Summary: Faced with a destroyed world, the last two Jinchuuriki travel back in time to prevent the world's destruction, this time they will be prepared. FemNaru, Timetravel, AU, Pairings Undecided.

Disclaimer: I do not own Naruto.

Prologue: From the End of the World

A figure was kneeling on the smooth stone floor at the bottom of a gigantic crater, drawing lines and kanji with the grace and confidence of a master; her blond hair was kept out of the way in a short, spiky, fanned-ponytail, leaving long bangs framing her face, and she was wearing a black halter top and black shinobi pants, having long foregone protective gear as pointless.

She was Uzumaki Naruko, Jinchuuriki of Kurama the Kyuubi, former jonin of Konoha, and one of the only two survivors of the fourth shinobi war.

A muscular blond-haired, dark-skinned man sat a fair distance away in silence, a rarity for those who spent more than two seconds in his presence, but he dared not disturb his companion.

He was Killer B, Jinchuuriki of Gyuki the Hachibi, former jonin of Kumo, and the only other survivor.

Many think fuinjutsu is a simple matter of copying some designs, that so long as one has a picture reference and decent calligraphy, one can replicate even the work of masters, and that making seals is just a matter of fitting pieces like a jigsaw; it is not uncommon for shinobi seeking an edge to delve into the art of seals thinking this, and be quickly proven wrong, barely a handful delve further, and even less succeed.

In order to make a seal, the user needs to combine his or her own blood with the ink, the larger the proportion of blood vs ink, and the higher the potency of the user's chakra, the more power one can put into a seal, making stronger and more complex seals possible.

While anyone with enough chakra can replicate the simpler seal designs, as more power is used, the pre-made designs become more inefficient until they either backfire or stop working, what separates the dabblers from the true users of the art is the ability to adjust to this, to change or even create new designs to counter this and take advantage of the extra chakra, designs that are as unique for each individual as their blood and chakra used in the seal. The mark of a master is the ability to both understand and design complex seals, seals that are mostly made with blood.

What Uzumaki Naruko was doing now was definitely the work of a master, possibly the greatest masterpiece of fuinjutsu ever since the sealing of the Juubi.

It was risky, it was stupid, the likelihood of success was grim.

It was better than living in an empty wasteland.

When the five great shinobi villages allied themselves against the common threat of Akatsuki, the Madara impersonator used his skills at manipulation and outright control through his sharingan to bring many of the lesser villages to his side, and bolstered with his army of white Zetsu clones he dragged the world into five years of bloody war; it only got worse after Kabuto joined after the first year, digging deep into Orochimaru's experiments and releasing horror after horror into the field.

Even then, the Allied Shinobi Forces persevered, and at last managed to corner the two madmen in the Mountain's Graveyard, intent on at least destroying the source of the Zetsu army, and using the presence of the two remaining Jinchuuriki in one place to lure Tobi out and hopefully end the war once and for all.

When the Allied Shinobi Forces managed to stop both the Zetsu and the Edo Tensei army, and the two demon containers proved to be too problematic, Tobi grew impatient, and decided to hurry the plan and re-create the Juubi using only a small piece of the eight and nine tails, and while everything appeared to be according to plan, as soon as it was ordered to use a Bijuudama the imperfect Juubi proved to be unstable and exploded.

The explosion, while killing all but two of the shinobi present and leaving the biggest crater in the elemental countries, wasn't the problem; the shockwave of primordial energy that disrupted all chakra it touched and killed every lifeform as far as Naruko and Killer B have managed to check, was.

Every lifeform but the two protected by their respective Bijuu, that is.

That was four years ago, four years of looking for any sign of life, four years of scavenging the ruins of temples and ninja villages for a miracle, four years of preserved food and ration bars.

Luckily for the two Jinchuuriki, the Allied Shinobi Forces had stockpiled on the later two, there was nobody to guard their targets, and all chakra-based defenses were down.

Naruko was already a master of fuinjutsu by the end of the war, she had even made a headway on space-time techniques, but there was a big difference between even the biggest accomplishment of the field ever recorded and what she was attempting today.

"It's done."

Wiping the sweat of her forehead, she stood and stretched, purple slitted eyes gazed at her work; it was nearly noon, and it had taken her three days nonstop, her back and knees were killing her, her wrist was no better, and if it wasn't for Kurama, she would have bled to death in the process a dozen times; she felt pride at her work, grim determination to continue with their plan, and a sense of finality? peace? no matter if she succeeded or failed and died, she would not regret this.

There was also quite a bit of amusement, it was fitting that the greatest work of the last Uzumaki was a gigantic seal in the shape of a spiral.

"Finally!, all this silence was making me crazy yo!" B jumped into the center of the seal.

She nodded, more than used to his personality by this point, thirty handseals flashed at prodigious speed and the whole array lit up, the initial activation was done.

"You both know what to do," there was little else to say, and noon was upon them.

And so they stood, back to back with their hands as if praying and their chakra cloaks fully active, channeling the energy into the huge seal.

Here, in the epicenter of the explosion, her masterpiece would feed on the thick natural energies left by the Juubi and most of the chakra of the two strongest tailed beasts, open a portal through space and time, rip their minds and souls out of their bodies and send them 18 years back in time to join their respective past bodies, in a process eerily similar to how the chakra of a dispelling kage bunshin returns to the user along with its memories.

The winds picked up, whirling around the pair, their chakra cloaks dimming to almost nothing as the seal pulsed brighter each time, and in a final flash of light, they knew no more.

Author Notes:

This is a time travel story, but this is NOT a story where the traveler will closely follow the previous timeline to avoid disturbing it while trying to save everyone and their grandmothers and their family pets. Naruko WILL vary the timeline widely, and while she wants to stop the end of the world and to a lesser extent the war, she only really gives a damn about a handful of people.

As you can see, there are several changes compared to canon apart from the protagonist's gender, either because of changes on the protagonist or because they made more sense to me that way.

But instead of making my first chapter a huge summary, I'll reveal them slowly as the new timeline progresses.

Regarding characters, let's get the view I will be using in this story for a few of the main controversial ones out in the open:

Expect a very different skillset, personality, morals and goals from Naruko, she's cold and jaded, she is not a forgiving person, but she's likely to feel kinship towards outcasts; she wont have any bloodline other than the Uzumaki chakra potency / longevity, and *maybe* the chains, nor she will be a master of 80 elements and sub sub sub elements; on the other hand, she was a solid S-rank kunoichi even without resorting to the Kyuubi, and she will reach said height again and surpass it.

You can also expect a very different team 7 dynamic, she did not go out of her way to make a rivalry with Sasuke during the academy, and in the face of her competence and Sakura's own insecurities, the pink-haired fangirl will change her ways much earlier in both timelines.

Kakashi will be a good comrade, but a shitty sensei who doesn't know how to deal with kids, curiously, Naruko not being a mini-Minato with Obito's grin and personality will make things much easier for him than in canon.

The third can't help but blame her for his wife's death, despite rationally knowing it's wrong, thus, while he would harshly punish physical harm coming to her person, he can't bring himself to do more for her situation and upbringing than absolutely necessary.

Regarding pairings, I'm not confident enough in my skills at this point to write romance, tho I may pair some people in the background if it serves a purpose, still, even in the case this changes, this will NOT be a NaruSasu nor NaruHina, with Naruko's planned personality within this story, it'd simply not work.