Time Braid

Time Braid is a Naruto fanfic that uses a Groundhog Day Loop device similar to that in Chunin Exam Day. The similarities end there.

It begins with a loop. Specifically, Sakura is looping. There are the usual time-loop issues before she decides to buckle down and get strong enough to actually pass the exam and (she thinks) end the loop. Things are going along fine until she runs into a looping version of Naruto, who apparently has his own loop in a parallel universe and crosses over with hers at long intervals. Then things go off the rails.

"Hidan: You'll run out of chakra soon, but Jashin won't. He's a god, but you're just a fancy medic-nin. Sakura: You know, I've been telling myself that for years. But as long as my Heaven Seal is active I can't fool myself. I see too much, and I can't miss the implications. I'm not just a medic-nin, Hidan. I'm the last native kami of this demon-haunted world, and my domains are insight and mystery. Not to mention that I just took about six levels of badass. Don't make me fight you, or you'll lose."
 * A God Am I: Pein, of course, as in canon. Notable for Sakura immediately laughing in his face that he's nowhere near as powerful as the looping Naruto. Then,, when she uses the Shiki Fuuin to bind the Kyuubi; due to her small portion of kami ancestry, she sacrifices only her human life, leaving her as a full kami living on borrowed time.
 * And I Must Scream: Hidan in the final battle.
 * Ax Crazy: Hinata (both the original looping version and Sakura's), the looping version after going insane living in the loops for years on end alone, Sakura's due to her semi-brainwashing by demon!Sakura.
 * Badass Boast and World of Cardboard Speech: Sakura gets one to Hidan.

"Naruto: Sakura, you said yourself that you just got your mind run through a blender and had to put it back together alone. How am I supposed to know you got it right? Besides, wasn't that crazy demon bitch made of you? Sakura: (angrily) Yes, Naruto. The Sharingan curse copied off all the darkest parts of my soul and stitched them together to make a whole person, stuffed her full of demonic propaganda, and plugged her into an infinite source of black chakra that corrupts anything it touches. And what did she do? She tried to find love, punish injustice, and become stronger. Oh, I'm so ashamed."
 * Bad Future:, in which the Eye of the Moon Plan was successfully enacted and drove everyone insane; all the righteous people were killed, allowing the demons to take control of the world forever. Averting this is the reason why . Of course, he's under the just like everyone else, so it's going badly wrong.
 * Brainwashed: This is loop!Sasuke's modus operandi. Leading to (kind of)...
 * Brainwashed and Crazy: Sakura is never used as a main combatant against her allies, but loop!Hinata is.
 * Book Ends: There are at least three of those in the last chapter, related to Anko, Jiraya and Kakashi. Understandable, since it's the last loop (unless something goes wrong).
 * Chekhov's Gunman: . After the forced merge early on, it seems this aspect is gone, but then she's discovered in a kind of 'inactive aspects' area of Sakura's Mental World, and Sakura uses her to guard the box containing the memories she doesn't want Sasuke to see. Later,
 * The Chosen One:.
 * Goes a bit further than that:
 * Epic Fail: Some of Sakura's deaths due to the Groundhog Day Loop are pretty embarrassing. She, at one point, gets Naruto to teach her Kage Bunshin no Jutsu, believe that if an imbecile like him can do it, she'd have no problem..
 * Even Evil Has Standards: is horrified at what loop!Sasuke did to Sakura with the Tsukuyomi, more so because, since she just locked up Sakura with the same power, Sakura expects much the same from her.  comments that beating her into submission would be "way too much like raping myself repeatedly", and decides to resolve the conflict of which personality will be dominant by seeing who can make a better life in the loops.
 * Deliberately lampshaded later on, after their conflict has been resolved in Core!Sakura's favor:

"Kabuto: How? Sakura: I don't make villain speeches, Kabuto. You'll just have to die not knowing."
 * Face Palm of Doom: Rasengan manifested inside the brain. Regenerate that, Kabuto.
 * Foreshadowing: During Sakura's first apprenticeships with Anko, at one point she asks about brainwashing (in context, because of its superficial familiarity to the manipulation used with Anko's seduction techniques). Anko replies that the only reliable method of actual brainwashing that doesn't damage the victim into uselessness is pleasure-pain conditioning, but that's not much used because it requires a couple of days isolated with the victim. The astute will remember the duration of the Tsukuyomi genjutsu of the Mangekyo Sharingan. Guess who shows up a few loops later?
 * Future Me Scares Me: A variation occurs when during a loop at a Chunin exam, a normal not-yet-crazy Sasuke has everything explained to him and expresses horror when he hears what his looping self did to Sakura.
 * Genre Savvy:Played straight in the scene where Looping!Sakura wtfpwns Kabuto:

"Kyuubi: Sakura, you can't mean this! You're a goddess! All you have to do is say the right words and you'll be immortal! Let me go, and I'll tell you what they are. Sakura: We're not afraid to die, dumbass."
 * Heroic Sacrifice: Sakura binds the Kyuubi with Shiki Fuuin. It's noted specifically that she was quite capable of escaping to a parallel universe, but loop!Naruto and Hinata were prisoners in the Kyuubi's mind, and she would not leave them.

"Sakura: What did you expect? You're a misery demon. Your purpose is to spread suffering wherever you go. Whatever made you think your own life would be immune?"
 * Hoist by Her Own Petard: During the period of time Demon Sakura has control of their body, she spends several loops trying and failing to break her and her girlfriend Hinata out of the 'weakness' that is Konoha and forge kick-ass new lives for themselves. Her efforts result in Hinata's eternal (until Goddess!Sakura finally finds a loophole out of it at the end of the story) damnation, their deaths at the hand of the ANBU, and a failed loop. She tries several times and no matter what she does or how many of her earlier failures she compensates for, things just go even worse each time. Until Sakura is finally ready to regain control of her soul and explains where her demon aspect went wrong.

"Demon Sakura: Yes, demons can effect fate just by their presence, and the type of effect depends on our breed. But my aura of misery shouldn't affect me! That would be stupid. It just spreads over my enemies, and the mortals around me. Sakura: Like Hinata? Demon Sakura: No! Sakura: Yes. I can see it, you know. The dark power welling up from that thing you call the Nidhogg system. The way it flows through your half of our soul, shriveling everything it touches before leaking out into the world around us. The way you shape it to work your techniques, and the patterns it forms on its own when you aren't paying attention. You can never have a mortal lover for long, demon girl. Your own nature will destroy your happiness every time."
 * Played with shortly later on when Demon Sakura points out that allowing this would be a fundamental design error, and then Sakura pointing out she'd missed something:

"Sakura: ... okay, maybe I'm the runner-up. That's alright, I can live with being second to a guy that can knock out the damned Kyuubi."
 * In Spite of a Nail:.
 * Journey to the Center of the Mind: This is how mind-control techniques work--including, as it turns out, the Tsukuyomi. Sakura makes hers a maze of traps with the goal well hidden; Naruto's requires the user to fight the Kyuubi.
 * Mental World: Sakura has one. It's far more like a 'real' world than anyone else's, because . She ends up partitioning it five ways from next Sunday and trapping the hell out of the outside bit, as a defense against mental attacks.
 * Mugging the Monster: This happens a lot to Sakura and Hinata when they go undercover as nukenin. It's noted that after a few months of Sakura letting Hinata do what she wants to the attackers, there stop being so many of them.
 * Polyamory:.
 * Power Perversion Potential: Sakura's ability to make herself into older and bustier is used like this as well as Naruto's Shadow Clone Jutsu (useful for when you have more that one woman to please).
 * Split Personality: Sakura can divide herself into aspects, which embody different sides of her personality. The original 'Inner Sakura' is one of these.
 * Split Personality Takeover: An ill-considered decision activates a curse that makes a 'dark' aspect of Sakura, then turns it into a literal demon. This demon imprisons the original in her Mental World and goes about several loops controlling her, before Sakura takes a level (one of many) and forces a merge with her.
 * Super-Powered Evil Side: Sakura, kind of. Her is actually quite a bit less powerful than she is, but being a demon and hence related to its creators, she has all the powers of the Sharingan without needing to have committed the requisite mortal sins.
 * Take That: A few to Chunin Exam Day. Sakura has a "don't act like a psycho" rule, and she notes that going through a long series of loops stealing Sasuke's eyes each time would most definitely violate it.
 * Took a Level in Badass: The characters take advantage of the oodles of extra time at their disposal by training like mad. Sakura in particular goes to pretty much everyone she can think of (friend and foe) to learn new techniques, and even trades techniques with rival villages.
 * Unreliable Narrator: One of the most obvious ways in which Sakura matures is the way in which she views the people around her, and how that changes over time. Discussed by her and loop!Naruto in the end with regards to Kakashi.
 * Verbal Backspace: During the final battle, Sakura has been fuming for some time over a comment by loop!Sasuke that she is "not a frontline combatant". (Which isn't her specialty, but she's S-rank for a reason.) After a skirmish in which she, she is exulting to herself that "I am the champion of ass-kicking!" Then she looks over and notices Naruto's fight against three copies of himself with their will suppressed to release the Kyuubi entirely.

"Sakura: (thought balloon) Wait. Pure gold. (looks up at the Throne of the Gods hovering overhead) Hinata... can you help me get up there?"
 * Wham! Episode: Sakura sees.
 * Wham! Line: After the defeat of the final villain Naruto is out cold, Nice!Hinata is a powerless ghost who will pass on to her eternal damnation as soon as Looping!Sakura finally passes on, Sakura has sacrificed her mortality and is also a powerless ghost animated only by the last wisps of her divine gold chakra and doomed to pass on or perish from lack of ability to replenish chakra in maybe an hour or so, Looping!Hinata is the only person still alive and able to move, and in general things look about as bittersweet bleak ending as they can possibly get. And then everything turns around with two sentences.

"Hinata: It isn't a ploy, is it? You really do want me to be a part of this, even though something about it terrifies you. I'm sorry, Sakura. I wish you'd found me first. *64 Palms Trigram*"
 * And earlier on, after Sakura had spent a great deal of time and effort trying to broker a peace with Looping!Hinata, and having come to warn her about Looping!Sasuke's intent to brainwash the other loopers.


 * Who Wants to Live Forever?: Hidan's immortality is of this variant--relying on it too much in a fight will leave him crippled with the secondary damage, but he can never actually die. Sakura ends up
 * Why Don't You Just Shoot Him?: "I don't make villain speeches, Kabuto. You'll just have to die not knowing."