''[[http://www.fanfiction.net/s/9306947/1/Once-again Once again]]'' is a ''Manga/OnePiece'' time travel FanFiction written by [=TheVictor=]. A 7-year old Luffy is approached by his future self. It seems Luffy's entire crew died at the hands of Fleet Admiral Akainu right after defeating the Yonkou Kaidou. Luffy and his future self fuse together, making him both much stronger and much smarter as he repeats his adventure again, hoping to avoid the same fate as well as correct some mistakes.

Easily the longest ''OnePiece'' PeggySue FanFic in the entire fandom.

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!Examples

* AlmightyJanitor: How everyone see Luffy after he tells them about his brother[[spoiler:s "Blue Gentleman Sabo" and]] "Fire Fist Ace", his friend Shanks, his grandfather "Hero of the Marine" Garp. [[spoiler:Oh, and he gets to phone Whitebeard about the Blackbeard issue.]]
** [[spoiler:The funniest part is that the crew still doesn't know about Luffy's father.]]
* BerserkButton: Luffy is obscenely frightening when he's in a bad mood; while typically done when he has nightmares, he also lost his temper when Nami broke his armor. His crew is terrified of his temper in that form, but in Water 7, when Luffy catches up with Usopp and finds that he had been beaten up by the Franky Family, the sniper notes that that wrath was downright tame compared to his expression at that point.
* BewareTheNiceOnes: Luffy's typically the happy-go-lucky guy we all know and love, but if he's in a bad mood, he's so scary that he terrifies the living daylights out of ''his own crew.''
* [[RedEyesTakeWarning Black Arm, Take Warning]]: Luffy will sometimes lose control of his Armament Haki when sufficiently angered by something. [[spoiler: For example, Blackbeard's face.]]
* BunnyEarsLawyer: Luffy kept his memories -- meaning that until Robin joined, he was by far the most world-savvy member of the crew. And even with Robin he's still MrExposition. He's still a manchild, though.
* CliffHanger: Many of the chapters, but none more than Chapter 61, where the fic dead-ends smack in the middle of Enies Lobby. The fandom is still hoping that after one and a half years, Victor will come back and resume his work.
* ContinuityNod: Luffy ''still'' wants [[RunningGag a bronze statue.]]
* CrashIntoHello: When Luffy accidentally uses [[spoiler:Geppou]] for the first time, he ends up catapulting himself several dozens meters away…right into Robin's bosom.
* CurbStompBattle: Many, many, of Luffy's fights, which make sense, seeing as he's a Yonko-level pirate in the middle of East Blue and, eventually, Paradise, the first half of the Grand Line. His fight with Crocodile was the only major fight he's had that wasn't one, but it was still a little one-sided. [[spoiler:His fight with Mihawk doesn't count because it wasn't really a fight -- they stopped as soon as Luffy saw that Zoro was okay.]]
* DarkAndTroubledPast: Future Luffy, and Luffy himself after gaining his memories.
* DarkerAndEdgier: While still fun-filled, this fic deals with Luffy's knowledge of his crewmates', Sabo's and Ace's deaths, and how he will do whatever he can to protect them all. [[spoiler:He often gets nightmares about everyone dying, and you'd better not anger him when he's in a foul mood.]]
* DeadpanSnarker: Surprisingly, Luffy, although pretty much everyone get it at some point.
* DeadFic: It hasn't been updated since August of 2013, and nobody has heard from the author since then either.
* DeathGlare: Luffy has mastered Haoshoku Haki, but he hasn't used it very much in this fic. But he doesn't need to; even without Haki, the fire in his eyes is enough to intimidate most foes.
* TheDreaded: Thanks to his actions during the Alabasta civil war and a subsequent interview, the entire world now knows that Luffy defeated Crocodile, resulting in this.
* EvilLaugh: Predictably, several of the enemies get this, such as Crocodile, Enel, and Spandam. But in Chapter 60, Luffy also gets one when he considers [[spoiler:reviving Pluton himself]]…or at least that's what it seems like he's thinking.
* FlatWhat: How Luffy tends to react when the others (usually Sanji, Nami and Usopp) are stunned because he subverted IdiotHero.
* GroinAttack: In chapter 61, Luffy kicks [[spoiler: Spandam]] so hard in the crotch that even ''Lucci'' winces in sympathy.
** Enel also attempts one of these with Luffy. Well, it's a hit, but still harmless to him.
* HairTriggerTemper: Luffy has one of these on the rare occasions that he goes without sleep due to nightmares of his Dark And Troubled Past…or Future.
* IdiotHero: Aside from Robin and Zoro, ''everyone'' thinks Luffy is one. It's actually {{Subverted}}. He's childish and pretty much crazy, but he's quite smart and mature when he needs to be.
** In fact, he even takes advantage of this to piss off his enemies -- especially when he was stuck in that cage by Crocodile. By the time Vivi arrived, Crocodile was almost ready to tear his hair out because Luffy was annoying him so badly.
* JawDrop: Common, as you'd expect for anything involving One Piece. Notable is in Chapter 2, where he gets this twice from everyone in sight when he knocks out the bandits with Haoshoku Haki and one-shots Higuma.
* KickTheSonOfABitch: Luffy does this both literally and figuratively to [[spoiler:Spandam]]. It won't surprise anyone to learn that he greatly deserved it.
* LongRunner: There are many Peggy Sue fan fictions for One Piece, but even though this one has been a Dead Fic since August 2013, it remains the milestone for the other Fan Fictions in storyline progression (mid-Enies Lobby arc).
* {{Manchild}}: Luffy, since he's technically an adult mentally -- or at least as much as an adult that Luffy can be.
* MoodWhiplash: Luffy became quite skilled at this.
* OhNoNotAgain: Sanji gets a mental reaction like this in Chapter 24 when Luffy's in a bad mood again (the last time being in Chapter 13, at the Baratie). He's downright scared, and when the rest of the crew finds out that that's the case, they're scared too…for very good reason.
* OnlySaneMan: Robin seems to be the only one to understand Luffy is ''much'' smarter than he lets on, rather than an overpowered idiot with occasional bouts of common sense. That can be blamed on her general maturity and world-savviness. It also helps that while Luffy is physically seventeen, mentally he's around the same age as Robin, if not older, making it easier for Robin to connect with him.
* OutOfCharacter: Surprisingly averted. Despite Luffy being much more mature than in canon, he's still the Luffy we know for the most part -- except he's technically over thirty years old now.
* OfficialCouple: Luffy and Robin are set to become the main couple, but other than some bouts of ShipTease, it really hasn't taken over the story…and the author has stated many times that that is the intention.
* PeggySue: Well, obviously.
* SetRightWhatOnceWentWrong: The very premise of the fic.
* SlasherSmile: Luffy gets something like this when he sends the rest of his crew, except Robin, off to hunt the South Bird as training…and punishment for insulting him.
** The next chapter also gives him one when he starts trying to kill Blackbeard.
* SparedByAdaptation: Sabo, [[spoiler:since the fic was started long before it was revealed that he was actually alive,]] and [[spoiler:Thatch.]]
* TheStationsOfTheCanon: Has this feel to it, though there ''are'' deviations -- chances are that the story won't really deviate noticeably until around the Whitebeard War Saga.
* SuperMode: For the most part averted. Oh sure, Luffy still has his gears, but he doesn't need to use them. Justified that he's a Yonko-level pirate in the middle of Paradise -- his baseline strength is probably equal to that of the upper tier Warlords.
* TookALevelInBadass: Luffy again, of course (in the alternate future, he managed to ''kill Akainu''. Too late to save anyone, and he wasn't conscious of his actions at the time, but still!), but the other Straw Hats also got stronger thanks to his training. [[spoiler:Sanji and Zoro can somewhat use Observation Haki by the end of the Skypiea arc.]]
** Also, Future Coby, who became an admiral and ate the "Toki Toki no Mi/Time-Time Fruit". Luffy resolves to make sure he makes it to that level of strength again.
** Luffy also gains higher bounties -- his first bounty is [[spoiler:70 million]] and his second one is [[spoiler:160 million]].
* TookALevelInJerkass: Justified with Luffy -- after seeing his friends dying in front of him, he's determined to make them strong enough to survive this time around, as well as getting stronger himself. [[spoiler:The recurring nightmares and subsequent lack of sleep doesn't help.]]
* {{Troll}}: Luffy certainly acts this way towards all his opponents (especially evident with Arlong and Crocodile; with the latter case, when he's locked in a sea prism stone cage, he annoys Crocodile so much that by the time Vivi arrives, he's able to shut up the Warlord's Evil Laughing by threatening to do another of his impressions), but even outside of that, he appears to get a kick out of pissing people off (such as with the White Berets in Skypiea). His strength, general maturity, and knowledge of the future allows him to get away with this.
* UnstoppableRage: If you bother Luffy when he's in a bad mood, you're in for a world of hurt. But if you harm one of his friends…you may as well dig your own grave.
* WillfullyWeak: Luffy deliberately refrains from using all of his abilities—most notably, his Haoshoku Haki—to make sure that his plan for setting right what once went wrong is not jeopardized by some higher-up antagonist finding out just how strong he is.