themselves at the Valley of the End in a heated battle. With Sasuke powered by Orochimaru's curse seal at level two, and Naruto fueled by Kyuubi's seemingly endless chakra, the two push onward towards their goals. If Naruto fails in his task to retrieve Sasuke, he will be lost to the snake sennin, thus increasing his threat to Konoha and forever damning the Uchiha clan into darkness.

As the two attacks collided, the forces shrieked as they fought for victory, encasing the two young shinobi in a black pearl. A deafening roar was heard, followed by a blinding flash that bathed the two young ninja as their fight for dominance in an uphill battle came to a conclusion. For Sasuke, victory would mean that he would travel the path he chose, hopefully to gain the power he sought. For Naruto, it would mean that he would prove his nindo, complete his first A-class mission, and keep the promise he made to his teammate Haruno Sakura.

The roar subsided and the flash faded away from view, revealing the young avenger standing above a seemingly unconscious demon vessel. It seemed that all Naruto's efforts were in vain.

Sasuke bowed his head forward, allowing his hitae-ite to slip off of his forehead and onto the ground next to Naruto with a loud clatter. Glancing at it, he noticed that there was a scratch across it where the leaf emblem was. He had boasted confidently to Naruto during their last fight that he would not be able to even scratch his head. That fight, however, was cut short as Kakashi intervened the moment that the Chidori and the Rasengan would have clashed on the rooftop of the hospital. Sasuke forced himself to suppress a smirk. Just as he defeated Gaara during the Chuunin Exams and Haku on the bridge in Wave Country, Naruto had done what was deemed impossible. Throughout his time on Team Seven, Naruto had continuously beat the odds and come out on top.

As rain fell from the sky a violent muscle spasm in the shoulder forced Sasuke out of his thoughts as a wave of unbearable pain shot through him, penetrating the very fiber of his being and forced him to his knees. Bowing forward, he coughed dryly, a small amount of blood liberating itself from his body through his mouth. The action brought him down to face the unconscious Naruto, his eyes focusing on the dented and scuffed hitae-ite he wore. It showed significant signs of wear, seeing as it was at one time the hitae-ite of their Academy instructor Umino Iruka. Naruto wore the metal band religiously, treasuring the coming-of-age gift that was given to him by his father figure. To him, the steel emblem was more than a hunk of refined iron that protected his head from being imbedded by kunai, shuriken, and the like. It was a symbol of acknowledgment and acceptance bestowed upon him by the one most important figure to him in the world. Sasuke knew that Naruto was considered the scourge of Konoha, and for what reason he could not understand. However, he also had no doubt that despite this, because of Iruka Naruto fought for Konoha with all of his being for the one person he felt was worth protecting. Over time, the blonde-haired boy continued to gather those that became close to him, making him even more determined to prove his way and protect his home.

Sasuke was no exception, and he knew it. He knew that Naruto saw him as a friend, even as a brother. For this reason, among others, Naruto fought him to the greatest extent of his ability, intent on bringing him back to the Leaf.

The young avenger stood shakily, still gripping his right shoulder. Casting his gaze to the seemingly unconscious boy on the ground, his face was devoid of any emotion. He could not tell if he or Naruto had been crying or if either one of them was crying at this moment, however far-fetched the thought was for someone to cry while unconscious. The rain drew the heat away from his body, chilling him to the bone and making him as physically cold as he was feeling emotionally. With a grunt, he turned his back on Naruto, eyes cast on the ground in front of him with the intent of keeping himself steady while he made his journey to the Sound Nation. He knew that Naruto was not alone in the woods, and he was certain that no matter what the state of his companions were back-up was on the way. With that thought in mind, he slowly began to trudge away, his body protesting his every move. Nothing mattered now except getting to Orochimaru and avenging his clan.

Years from now, Sasuke would look on this event in his life as the greatest mistake of his life that he never got to make. For the first few years afterwards, he would snarl, brood, and throw fits over how he was denied his chance to become more powerful, but the event following the fight would come to be the one event that he would become the most grateful for happening, for as he was shuffling away, a voice stopped him dead in his tracks, his eyes widening with shock and disbelief.

"You bastard... stop..."

Slowly, and painfully, Sasuke pivoted around. He could not believe what he had just heard, and turning to find the source of the voice only made the situation even more unbelievable.

As he turned, he saw Naruto shakily standing, making an incredible effort to support himself on his own two feet. He was obviously exhausted as he was breathing heavily, swallowing large gulps of air. Slowly, as he steadied himself, his breathing became less labored, and he seemed to regain some strength as he was not wobbling as much where he stood. The rain continued to pour down on the two young shinobi, matting the blonde's hair to his head under the weight of the water it contained. The blonde shinobi's cerulean blue eyes bored into Sasuke, seemingly into the depths of his soul, causing the young avenger to flinch slightly. It was as if Naruto was not looking directly at him but through him, gazing directly to the core of his being.

Sasuke's shock didn't last very long. As he stared back, his disbelief gave way to anger. After all this effort, the Dobe was still standing? In reality, part of him was relieved that his teammate was still alive, but to be standing after the scale of physical exertion and chakra depletion they had just gone through was just asinine to the youngest Uchiha. What was the dead-last's secret? How could he manage such a feat?

"Damn it... what does it take to keep you down!" The onyx-eyed boy snarled at his opponent. The blonde boy only looked impassively at him, further agitating him.

"You know damn well as I do I'm a stamina freak, Uchiha... it'll take more than what you throw at me to keep me from getting back up."

Sasuke only scoffed at this.

"Whatever. I'm leaving. If you follow, I'll kill you for sure."

"I can't allow that, Sasuke... I have a promise to keep..."

It was at this comment that Sasuke lost his composure again, snapping at Naruto.

"Damn you! Why are you trying to deny my what's rightfully mine! You know why I'm doing this! Leave me the hell alone!"

"You're taking an easy out, Sasuke. Do you really think that Orochimaru would give you power that easily? Everything comes with a price..."

"It doesn't matter... all that matters is killing my brother. For that, I'm willing to sell my soul to the devil to gain the necessary power."

"I don't think you understand, Sasuke. I told why Orochimaru wants you! I had a little talk with one of his bitches before we fought, and it's not because he's feeling like giving away shit like some humanitarian..."

"Keh... You actually know how to use that word, let alone what it means?" sneered Sasuke.

"Listen, you bastard!" Naruto growled, quickly loosing his patience, "He wants the Sharingan! He'll train you for as long as he wants to, and as soon as he's happy with the results he'll knock your soul out and take your body! It's guaranteed death!"

"And as I told you... I don't care."

Silence washed uncomfortably over the two boys, the sound of the rain beating the landscape and the rushing of the waterfall drowned out by the intensity of the argument.

"Sasuke," Naruto started, "You have everything you could possibly want in Konoha... Kakashi-sensei's respect, Sakura-chan's love, and the praise of the entire village. Do you really want to throw it all away? It would be a slap in the face to your parents for them to know you are doing this. They wouldn't want you to do this!"

"And what would you know about it! Don't presume to know anything about me OR my family!

"Damn it, Sasuke! If you go through with this, you'll end up destroying so many lives! What your doing is going to turn out to be exactly like what your brother did!"

"DON'T YOU DARE COMPARE ME TO THAT BASTARD!" Sasuke roared, totally losing his composure at the mere thought of what Naruto had suggested.

"Eh... don't kid yourself. You think you've had it worse than me because I never had anything to lose? That's horse shit, Sasuke, plain and simple. Do you have any idea how it feels to be hated for something that isn't your fault? To be deemed guilty of crimes and sins you never committed?"

"What the hell are you talking about, moron?" demanded the avenger.

"You're so full of shit when you say you know hell," the blonde Gennin responded, foregoing an explanation of what he said, "You see how the villagers look at me. How they scorn my very existence despite the fact that I have fought to protect them with everything I have..."

Naruto leveled his gaze on Sasuke, his blue eyes piercing into the young avenger's onyx ones. Sasuke stared back, refusing to flinch under his scrutiny, but began to wonder when Naruto had become like this. He sounded so mature... so intelligent...

"And you... you are the pride and joy of the village! They love you, respect you... even cherish you! You have comrades that would fight alongside you and are fighting to keep you from making a terrible mistake! And yet you're willing to throw it all away for an empty promise of power and cling to your hate like a little kid would cling to his mother's leg for comfort!"

Sasuke twitched angrily. The analogy Naruto used had struck a nerve. Being called a child, however indirect it was, was NOT something that Sasuke appreciated. His patience was wearing terribly thin, and Sasuke suspected that Naruto was stalling for back-up to arrive. With his body as banged up as it was, the time lost talking to the blonde shinobi would definitely make his escape more difficult.

"Do you remember what Kakashi-sensei said when he passed us? After you and Sakura fed me when I was tied to the log?" Naruto asked.

Sasuke didn't respond.

"He said that shinobi that don't follow the rules are trash, but those that turn their backs on their comrades are lower than trash (1). We are you comrades, Sasuke. Neji, Kiba, Shikamaru, Chouji, Sakura-chan, Kakashi-sensei... and myself. And you're turning your back on us, forgetting all that you, me, Sakura-chan, and Kakashi-sensei have been through together as a team. You're blowing off the love and acceptance of an entire village. And you're turning your back on me and the others as we try to save you from a fate worse than death!"

A breeze shot through the area, chilling their already cold and soaked bodies to the bone. Their gazes hardened on each other. Internally, Sasuke was fuming, losing is patience with the blonde and growing increasingly angry at his lecture. How dare the dead-last presume to tell him that he was not a proper shinobi! He was stronger and more skilled than the blonde idiot. Friends, family, and lovers where only a liability to leave you vulnerable, and were best eliminated before they became a problem. Why couldn't he see that?

"Are you calling me trash, Dobe?" Sasuke growled dangerously, daring him to prove his assumption right.

Naruto's brows furrowed angrily. He had fought the last Uchiha with all of his might, and had lost the battle of the forces. However, some unknown strength, seeming to come out of nowhere, forced him back into consciousness. As he spoke to the young Uchiha, he felt his strength returning to him, bit by bit. He could now keep himself steady without much effort, and his labored breathing eased to a normal pattern. For some reason, he could see each and every raindrop as they fell from the sky in front of him. He could feel the cold and gentle splash against his skin as if they were nails driving into his flesh. He could smell the mildew that grew on the forest floor around them, amplified by the damp air and water absorption. And the waterfall seemed to roar louder than he remembered, bordering on deafening.

Naruto inwardly sighed. He had tried to reason with Sasuke the best he could, and all his arguments were falling on deaf ears. It would have been so easy to let him go and walk his path, but Naruto couldn't allow that. He had a mission to accomplish, and a promise to keep. Sasuke would come back with him, one way or another.

As all this was running through Naruto's mind, not even five seconds had passed in silence. Finally, the blonde broke the silence.

"You are worse than trash, Sasuke... you are scum. You are exactly like Orochimaru... and you are exactly like your brother, you self-centered piece of shit."

The last comment was more than Sasuke could take, as his rage boiled over and his anger took control of him.

"How dare you..." He snarled before breaking into a full roar, "HOW DARE YOU! YOU SON OF A BITCH! I'LL FUCKING KILL YOU!"

And with that, Sasuke charged Naruto, ignoring the screams of protest his body was giving him. To him, his weakened state from the curse seal and his chakra depletion did not matter. Rage and adrenaline surged through his body, fueling him with new energy. His mind had one focus: to crush the insect that stood before him.

Sasuke delivered a devastating blow with his right fist to Naruto's temple, followed by an onslaught of jabs and straights to his midsection. They weren't nearly as powerful as they would have been with him at full power, but the anger and adrenaline rush put enough force behind them to allow him to satisfactorily start cracking the blonde's ribs. Sasuke followed this up with a spinning heel to Naruto's head, snapping it away with extreme force and causing the blonde to stagger. He continued with a straight kick into Naruto's stomach, and followed with combination of straights and jabs before ending with an uppercut that snapped his head back. The blow had enough strength to push Naruto back three, maybe four feet, spattering the lower leg of his pants with mud as he slid along the wet ground before coming to a halt.

Throughout all of this, Naruto had stood his ground, never falling. No matter what Sasuke threw at him, Naruto was firmly rooted. He never gave any recognition of being hit, nor did he even seem to register the pain. When the onslaught ended, he stood just as strongly as he did before. The only difference was that he was slightly slumped, as if his whole world came crashing down on him. His head was bowed, not allowing Sasuke to see his eyes or face, and thus creating an effective mask that could not be penetrated.

This sent Sasuke over the edge. He had hit the blonde gennin with everything he had, and he was STILL standing! It was utterly ridiculous!

"GOD DAMN YOU!" The onxy-eyed boy screamed in frustration, "GO DOWN AND STAY DOWN!"

Sasuke rushed Naruto again, intent on ending the confrontation. Putting all he could into his strength, he flew in with a right-handed hay maker, hoping that the attack would have enough power to knock Naruto down and keep him out of commission. Their distances narrowed to mere centimeters, and his blow came even closer to connecting. Finally, the loud pap of flesh hitting flesh was heard, and Sasuke was frozen dead in his tracks, eyes wide as dinner-plates and full of disbelief.

His blow never connected. Naruto had caught his arm at the wrist.

His shock was not short lived. Naruto emitted a low, feral growl before focusing his gaze on Sasuke. As he faced Sasuke, the wet sound of sinew snapping and crackling and tissue moving could be heard. Vein-like track lines formed on his face, starting between his blue eyes and spreading down his cherub-like cheeks and across his forehead to his temples. The sound continued to emit itself from Naruto's body, the rest of the formation of the lines hidden from view by the blonde's clothing. However, Sasuke knew that the lines appeared across the body. The formation of the lines on Naruto's flesh that was exposed through the hole in his jacket and on his hands were the only evidence he needed to make this inference. As these lines formed, Sasuke struggled against the blonde's grip, but to no avail. His hold was like the grip of a python latched to its prey.

However, it was Naruto's eyes that were the most unsettling aspect of his change. They did not change color as they did earlier in their conflict, nor did they gain the slitted pupil they had while they fought. They remained his usual cerulean blue, and emotions that the gaze held were to be expected. Sadness and betrayal were obviously evident in his eyes, as they were evident throughout their battle.

It was the level of anger that they reflected that was most unsettling. It was like staring into the face of a madman, his rage festering like a infected boil waiting to burst. Naruto seemed to be on the edge of sanity, teetering dangerously close to snapping completely and flying into a murderous rage.

It was then that Nartuo's growling voice brought Sasuke out of his stupor.

"You lousy piece of shit... you are coming back to Konoha..."

And with that, Naruto's right fist flew into Sasuke's humerus, snapping it like a twig. Sasuke felt the bone snap abruptly, feeling his arm become numb for an instant before a wave of sheer pain shot across it, forcing a scream out of him.

"... ONE WAY OR ANOTHER!"

Sasuke never got the chance to back away from Naruto. With his left hand still firmly clamped onto the wrist of his broken arm, Naruto lashed out again with a solid kick to Sasuke's thigh. His sudden, newfound strength displayed itself once again, as the kick broke the leg as if it were rotten lumber. Once again, Sasuke shrieked in pain. The leg gave out, and he slumped down, unable to support his weight. His rage and adrenaline rush had subsided, and now all he could feel was the pain. With the level of exhaustion he now experienced, his previous condition compounded by the anger and adrenaline fueled attacks he made, he was in no condition to react. Naruto then hauled Sasuke up to his eye level by his broken arm, causing him to grunt painfully, yet again leveling his gaze at him.

The rage held in Naruto's eyes, along with the odd track marks that covered his face, made the blonde look absolutely sinister. Just briefly, Sasuke felt a small twinge of fear in the back of his mind.

"Endgame, bitch." Naruto spoke coldly before hauling back and slamming his fist into Sasuke's gut, releasing his wrist in the process. The blow lifted Sasuke into the air, knocking his breath out of him. The onyx-eyed avenger coughed heavily, spitting up a gob of blood. Finally, Naruto brought his other fist down on his teammate to the back of the head, driving him into the wet ground. Sasuke landed with a hard thud, and did not move.

As Naruto stared coldly at the fallen avenger, his enhanced senses picked up the sound of his ragged breathing and the expansion of his chest through the rise and fall of his back and sides. Sasuke was alive, and although at this point he could have cared less if he lived or died, he preferred the outcome the way it was. The blonde gennin smirked to himself, knowing that his mission was complete. Now all that was left was to get the last Uchiha home.

It was then that a wave of nausea hit him like a ton of bricks, followed by a dizziness spell so bad that if felt like the world was spinning around him. Needle-like pain coursed through his body in waves, as if his nerves were conducting solely his pain receptors to his brain and doing it all at once. Naruto staggered a bit, losing his equilibrium before vomiting blood and falling to his back. The track lines on his body recessed, his appearance returning to normal, and darkness once again washed over him.

Deep within Naruto's mindscape, serious changes were occurring. The "corridor" that held the Kyuubi at bay shook with utter violence, as if it was going to cave in.. Inside his cage, the nine-tailed beast could only sit and ride it out. However, a sense of dread and foreboding overtook the creature.

What the hell is going on? He thought to himself, and why do I feel like I'm not going to like the answer?

Just as soon as that thought echoed into his mind, the mindscape shook violently as beige root-like protrusions tore up from the "ground" in front of him, uprooting themselves in an alarmingly increasing rate. They continued to approach him, and in a sudden burst of speed, penetrated the cage that held him and pierced into his body, firmly rooting themselves into him. Just as soon as the root-like structures buried themselves into him, they began heavy cycling of chakra to and from the demon. The fox could feel it's chakra drain from him, while the energy that cycled to him felt nothing like his or his vessel's chakra. Soon waves of pain coursed through every fiber of the beast.

Inside the body of Uzumaki Naruto, the beast screamed, and no one heard it's cries.

End prologue...

Author's notes:

This took longer than I expected. I started this fic sometime during my Christmas break, and here I am finishing up this part during my spring break. This chapter was originally longer than what I have presented to you, but upon finishing it my beta reader and I decided it would probably be best to split the chapter. So instead of one large chapter you folks get a one mid-sized chapter and one long chapter.

I plan on attempting some romance in this story, but I haven't decided on any pairings for this story yet. I'm a huge fan of the NaruHina pairing, so that most likely will be one of the primary couplings I will have. Also, I plan on using at least a couple of characters in interesting ways. I'll just have to decide as I'm writing

Until then, I bid you all good reading.

1) I know I probably totally butchered this saying. However, I like the way it came out, and it keeps the original feel of what Kakashi originally said.

Feel free to e-mail and review. Constructive criticism is nice, but flames will quickly be ignored.