According to legend, the ancient, simple child's toy known as the yo-yo took on use as a combat weapon in the hands of Filipino tribesmen centuries ago.note Whether it's true or not, if you see a yo-yo in a series with combat, particularly in an anime or video game and particularly in the hands of a young child, it's a safe bet that it will be slung with deadly intent and accuracy.
The legend may stem partially from the fact that as a weapon, the yo-yo bears a resemblance to a few hunting tools and weapons such as the Chinese meteor-hammer, the Argentinian bolas, and the maritime slungshot. The mundane yo-yo makes a cute and fancy stand-in for these types of weapons. It's also no joke that some yo-yo toys, from the traditional Chinese yo-yo to modern metal, weighted ones, can cause serious injuries purely by accident. Even the small plastic modern yo-yos, in the hands of a small child, can, and sometimes will, cause major harm to anyone and anything in the yo-yo's vicinity without the need of any magic or special training at all.
A type of Epic Flail. See also Brats with Slingshots and Improbable Weapon User. Compare Battle Tops. Your Killer Yoyo is likely to be wielded by a Badass Adorable or a Little Miss Badass, if the writer is playing up the "deadly yet cute" aspect of this trope.
Examples:
- Aldnoah.Zero: Barouhcruz carries a pair of razor-sharp, spinning discs on his Martian Kataphrakt, the Octantis. The wires on which the "yo-yos" are mounted can easily cut through a Terran Aerion with little effort, and the Octantis can also block shots by spinning around at high speed.
- Ayakashi Triangle: Among many Reo's many gadgets is her Chain Top, an extremely durable yo-yo with a chain instead of a string.
- Bakuen Campus Guardress: One of the characters fights with a kendama.
- Best Student Council: Nanaho Kinjo.
- B.Ichi: Nofix uses this as a weapon. His power as the King of Spin allows him to accelerate its rotation, making it all the more deadly.
- Bleach: Cirucci Thunderwitch wields a huge yoyo-like weapon in its unreleased shape.
- Combattler V: One of the first and most well-known examples in anime is the Choudenji Yoyo (Super Electromagnetic Yo-Yo), the signature weapon of the titular Super Robot. Humorously, it was inspired when the group and Professor Yotsuya saw a yoyo champion performing on TV.
- Fist of the North Star: Mamiya uses a yo-yo that suddenly produces blades in mid-air, which makes her a competent normal human fighter, but still nowhere near as strong as martial arts practitioners.
- Fushigi Yuugi: The Ryuuseisui-wielding Suboshi is the resident Psycho Yoyo Boy. He doesn't use an actual yoyo, but it counts.
- GUN×SWORD: Carmen 99 uses a bladed yo-yo.
- Hunter × Hunter: When Killua uses weapons, super-yo-yos on wires are his preferred choice; he's shown knocking chunks out of trees with them (he's super-strong, and the things weigh 40 kilograms each).
- Machine Robo Rescue: Ninja Mama is a Captain Ersatz of the Saki/Yoko archetype, complete with Killer Yoyo.
- Magical Girl Site: Sarina's yoyo has an Absurdly Sharp Blade that is capable of cutting just about anything it comes in contact with; at one point, it's used to cut a man in half vertically. Ouch.
- Marginal Prince: Sylvain Clark uses a yoyo to fight off bad guys during the last episode. He tends to fanboy over it in an earlier episode, as it is some merchandise from his favourite anime.
- Mobile Suit Crossbone Gundam has the Quavarze, which uses a beam saw mounted on the end of a "chain" of whip-like segments; again, not exactly a yoyo, but close enough.
- Powerpuff Girls Z: Momoko Akatsutsumi/Hyper Blossom's weapon of choice.
- Reborn! (2004): Chikusa Kakimoto wields a pair of metal yo-yos that shoot poisonous needles.
- Rosario + Vampire: Akashiya Moka flings a yo-yo at a Tengu-masked thug during their field trip to the human world in season 2. The yo-yo cracks the mask in half to reveal a face that is nearly identical.
- Science Ninja Team Gatchaman: Jun wields these. Of course, hers explode, so their effectiveness as a weapon is never in doubt.
- Spider Riders: Princess Sparkle literally kicked Grasshop's butt with hers, several dozen times.
- Sukeban Deka: Saki Asamiya was armed with a special metal yo-yo, which became her signature weapon — so much so that it's an integral element in the logo for the 2006 Live-Action Adaptation (now available in the United States under the title Yo-Yo Girl Cop).
- Super Doll★Licca-chan uses these in one of her forms.
- Symphogear: Shirabe adds these to her gear’s repertoire in season 3. They have lasers for strings and, like most of her arsenal, can turn into giant circular saws at will.
- Tales of Symphonia: Genis uses a kendama as a weapon seriously. Understandably, he's a magic-user, but still...
- To be fair, there's a series of skits dedicated to just how improbable it is.
- Tenchi Muyo!: Kiyone Makibi.
- Yu-Gi-Oh!: One storyline in the early manga (and Season 0 of the anime) features an entire gang of yo-yo-wielding thugs, led by one of Jounouchi's/Joey's middle school rivals. When Yami Yugi uses one against them, he's so good with it he brought down the roof of a shed!
- In the anime, one of the yo-yos even has spikes.
- YuYu Hakusho features Rinku, a child demon who uses psychically controlled yo-yos as his favored weapon. When he's first seen, he has them on each of his fingers. By the time of the Makai Tournament, he has them on his toes, too.
- Zatch Bell!: Victoream and Belgim E.O. both have spells that turn their arms into killer yo-yos, while Zeon can generate one made of lightning. Victoream's and Zeon's both have spiked rims, making them act like buzzsaws while they're moving.
- The Astro City sidekick Bravo wielded bolas in combat, using them as both melee and thrown weapons.
- Batman: The Joker once pulls one of these in a fight and is ridiculed for using such a cliched weapon. The intended victim asks him "let me guess, it's really heavy or it explodes or shoots acid or something?" Joker proceeds to unwind the cord of the perfectly normal yo-yo and strangle the guy with it.
- Daredevil:
- The Jester wields a weighted yo-yo as a weapon.
- In his origin story, a young Bullseye is shown throwing a yo-yo and killing a bird with it.
- The Flash: The Trickster has included yo-yos in his arsenal. While under the Top's influence, his near-obsessive use of the yo-yo (commented on by one of the G-Men) is probably also a tell for the normally playful James being buried under the stern, serious Agent Jesse, possibly as a bit of a slip in Top's mind screw.
- In Flashpoint (DC Comics), the Alternate Universe Joker's sidekick, Yo-Yo, uses a pair of these when fighting against Batman. In the animated adaptation, her yoyos glow yellow and pink.
- An issue tying into the Justice League cartoon has Speedy playing with a yo-yo in the Watchtower; he's able to hold off the villain at one point using it.
- Frank Einstein, the eponymous Madman, uses a lead weighted yo-yo among other toy-based weapons.
- In the Norwegian fantasy series Miranda, the eponymous heroine wields a so-called "coil" with great success — it is easily hidden, and nobody expects it from such a pretty girl.
- The villain of one special issue of The Punisher wields one and makes a reference to the aforementioned Filipino arts.
- The Simpsons #131 features a manga-styled segment. Lisa appears at the end, wielding two yo-yos and sporting understandably Super Saiyan-like hair. Pretty much a general Shout-Out to Sukeban Deka.
- We have, well, YoYo Man, who, true to his name, will sometimes wield a yoyo in battle. He also has that name since his series aired on a channel called EBC Yoyo, of which he is the mascot.
- In Avengers Grimm, Rapunzel has turned her ridiculously long hair into a meteor hammer by braiding it and tying a steel ball to the end.
- A character is attacked with a yo-yo, among other things, in Child's Play 3.
- Egor in the Day Watch movie is seen playing with a YoYo like object. It turns out to be a magical weapon. The user flings it like a YoYo but upon impact, the object shatters into hundreds of pellets that continue attacking the target, do not suffer any loss of momentum and can multiply themselves by shattering as well. Needless to say it goes out of control and eventually wipes out Moscow.
- Duel With The Devils has the protagonist fighting a katana-wielding enemy with a yoyo. And winning. To be fair, the yoyo in question is made of Razor Floss.
- Master of the Flying Guillotine features a yoyo/hat-like device attached to a string that, as you can imagine, acts like a guillotine when it lands.
- In Octopussy, James Bond is attacked by a gang of Indian thugs who have been hired to kill him. One of them wields a yo-yo buzzsaw.
- The bladed lug wrench is upgraded to this when some rope is attached to it at the end of Sorority Row.
- While it doesn't kill, Michelangelo knocks out several hooligans with a yo-yo at the beginning of Teenage Mutant Ninja Turtles II: The Secret of the Ooze.
- Winner Takes All, a 1982 martial arts spoof film, have the hero being ambushed by various ninjas near the finale. The hero whips out a pair of yo-yos and wipes out all the ninjas in one fight scene. There's even a moment where the lead ninja, who uses dual nunchucks goes into a weapon-posing contest with the hero.
- Obviously, Yo Yo Girl Cop is based on this trope.
- Hansel (He is so hot right now!) in Zoolander uses a yo-yo to disarm an opponent
- Subverted in the first Alex Rider book: one of Alex's "gadgets" is a modified yo-yo. He expects it to be weaponised somehow, but instead it has an extendable and extremely strong cord.
- In Anno Dracula 1999: Daikaiju, the police in the Bund, Tokyo's vampire Fantastic Ghetto, consists of girls in Powered Armor armed with monofiliment yo-yos, presumably in reference to the anime examples. (It is later mentioned that they are all named Saki.)
- The The Baroque Cycle by Neal Stephenson claims the Filipinos had bladed yo-yos, and gives one to the enigmatic Enoch Root.
- Cadderly Bonaduce, a character in the Forgotten Realms novel series The Cleric Quintet, uses a halfling "spindle disk" to great effect.
- They became even more effective when he
coated them infilled them with oil of impact... - Their original incarnation, before the aforementioned addition to their firepower, wasn't all that strong and effective, as they were made from rock crystal. (In fact, Cadderly was aware of that from the start — he simply pulled an Ain't No Rule to have his toy classified as a 'weapon' for training purposes, being more interested in tinkering and occasionally fooling around than actual fighting at the time.) However, when Ivan makes him a new pair out of Adamantite, even he admits that they're a good weapon (while having to remove a piece of someone's face before giving them to Cadderly).
- They became even more effective when he
- In Elven Star, the second book of The Death Gate Cycle, a character uses a weapon called a "raztar" that appears to be a yo-yo with extendable razor blades.
- A brief passage in the final book of The Demonata describes a small girl using a yo-yo to fight off demons. No, really.
- The Marvel Comics novel Time's Arrow: The Present has Taskmaster attempting to decapitate Jean Grey with a yo-yo that has a monofilament string and an automatic circuit to ensure it constricts. He also takes the time to give a brief lecture on their use in the Philippines.
- Although not a textbook example of this trope, in 'Allo 'Allo!, General von Klinkerhoffen plots to assassinate Hitler with an exploding picture frame, detonated using a radio beam hidden inside a yo-yo. Unfortunately, the attempt misfires, and he blows up Herr Flick and von Smallhausen of the Gestapo, along with half of the men’s toilets at Nouvion Railway station.
- One of the entries in the Syfy channel's Face/Off makeup-F/X game show, submitted for a challenge to design an original horror movie character, used a yo-yo as a lethal weapon.
- The mooks who is known by the alias as "Yo Yo" in Healer has a yo-yo that has a rather sharp string, though it only comes into play when its wrapped around something like an arm and pulled. It has the benefit of being something counted as a toy even if it is only about as effective as you'd expect a weighted yo-yo to be and he prefers a gun when he can get away with it.
- In Kaitou Sentai Lupinranger VS Keisatsu Sentai Patranger, Trigger Machine Biker functions as one of the auxiliary arms for Pat Kaiser. Its front wheel can extend out on a long cable and not only deliver punishing blows, but can also grapple and launch enemies into the air to be finished off.
- In Kamen Rider Ryuki, Kamen Rider Verde wields a yo-yo.
- Power Rangers: Dino Thunder has Conner and his Battlizer armor, the main weapon of which is the Dragon Yo-Yo. A killer yo-yo made of fire. Silly, but it works.
- In Supergirl (2015), Toyman escapes from prison, killing three guards with a bladed yo-yo.
- Fabula Ultima: One of the Techno Fantasy sourcebook's sample custom weapons is the Combustion Yo-Yo. The game treats these combustion-powered yo-yos as a type of flail which deals fire damage and can be used to make two attacks per turn.
- An article in Pyramid magazine had a "Delinquent Schoolgirl Cop" archetype (an obvious homage to Sukeban Deka) for the Feng Shui role-playing game. One of the weapon choices available for the character was the combat yoyo.
- 1001 Science Fiction Weapons has a chapter on combat yo-yos. There is a complaint it's uncommon outside anime.
- The Adventures of Willy Beamish: A yo-yo is the weapon you finally beat the Big Bad with. Since you begin the game with it and only get to use it at the end, it also serves as a Chekhov's Gun.
- Bayonetta 3: Bayonetta obtains the Ignis Araneae Yo-Yo, which can open up to reveal spinning blades and is fire elemental.
- Bunny Must Die: The titular Bunny is another discus-style weapon wielder.
- Captain Rainbow: The titular washed-up superhero dual-wields yo-yos. No, really.
- Castlevania: A much more serious-looking variant, multiple titles feature animated suits of armor that wield large spinning spiked discs, usually known as "disc armor" or "discus armor".
- Chicken Little: The titular character uses a yoyo as his main weapon & even for grappling up ledges.
- Contra: Hard Corps: One of Browny's weapons is the "Super Electromagnetic Yo-yo". It's surprisingly powerful and one of the best weapons in the game, dealing heavy continuous damage on contact with enemies as well as homing in on them.
- EarthBound (1994): One of the ranged weapons is a yo-yo. It's practically useless, but all ranged weapons (except Jeff's best ones) suck in this game. Strangely enough, in his appearances in the Super Smash Bros. series, his yo-yo attacks are much more useful: in the first game, they do massive damage, and in Melee, can be used in a Ness-only glitch to make him virtually-untouchable.
- Justified, as Ness uses his PSI to manipulate the force and motion of the yo-yo (and his other weaponry).
- Ehrgeiz: "Yoyo Yoko" Koshibojin uses one in most of her attacks; hence the nickname.
- Einhänder: Gustav, the third boss has spinning disks connected by a chain on each shoulder that he can send out. They act like deadly razor yo-yos.
- Fly FF: One of the weapon sets available to Acrobats.
- Frak! for the BBC Micro starred a caveman armed with a yo-yo.
- The Goonies II: Mikey's primary weapon is a yo-yo, something never seen in the original film.
- Gaia Crusaders has an enemy mook (a guy in shades wearing a trench coat) who Dual Wield's spiked yo-yos to attack your players.
- Gotcha Force: Spinner Girl uses a spiked yo-yo.
- Guilty Gear: Bridget wields a yo-yo that can also turn into into weird and deadly contraptions as her weapon; this is likely part of the joke, as it goes nicely with the nun habit, in-line skates, and teddy bear. And giant handcuff belt-hula hoop thing which, according to one of her win animations, also doubles as a yo-yo holster.
- Hippodrome: The Final Boss is a giant taking up half the screen wielding a Killer Yo-Yo of Doom simply called "!@#$%!@!".
- Kingdom of Loathing: Enough yo-yo weapons exist to make its own weapon type. Examples range from the yo (a primitive yo-yo that does half damage) to the yohohoyo, a multi-elemental weapon wielded by the wacky pirate.
- The King of Fighters: Malin usually wields a knife, but also uses yo-yos (with or without blades) as well as electric batons and a giant hammer.
- In Kirby Super Star and Kirby Star Allies, one of Kirby's copy abilities is a yo-yo, taken from Gim. One of its attacks consists of breakdancing on top of the yo-yo (and a backward baseball cap).
- Kung Fu Chaos: Candi Roll wields twin yoyos.
- Legend of the Mystical Ninja: The best weapon in the game is the bladed "Yokohama Yo Yo". This yo-yo is not seen in any other Ganbare Goemon games, though the chain pipe serves a similar purpose as a long-range weapon.
- Lemegeton: One of the two styles of melee weapon available to Dawn, the "rotary knife" (actually more like a meteor hammer with blades attached), has yo-yo-like animations during some of its attacks.
- Mario & Luigi: Superstar Saga: The Yo Bro is an elite koopa like the Hammer Bro who wields yo-yos instead of hammers.
- Mega Man:
- Mega Man Battle Network 2 introduces the Yo-Yo chip. It deploys spinning blades from the disk as it's fired 3 panels ahead and deals double damage to any enemy in its way and triple damage to the enemy on the third panel and stuns the enemy instead of making them flinch allowing Mega Man to attack again. They also count as sword chips, making them useful against the Shadow viruses.
- The Spinning Blade from Mega Man X3 becomes this when charged.
- Mega Man Unlimited: Yo-yo Man's weapon, the Yo-yo Cutter. When Mega Man uses it, it fires out a yo-yo that can be aimed and can also move along the floor and walls before returning to him.
- Mother 3 has the "Friend's Yoyo" as an optional weapon. It's actually quite powerful, raises speed, and can be given to any of the party members except for Boney. It's all but stated that the Friend's Yoyo used to belong to Ness, and Porky keeps it well guarded. Hmmm.... And then on Tanetane Island, you can buy a Spiky Weapon, which is basically a yo-yo, with spikes.
- Neopets: The "Yo-yo of Death" is one of many Battledome weapons that only appeared in the Hidden Tower, which houses the best and most expensive items in the game and only allows one purchase per customer per day. Unfortunately, it's not a particularly effective weapon; it has a low chance of dealing spectacular damage, but that's about it. It's since been retired.
- Nightmare Ned: The protagonist uses one as a tool more than a weapon.
- Persona 5 Strikers: Sophia/Sophie wields one in each hand and uses them gracefully.
- The Paldean Pokémon Floragato uses its hardened flower bud in this way, using a vine as the string.
- Psychonauts 2: One of Raz's fellow interns, Adam, wields a yo-yo enhanced by his psychic powers.
- Rogue Galaxy: One of Jupis Tooki McGanel's special attacks is Yo-Yo Shock, where he swings an electrified yo-yo in a circular arc to damage all enemies.
- Rumble! @ the Campus: Megumi Taktsuki, though one of the prototypes shows Kiyo wielding one.
- Rygar: A massive, bladed yo-yo called a "Diskarmer" is the signature weapon of the series.
- Samurai Warriors 3: Hanbei Takenaka wields a giant bladed yo-yo that he also uses as a one-man helicopter.
- Similarly, Bao Sanniang from Dynasty Warriors 7.
- Sengoku Basara: Sarutobi Sasuke uses two of these as his weapons. Kasuga and Kotaro originally used these due to being character clones, but were later given weapons of their own.
- Shatterhand: The Yobobot flings a large white ball around itself.
- Spinmaster had yo-yos as the player characters' main weapon.
- Mike Jones' primary weapon in StarTropics is a yo-yo. You upgrade the weapon as the game progresses, as well as a bola weapon.
- Superfrog: The titular character can fight enemies with a yo-yo, however, it only works against flying enemies.
- Super Heroine Chronicle: Meru's primary weapons include yo-yos.
- Super Robot Wars: The R-2 wields a Beam Chakram attached to a cable. The Huckebein Mk II also has an exploding one as a weapon.
- Tales of Vesperia: Rita gets a yoyo as a weapon.
- One of the weapons in the game adaptation of TaleSpin was a yo-yo.
- Terraria: Yo-yos are part of the melee class, and a legitimately viable sub-category. They are thrown out to attack and follow the mouse for a set period of time, do continuous damage as long as they make contact with an enemy, then retract. They can be difficult to master, not so much for lacking damage but because of poor crowd control and knockback; the fact that they follow the mouse allows the player to attack from behind cover, making for easy but cheesy strategies. They also have accessories that can increase their length, launch out a counterweight (or several), and even send out a second yo-yo. Further along in the game, powerful yo-yos don't retract unless you release the button and some even spawn separate projectiles.
- Time Commando: A mid-90s third-person fighter/shooter that had a weaponized yoyo in the 'future' levels.
- Tomato Adventure: The first weapon the player character DeMille receives is a mechanized yoyo with a gear where the yoyo would be, simply called the "Gear Yoyo".
- Cathy from Top Hunter: Roddy & Cathy uses her yo-yo as a ranged weapon until she gets hold of firearms. Meanwhile Roddy uses fists from Extendable Arms.
- Toy Story: The game version fills Sid's room with spiked yo-yos hanging from the ceiling.
- Viewtiful Joe: Captain Blue Jr.
- Watch_Dogs 2: The protagonist's melee weapon of choice is an 8-Ball attached to a rope that he uses in a fashion similar to this.
- Yo! Noid: Domino's Pizza's commercials had a character called the Pizza Noid. In one of the games featuring him, he was the protagonist and his primary weapon was a yo-yo.
- Lightning Sentai Blitzenger: Kimura Sanjou, aka Jade Lightning, the youngest and most immature member of the team, uses a superpowered yo-yo as his weapon.
- Batman: The Animated Series:
- The Joker has used one at least twice.
- In "The Clock King", the eponymous villain use a pocket watch as this against Batman.
- Blazing Team is an entire series built on this.
- The Boy typically used special Yo-yos.
- In Gadget Boy & Heather, Gadget Boy uses a yo-yo to tie up the villains in the show's opening.
- In one episode of Hey Arnold!, Arnold's yo-yo proves fatal to Eugene's goldfish when it breaks from its string, falls into the goldfish bowl, and knocks over the toy knight, killing the fish.
- In an episode of Jackie Chan Adventures, a mobster uses a yo-yo to hit the button that will lower Jackie and Tohru into a shark tank. Moments later, Jackie uses the same yo-yo to entangle the mobster's feet, preventing his escape.
- Toyman utterly owns Killer Frost with one of these in the penultimate episode of Justice League Unlimited.
"Around the World. (Wham!) Rock the Cradle. (Wham!) Awww... sleeper."
- The main weapon of Ladybug in Miraculous Ladybug. She mainly uses it for Spidey-style Building Swinging. The string is as long as she wills it to be, she can Spin to Deflect Stuff with it, the whole thing is indestructible by mundane means, and she use it as a video phone. It's explicitly the product of the magical artifact that provides her powers.
- Velma's yo-yo in A Pup Named Scooby-Doo. Although it's not a killer, it's extremely helpful, as she used it to hold on trees, tangle villains, gain speed in their Mystery Skate...
- Wadi wields one in The Secret Saturdays.
- The primary weapon of Señor Yo-Yo in SheZow.
- The Smurflings used yo-yos against Gargamel in The Smurfs (1981) episode "Have You Smurfed Your Pet Today?"
- In Steven Universe, Smoky Quartz, Steven and Amethyst's fusion, combines their weapons into a large yo-yo, and uses it to trounce Jasper.
- SWAT Kats: Madkat uses a giant saw bladed yo-yo in the episode "Enter the Madkat."
- The yo-yo is pretty well-documented as one of the oldest toys in the world, but there's just about no historical evidence that it was ever used as a serious weapon. However, there was a recorded journal entry from Jose Rizal which stated that he demonstrated using the yo-yo as a weapon to European and American passengers in a ship he was travelling in.
- While not identical in style to a yo-yo, the boleadoras used in the Argentinian pampas, and a type of weapon known as the Slungshot, are certainly reminiscent of Killer Yo-yos.
- The Chinese yo-yo (aka the diabolo) , while not an actual weapon, can be spun to dangerous speeds that can result in the loss of teeth or eye(s) if the wielder loses control of it.
- A standard Western yo-yo, as noted above, can become the bane of babysitters and parents everywhere. Those fancy trick yo-yos that became fashionable around the turn of the millennium are even worse, as they have a longer cord, allowing them to be swung around with greater effect. Yo-yos made of aluminum, especially the ones with weighted inserts, are even more dangerous. Anyone just starting to learn tricks would be wise to use a mouthguard and mind their hands/wrists when throwing/returning the yoyo with any significant amount of force.