Tropes A to B (Adaptation-Induced Plot Hole, Arc Villain, Berserk Button, Beware the Silly One, Big Brother Instinct, Bowdlerise, Break the Cutie) | Tropes C to D (Call-Back, Chekhov's Gun, Cliffhanger, Combat Pragmatist, Crouching Moron, Hidden Badass, Curb-Stomp Battle, Dark and Troubled Past, Deconstructed Character Archetype) | Tropes E to F (Early Installment Weirdness, Famous Last Words, Foreshadowing) | Tropes G to J (Heart is an Awesome Power, Hypocrite) | Tropes K to M (Laser-Guided Karma, Logical Weakness, Mass "Oh, Crap!", Moral Myopia, Muscles Are Meaningless) | Tropes N to P (Nice Job Fixing It, Villain, Oh, Crap!, O.O.C. Is Serious Business) | Tropes Q to S (The Reveal, Shout-Out, Spanner in the Works, Superpower Lottery) | Tropes T to Z (Wham Episode, Wham Line)
Due to Eiichiro Oda's careful Worldbuilding and penchant to drop innocuous Chekhovs Guns which pay off massively and mostly taking hundreds of chapters, One Piece deals with a lot of The Reveals to seemingly insignificant people and events throughout the manga.
- Luffy gets into an eating contest with a random Boisterous Bruiser type guy at a bar, who later gives Luffy a pep speech in which he toasts to their shared ideals. Turns out that guy is Blackbeard, the evil pirate that Luffy's brother has been searching for, and several of the other men from around the town are really his crew members.
- Dragon, the man who saved Luffy from Smoker in Loguetown, is Luffy's father, Monkey D. Dragon, as well as the leader of the Revolutionary Army and the most wanted man in the world.
- Chapter 550 made another reveal. A reveal that doesn't make the plot take a new direction, but explained everything that has happened since Chapter 1. Portgas D. Ace is not Luffy's biological brother; he's the son of Gold Roger, the Pirate King.
- The true identities of Iceburg's would-be killers in Water 7 (the Straw Hats were initially framed for it): his secretary, two of his carpenters, and the local bartender, all of whom are actually professional government assassins.
- The reveal of what the ancient weapon mentioned in the Jaya Arc truly is in Chapter 649. It's Poseidon, a Mermaid who is capable of communicating with the Sea Kings, and who is actually Shirahoshi.
- Luffy's and Ace's other brother Sabo, whom they believed to have died during their childhood, is still alive and a member of the Revolutionary Army in Chapter 744.
- Chapter 763: Law's full name is Trafalgar D. Water Law, which more or less explains his intrigued but cryptic attitude and behavior towards Luffy since the very first time they met.
- Chapter 816: The Minks really were sheltering Raizo, and were lying to Jack to the whole time.
- A whole bunch in Chapters 817-820 thanks to the chapters being a huge Info Dump for the series' Myth Arc as a whole:
- Kin'emon is not actually Momonosuke's father, but merely one of his attendants; Momo is a lord of the Kozuki clan, allies of the Mink Tribe, and his father Oden travelled to Raftel with Gold Roger. Both Oden and Momonosuke were/are also capable of hearing the "Voice of All Things", like Roger and Luffy.
- Duke Dogstorm and Master Catviper traveled with Lord Oden after the latter left Wano: with Whitebeard originally, and then with Roger after the latter recruited Oden from the former's ship.
- Raftel can be found by using four "Road Poneglyphs" that each indicate a separate location, with Raftel being at the crosspoint of the four. One of the Road Poneglyphs is in the Mink Tribe's possession, Kaido and Big Mom each have one, and the fourth's location is unknown. What's more, the Kozuki clan is the group responsible for making the poneglyphs.
- The Sabaody Archipelago arc has a more comical one in the form of the Malevolent Masked Man Duval, who bears an intense grudge against Sanji for unknown reasons despite the two apparently having never met. When the mask comes off, the Straw Hat discover that Duval looks exactly like Sanji's poorly-drawn wanted poster, and is angry about all the unwanted attention he's gotten as a result.
- This is even done with certain characters' races. Among humans alone, they can be over 8 feet tall (and beyond, although not as huge as the shorter giants) and some are even born with horns, so they can sometimes throw viewers for a loop. Initially, we'd assume what race a character is from by their appearance and think nothing of it. Eventually, the narrative reveals their lineage through different means, such as demonstrating the distinctive traits of their respective races or just bringing it up in a simple conversation:
- Who would've guessed that Kokoro was a mermaid all along? She was walking around like any other human, but at one point, she had to save some of the Straw Hats from drowning. Cue her swimming through the water with a fishtail, in all her majestic glory. As a mermaid over the age of 30, Kokoro can split her fishtail into legs and walk around on land. It wasn't known to viewers, because she was wearing pants the entire time before the rescue.
- Bepo was originally thought to be a polar bear. It was odd enough that he could speak, so some thought it was because he ate a Devil Fruit, much like Chopper after eating the Human-Human Fruit. Many arcs later, it's revealed that he's one of the minks, a group of Beast Men based on all sorts of mammals (excluding humans, of course). Bepo just happens to be based on an animal that can stand on its hind legs like a human.
- Sanjuan Wolf is currently the largest character in One Piece. He's so damn huge that he was nearly the same size as Marine HQ at Marineford. Because he was always seen submerged in water, fans thought he might have been a gigantic Fish-man or merman. An official databook reveals he is a giant (AKA the same species as Dorry, Broggy, Jaguar D. Saul, etc.) and does indeed have legs. Not only that, Wolf ate a Devil Fruit that can make him grow even larger! This growth ability allows him to casually walk around on the ocean floor!
- Wadatsumi looks like a huge hairy giant. He was originally referred to as an umibōzu, a type of giant Youkai. Not only did Usopp think he was one, Wadatsumi's own crewmates just happen to jokingly call him that too. Eventually, he was revealed to be a tiger puffer Fish-man. By always drawing him with his fists clinched or fingers together, Oda was careful not to show the webbing between his fingers, which is a species-wide trait of the Fish-men. He also has a long dorsal fin extending from the top of his head to his lower back, but before his racial reveal, he was always drawn from a front view so that the fin wasn't visible. While Fish-men came in all sorts of colors, Wadatsumi stood out with a more human-like skin tone that nearly no other member of his race has. Lastly, his enormous size is very unique among his race, as they're usually taller than humans on average, but Wadatsumi not only dwarfs the regular giants, he even dwarfs the ancient giants, such as Oars and Little Oars Jr.! The only other character larger than him is the aforementioned Wolf with his growth ability.
- Pekoms was introduced as a strange lion man that could produce a turtle shell on his back. He states that it's due to having a Zoan Devil Fruit ability, so why is he a walking, talking lion? Like Bepo, he is also a mink. As though Oda knew how confused fans were about those two, he revealed they were minks around the same time.
- The giant children found in Punk Hazard were thought to be just that. The children of giants. However, we later find out that Caesar Clown was performing experiments on them, making them go through a gigantification process. Before that, they were just normal-sized human children.
- Ideo appears as a boxer with very peculiar shoulder pads stuffed underneath his sleeves. As it turns out, he's a part of the Longarm Tribe, known for having double elbows along with "midarms", segmenting said arms into 3 parts instead of 2 like standard humans. His seemingly elastic sleeves obscures his long arms. In his boxer stance, he was just elevating his upper arms over shoulder height, making them look like shoulder pads. With that, his midarms are held downwards, looking like regular upper arms, with his forearms positioned as normal.
- Dellinger has horns like a few other humans. Not a big deal, right? Well, they're the result of him being the son of a fighting fish Fish-man. Fish-men have always been based on real world marine life. However, the fighting fish seen in One Piece are a fictional species consisting of huge, crazed-looking fish with bull-like horns. There was no reason to think Oda would've created a Fish-man based on a fictional species. In addition, Dellinger's other parent was a human, so he's a Half-Human Hybrid. He also doesn't have webbing between his fingers, unlike full-blooded Fish-men. Lastly, he has a retractable dorsal fin that was hidden until he started fighting Blue Gilly and usually has human teeth, but can grow out much sharper ones when he's in Blood Knight mode.
- Kawamatsu introduces himself as a kappa shortly after making his on-screen appearance. This doesn't seem out of place in Wano, the Wutai of One Piece and this series was already full of several different races, so what's one more? However, he later reveals that he's a Fish-man. When he was a boy, he and his mother (who was a mermaid) faced discrimination in Wano. Before she died, Kawamatsu's mother told him to pretend to be a kappa in order to survive. It's also revealed that like Wadatsumi, he is also a tiger puffer Fish-man.
- Sanji's last name Vinsmoke, which is also the last name of a family of royals from North Blue.
- The World Government is actually ruled by an enigmatic individual named Imu, not the Five Elder Stars as advertised earlier.
- The Mole feeding Orochi and Kaido's forces regarding the alliance's activities is Kanjuro, who is actually a Kurozumi. After Kanjuro saw his parents get killed by vigilantes, Orochi got to him and convinced him to use his acting skills to infiltrate the Nine Red Scabbards.
- Luffy's Devil Fruit is actually an enigmatic Mythical Zoan Devil Fruit, Hito Hito no Mi, Model: Nika, a Devil Fruit of special interest to the World Government, as in, they have been searching it for 800 years, and failing to find it, reclassified the fruit to hide its connection to the Void Century.
- Pluton is currently stored beneath Mt. Fuji, and Sukiyaki explains that to make Pluton functional, opening the boundaries of Wano is required. Rather than merely undoing their isolationism, this requires draining the raised sea around Wano by destroying the mountain walls around the island.
- Vivi and her father Cobra's full name are revealed to be Nefertari D. Vivi and Nefertari D. Cobra.
