[[quoteright:236:[[ComicBook/WonderTwins http://static.tvtropes.org/pmwiki/pub/images/Wonder_Twin_Powers_Activate_5653.jpg]]]]
[[caption-width-right:236:Form of ... [[WhatKindOfLamePowerIsHeartAnyway a bucket of water!]]]]

''Wonder Twin powers: activate!''

A good [[ConservationOfCompetence leash]] to amazing powers is the need for two characters to work together to activate them. Sometimes this is a supervillain and superhero, other times it's a superhero duo. Most of the time, the characters even get to be twins. Interestingly, their actual powers sometimes have nothing to do with their inherent twinness, unless their powers tap into [[CreepyTwins specific eerieness]].

Presumably, their in-built weakness is being ineffective unless they're together. [[MostCommonSuperpower Not truly related to a certain kind of "Wonder Twins."]] See also {{Synchronization}}, SiblingTeam and BashBrothers. Contrast with AllYourPowersCombined.
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!!Examples:

[[foldercontrol]]

[[folder: Anime and Manga ]]
* ''Manga/MiracleGirls'' fits the name so well that it might have been the trope namer. Mikage and Tomomi are identical twins (albeit with different hairstyles), who need to be in physical contact to teleport.
* The original versions of ''Anime/PrettyCure'' have individual powers of agility and strength, although nearly all of their magical attacks depended on contact with each other. It wasn't until ''Anime/YesPrecure5'' that the {{Magical Girl}}s could even transform by themselves.
** Much to the dismay of the {{Trope Namer}}s... Nagisa and Honoka are the current [[Pantheon/{{Magic}} Goddesses of this Trope]].
* ''Anime/SailorMoon'' originally played with this trope by suggesting while Chibi-Usa's powers are mostly useless, using them with Usagi's similar ones results in something powerful. In the fourth season, this was taken further when they couldn't even transform or deliver a finishing attack without being together. Many fans cite this as a detriment to Usagi's role as the show's star, but also a plot device to handwave Chibi-Usa's increased screentime pushing out the main cast. Unlike ''Anime/FutariWaPrettyCure'' and ''Anime/FutariWaPrettyCureSplashStar'', the noticeable age difference in the two made for some acrobatics to make sure the two [[MustHaveLotsOfFreeTime just happened to be together at the time]].
** Also in ''Sailor Moon'', Cyprine and Ptilol's strongest power requires the two to work together: one of them absorbs any incoming magical attacks, the other reflects them. Naturally, the Senshi defeat them by tricking them into separating.
* Ho and Ban, the twin Bount from the filler arc in the ''Manga/{{Bleach}}'' anime. Although they can control their more-or-less identical "dolls" separately, their real power comes from the dolls working in tandem. When one twin is knocked out, the other has to control both dolls at once and ends up overwhelmed.
* ''Franchise/{{Digimon}}'' and their human partners. Which always gave rise to the question, how did ''wild'' Digimon [[PowerLevels evolve]] without ThePowerOfFriendship?
** It seems that it happens easily enough with time - there are isolated incidents of non-partnered Digimon being able to do it on their own, and it also seems to be hinted at with the level names in the original Japanese ('Child', 'Adult', etc). Essentially all the Power of Friendship does is let the kid partners skip a few levels for a couple of minutes.
*** The biggest proof of this is Gatomon: since she didn't get to meet her partner early enough, she had to survive all by herself. As a result she evolved naturally, and her Adult form is her standard form, meaning she doesn't need her partner's power to keep it that way. However, going beyond it does require her partner's help. Later seasons would have partners of all stages.
** In ''[[Anime/DigimonTamers Tamers]]'' and ''[[Anime/DigimonFrontier Frontier]]'', it seems they do this by killing each other and absorbing the loser's data. Even those seasons, though, have civilian Digimon of high levels, such as a Mega-level ''shopkeeper'' and ''old Jewish couple.'' (Well, the Jewish-ness may be limited to the English dub...)
*** A more traditional example is Nefertimon and Pegasusmon, who have an attack that requires both of them.
** ''[[Anime/DigimonXrosWars Xros Wars]]'' vacillates between this and FusionDance: some [=DigiXros=] combinations transform one character into a new form for the other to wield, such as Dorulumon turning into a cannon for Shoutmon to aim and fire.
* The [[DropTheHammer Goldion Crusher]] in ''Anime/GaoGaiGar FINAL'' requires the authorization of the GGG (from the key held by Chief Taiga) and the UN (the key held by Swan White). Plugging them both into a pair of circular consoles causes the consoles to form the kanji for "victory". There's also [[FusionDance Symmetrical Docking]]; an issue in the early series was deploying [=HyoRyu=] and [=EnRyu=], as the combiner [=ChoRyuJin=] was the only one who could operate the Eraser Head missile.
* Viola and Cesario from ''Anime/KiddyGrade''. Cesario's ability, "Driver", does nothing by itself, while Viola's power, "Calamity", can manipulate matter at the atomic level, but requires "Driver" as its energy source. (Tweedledee and Tweedledum also have an ability (Windstorm) that they can coordinate with each other, and in the last episode of season 1, [[spoiler:Eclair acts as a power source for Lumiere's Puppet ability]].
* Time travelers in ''Manga/NatsuNoArashi'' depend on being close to each other to jump through time. As Arashi points out on her second trip, without someone else, she has no way to return to the present.
* Also reversed in ''Manga/{{Cyborg 009}}''. PsychoElectro 0010 turns out to be a pair of twins (+ and -) who ''die'' when forced to come into contact.
* The protagonists Black and White and the Dusk and Dawn brothers in ''Anime/TekkonKinkreet''. Although its more of a spiritual connection than anything else.
* Kikumaru Eiji and Oishi Shuichirou in ''Manga/ThePrinceOfTennis'' are Seishun Gakuen's "Golden Pair" and later on in the series are able to perform [[spoiler:Synchronization, letting them move as one and basically becoming an unstoppable badass doubles team.]]
* Masao and Kazuo Tachibana in ''Manga/CaptainTsubasa'' with their Skylab combinations and Triangle Shoot. In the series, they are almost useless if they're not playing together.
* In ''Manga/TheLuciferAndBiscuitHammer'', Yuki and Subaru have to hold hands to use their Strongest Spear and Strongest Shield powers.
* The twins from ''Anime/HeroicAge'' were two of the strongest human telekinetics but they could only use their powers when together, though not necessarily in contact. [[spoiler:Whether the limitation still existed after the departure of the Silver Tribe or due to force of habit they still joined hands to use their powers even after receiving a massive power boost.]]
* Campachino and Brindo from a ''Manga/OnePiece'' filler arc. They use an ability called Combination Play, in which they [[SelectiveMagnetism magnetically attract and repel each other]] and say that they can do it because of their "[[PowerOfLove brotherly love]]".
* ''Anime/HimeChenOtogiChikkuIdolLilpri'' the 3 girls must be together to transform into Lilpri, this forces them to get along.
* Rika and Satoko's finishing move in the MagicalGirl OVA episode of ''VisualNovel/HigurashiWhenTheyCry''.
* ''Anime/FushigiboshiNoFutagohime'' has twin princesses Fine and Rein, who can only transform and unleash their most powerful finishing attack when they're together.
[[/folder]]

[[folder: Comic Books ]]
* Aurora and Northstar of ''ComicBook/AlphaFlight'' have {{Flight}} and SuperSpeed individually, but can emit bursts of light and heat when touching.
** This was later inverted when Aurora had her powers modified so she could use her light powers without touching her brother. Afterward, touching caused them both to lose their powers for a while.
* After being stripped of his GreenLantern status, all-around troublemaker Guy Gardner got his hands on the yellow power ring once worn by the Lanterns' arch-nemesis, {{Sinestro}}, and found that it came with a significant drawback: It drew power from other power rings, so to keep it fully charged, he had to periodically seek out and fight other Green Lanterns. Given that Guy is and was the biggest {{Jerkass}} in TheDCU and lovin' every minute of it, this wasn't a huge problem. (At present, Sinestro's ring and others like it no longer suffer this drawback, instead drawing power from their own power source like the Lanterns'.)
* In MarvelComics, Andreas and Andrea von Strucker, the Fenris twins, have to be touching to fire energy bolts. Following Andrea's death, [[spoiler: Andreas became the new Swordsman, activating his powers by wielding a sword with her skin covering the hilt]].
** When [[spoiler: Andrea was resurrected (it didn't last), Andreas flayed the skin off his arm to give to her.]] Because they're [[CreepyTwins creepy]].
* Hawk and Dove in the DCUniverse.
* One of the main elements governing powers in ''Comicbook/QuantumAndWoody'' is their gauntlets, one for each of them. Due to the accident that gave them powers, they need to clang them together every 24 hours or they'll simply break up and vanish.
* Crimson Crusader and Imp of Marvel's ''Comicbook/ClanDestine'': Unlike the rest of their siblings, their powers emerged at puberty, not at adulthood. But that same odd "twin factor" that gave them their powers early, causes their powers (Crusader controls gravity, Imp can generate and control radiant energy) to fail if they're physically too far away from each other.
* One of the earliest examples (from the 1940s) of this was DCComics' superhero duo ''TNT and Dan the Dyna-Mite'', who had to touch their rings together (they had "positive" and "negative" charges) in order to activate their powers (superstrength and energy projection.) In ''The Young All-Stars'', the sequel series of the ''ComicBook/AllStarSquadron'', T.N.T. was killed, and Dyna-Mite thought he wouldn't be able to activate his powers without his partner, but he eventually found out that he could reactivate them by wearing both dyna-rings and pressing them together himself.
* The comic book series ''{{Capes}}'' features a duo of {{Punch Clock Hero}}es, Ed and Marshall, who can't be more than thirty feet away one one another or they'll weaken. [[PunnyName Claire Voyant]] [[TwinThreesomeFantasy immediately sees]] the PowerPerversionPotential. In the end, Marshall dies but the power still holds, forcing Ed to carry around Marshall's urn all the time.
** In the end, to defeat a BigBad, Ed ''swallows'' Marshall's ashes and is transformed into a new superhero who saves the day. (And then promptly leaves the planet.)
* At least one version of the alien 'Blood Brothers' required them to be near each other in order to keep up their massive strength. IronMan once beat them by getting Comicbook/{{Daredevil}} to lure one away, so their individual strength dropped.
* {{Superman}} faced a husband and wife team called Sodom and Gomorrah. While touching, they could fire blasts that turned anything they hit into salt. Superman separates them and captures Sodom, but his wife escapes.
* Played with in ''{{Irredeemable}}'': twins Scylla and Charybdis initially only had powers when they were in close proximity to each other but it was later revealed to be untrue. Charybdis was the one with powers and Scylla was only ever borrowing from him.
* The Jade Dragons of ''ComicBook/AstroCity'' are a brother/sister martial arts team who can summon a giant dragon by lining their arms together.
* ''BallAndChain'' is about a married couple whose powers only work when they're together and are triggered by their physical contact. The problem: they were splitting up when they got said powers and have a lot of trouble cooperating. Secondary problem: Neither of them was aware of this caveat for a while, meaning that when Edgar ("Ball") got ambushed by bad guys he thought he was going at them with superpowers that were waning rapidly.
* The {{New52}} version of ''The Ravagers'' supporting characters Thunder and Lightning, in addition to their respective sonic blast and electric powers, can fly as long as they're touching each other. Interestingly, only one of them has to ''want'' to fly for it to work.
[[/folder]]

[[folder:Film]]
* The ''Film/DoubleDragon'' movie had this as the only way the two halves of the [[MacGuffin Dragon Medallion]] could be used without corrupting the user with its power, with Billy using one half and Jimmy using the second.
* Reversed in ''{{Hancock}}'', where once a pair of superheroes (a man and a woman) that were made for each other are united, they start losing their powers, so they can live [[IJustWantToBeNormal normal lives.]]
[[/folder]]

[[folder:Literature]]
* In ''Literature/{{Dragonlance}}'', the only way to enter the Portal to the Abyss where Takhisis lives is to have both an evil mage and a good cleric activate it. Raistlin [[spoiler:takes advantage of a cleric, Crysania and uses her for protection throughout the Abyss. Then, while she is dying, he abandons her, kills the pantheon of Krynn, and ascends to godhood. Caramon ends up going back in time to warn him about the after-effects, though.]]
* In ''Mindstar Rising'' (the sci-fi mystery novel by PeterFHamilton) the psi-boosted protagonist and his pre-cognitive partner are successfully ambushed when twin psychics are used to create a null-zone where their powers won't work.
* In ''Son of Literature/{{Spellsinger}}'', Jon-Tom's son and Mudge's kids have to perform together as a band to gain the full benefits of spellsinging magic. They're a trio, not a duo, but same idea.
* In ''Literature/{{Xanth}}'', after awhile, it's discovered that some groups thought to lack magic talents, such as [[{{Muggles}} Mundanes]], goblins and harpies, can sometimes have shared talents that can only be invoked when they're in contact with the person who shares their talent. However, none of these guys are twins. Some examples are [[HybridMonster Gloha Goblin-Harpy]]'s parents and a pair of Mundanes who have two different syndromes making one unusually short and the other unusually tall.
* In the young adult fantasy series ''Literature/TWitches'', main characters Camryn and Alex are powerful twin witches separated at birth whose powers become super-strong when they work together.
* The [[http://en.wikipedia.org/wiki/Morgan_Llywelyn Morgan Llywelyn]] / Michael Scott novel ''Silverhand'' features a brother/sister villain team dubbed "The Duet", who are able to summon a WorldWreckingWave. For added {{squick}} value, in order to do this they [[{{Twincest}} have sex]].
[[/folder]]

[[folder: Live Action TV ]]
* Maya and Alejandro Herrera from ''Series/{{Heroes}}'' are playing with this trope - Maya's [[PowerIncontinence uncontrollable]] deadly poison emission is countered and neutralized by Alejandro's power, making them sort of like the Wonder Twins stuck on "Form of Mass Murder!" "Shape of {{Retcon}}!"
* Shotaro Hidari and Phillip from ''Series/KamenRiderDouble'' have to transform at the same time to form the titular Rider. The psychic connection powers of their TransformationTrinket let them easily do this even from across town, but if Phillip is unconscious, being chased, or just has something better to do, then Shotaro is screwed.
** In addition, if it's ''Phillip'' who's in trouble, he can't transform unless he contacts Shotaro and has him put on the Double Driver.
** Other complications include loss of synchronization paralyzing Double, and the fact that the Double Driver can (and has) been disabled by blocking off one of the ports.
*** Shotaro eventually gains the ability to transform solo into Kamen Rider Joker, but as a matter of preference only uses it when it's absolutely impossible to become Double, such as when the original TransformationTrinket has been disabled or [[spoiler: Phillip is dead]].
* ''{{Smallville}}'' had some CreepyTwins (though adults) who could generate [[BarrierWarrior force fields]] when their hands touched.
** The ''actual'' Wonder Twins have since turned up. Complete with "Powers, activate!"
* In early ''Series/StarTrekTheNextGeneration'' episodes, the phaser pistols could only work when activated by touching a pair of them together. Once someone noticed that this meant any solitary character was basically doomed, the feature was quietly dropped.
[[/folder]]

[[folder: Multiple Media ]]
* The Skakdi race fom ''{{Bionicle}}'' have been granted ElementalPowers, but they can only be used in tandem. This is a safety measure -- since the Skakdi are AlwaysChaoticEvil but all hate each other. The prospect of having to work together is sometimes enough to keep them from tapping into the elements. Unfortunately, they also won the SuperPowerLottery, so being unwilling to use elemental powers is hardly a hindrance to them.
[[/folder]]

[[folder:Podcasts]]
* Torchlight, Billy's character in [[Podcast/{{Fandible}} Fandible's]] [[http://paradigmconcepts.com/rotted-capes/ Rotted Capes]] game. Used to be part of a pair of [[WonderTwinPowers power twins]], until his sister got bitten by zombies. Now, she wants to bite him, so they can ''both'' be super zombies, and restore their [[WonderTwinPowers twin powers]]. His fire powers are [[BoozeBasedBuff fueled by alcohol]]. [[TheAlcoholic He's got it under control, honestly!]]
[[/folder]]

[[folder: Tabletop Games ]]
* Rant and Rave of the ''MutantsAndMasterminds'' Freedom City supplement, are a brother/sister pair with sonic and visual distortion powers respectively, but can deploy a disintegration attack when physically touching.
* One ''DragonMagazine'' article introduced the Dvati, a race in which each individual member is actually a pair of twins who share a soul, to ''DungeonsAndDragons''. They have to act in unison to cast any spell.
* In TabletopGame/{{Pathfinder}} Art of Magic splat book, there is a spell temporarily binding the minds of the caster and another character. This allows them to both use the best natural roll they make for initiative, and also increase their spellcasting effectiveness if they cast spells at the same target.
[[/folder]]

[[folder: Video Games ]]
* ''Franchise/FinalFantasy'':
** In ''VideoGame/FinalFantasyIV'', Palom and Porom have the ability to cast spells together in order to produce miniature versions of two of the most powerful abilities in the game: Megaflare, Bahamut's ability, and Meteor, the ultimate Black Magic. However, these abilities were toned down in power significantly. Ironically, their high MP cost to both twins and long casting time made them very inefficient, such that given the twins' fast learning rate, they both become '''more''' powerful individually than together if you take time to level them up.
*** As an Augment, Twincast allows the final party to raise all their HP caps, buff physical and magic attack power, and cast a devastating White Magic spell. The same flaws still apply, so your mileage may vary, but it's Rosa's only other magic offense besides Holy.
** ''VideoGame/FinalFantasyIX'' has Zorn and Thorn, twin jesters that give each other meteor and flare powers during one mini-boss sequence. The trick is to hit the jester who just received the power before he can use it. [[spoiler: Though it turns out they're actually one creature with two bodies.]]
* In ''{{Spyro}} 2: Ripto's Rage/Gateway to Glimmer'', in Scorch, the exiting cutscene shows siblings (twins? They don't say) Handel and Greta surrounded by armed soldiers in a castle. As the bad guys approach, Handel and Greta slowly move their hands together and when they join hands, their eyes turn red and they cast some sort of spell that knocks their enemies off the castle.
* ''[[Franchise/{{Pokemon}} Pokémon]]'' has two abilities called "Plus" (exclusive to Plusle) and "Minus" (exclusive to Minun). Each raises the Special Attack stat of a partner with the other by 50% - but ONLY when both are present in a double battle. Their stats make them [[JokeCharacter almost absolutely worthless]] in any other scenario.
** As of Black and White, these abilities are no longer exclusive, Plus/Plus and Minus/Minus pairs still boost and can potentially be used to greater effect with the new Triple and Rotational battles. This is still a problem though, as none of the 3 new users are very good, and are fairly redundant with each other.
* In ''[[BackyardSports Backyard Baseball]]'', Ashley and Sidney Webber play much better when they are on the same team. They become the best pitchers in the game.
* ''{{Suikoden}}'' plays this with characters with look-alikes. Each pair can perform combinations when they're in the same team. ''SuikodenV'' has [[TheHero the Prince]] and Roy. ''[[SuikodenTierkreis Tierkreis]]'' has Marica and Another Marica.
* DualBoss Mona and Lisa in ''VideoGame/StreetsOfRage 3'' have several abilities that they can perform if they do it together. When you kill one of the twins, the remaining twin's abilities will weaken due to being alone.
[[/folder]]

[[folder:Webcomics]]
* In the ''[[Webcomic/TheOrderOfTheStick Order of the Stick]]'' book "StartOfDarkness", it is revealed that [[spoiler:the power of the Snarl gates can only be harnessed by a cleric and wizard working together. Though some people, such as Tsukiko, are both.]]
* ''KillroyAndTina'' has the two main characters share super powers as long as they're within five kilometers of each other. They also suffer from {{Synchronization}}; if one dies, both die. This was actually done as ''punishment'', as a type of RestrainingBolt to keep an evil alien overlord tethered to an ordinary teenage girl, and therefore out of trouble. [[spoiler: Although it was also part of a scheme involving a StableTimeLoop, because the superhero who arranged this was actually a future version of Tina.]]
* Dimitri and Alina Tokamak of ''Webcomic/DresdenCodak'' have superpowers activated by contact based around physics.
* Parley and Smith Of ''Webcomic/GunnerkriggCourt'': both have powers that work individually (Teleportation and [[http://www.gunnerkrigg.com/archive_page.php?comicID=385 creating order]]) but when the two are working together, Parley's teleportation is much [[http://www.gunnerkrigg.com/archive_page.php?comicID=786 easier to control]].
[[/folder]]

[[folder: Web Original ]]
* In the WhateleyUniverse, the supervillains The Twin Terrors get stronger as they get closer together, with energy powers when they are next to each other. At a distance, they seem to be ordinary Exemplars. Next to each other, they outpowered Lancer.
** Phobos and Deimos, the Fury Twins, have a fear aura. The closer together they get, the worse it grows. When they get too close, they can accidentally merge into a two-headed monstrosity with a fear aura so powerful [[RealityWarper it warps reality around them]]. They hate it.
[[/folder]]

[[folder:Western Animation]]
* The {{Trope Namer}}s are the ShapeShifting ComicBook/WonderTwins Zan and Jayna from ''[[WesternAnimation/{{Superfriends}} The All-New Superfriends Hour]]''. When they [[HandshakeSubstitute bumped fists]] to activate their powers, Zan could change into various forms of water/ice, while Jayna could transform into animals. Sadly the writers were either unable or forbidden to come up with [[WhatKindOfLamePowerIsHeartAnyway actual, useful applications for their powers]]. Their counterparts from the ''Superfriends'' comics of the time were much better with their powers.
* Más y Menos from ''WesternAnimation/TeenTitans'' were {{Fragile Speedster}}s whose powers depended on physical contact with each other (usually by pressing their palms together) or holding an electrical conductor between them. They themselves are arguably derived from the Tornado Twins of Creator/DCComics (who did not have this limitation).
* Mermaid Man and Barnacle Boy of ''WesternAnimation/SpongebobSquarepants'' are a parody of this, with them yelling "Mermaid Man and Barnacle Boy Unite!" before activating their powers.
* ''TransformersAnimated'': Jetfire and Jetstorm combine to make "Safeguard".
** In fact all CombiningMecha have a bit of this, in that they're devastating in a FiveManBand, but nothing to write home about individually.
** Oh, individually, they've got PlayingWithFire and BlowYouAway going for them, respectively. They're not overly reliant on Safeguard mode.
* In ''[[WesternAnimation/TeenageMutantNinjaTurtles2003 Teenage Mutant Ninja Turtles]]'' (2003), assassin duo Mr. Touch and Mr. Go need to bump fists in order to (temporarily) access their powers: super-strength for Mr. Touch, super-speed for Mr. Go. Given that these fade in a matter of minutes, they're [[ThoseTwoBadGuys always together]].
* The [=WooFoo=] Aura attack from ''WesternAnimation/YinYangYo'' requires the twins to quit fighting and work together in mutual concentration.
* Parodied on one episode of ''CampLazlo''. When Chip and Skip, the dung beetles, join hands and shout "Scum twin powers, activate!" they can call all the grime in camp to the area.
* ''WesternAnimation/TheTwinsOfDestiny'' was a French production in which the main characters, Jules and Julie, would hold hands and say "We call upon the (number) Power of the Seven Powers..." and then fill that last part in with whatever they needed the power to do.
* In ''CaptainPlanetAndThePlaneteers'', the Planeteers all had rings with individual powers but [[AllYourPowersCombined only when all five of them used them together could they summon Captain Planet.]]
** Actually the only Planeteer who is ''absolutely'' necessary to form Captain Planet is Ma-Ti. There was an episode (the name escapes me but it does exist) where Linka and Wheeler were abducted by aliens that collected endangered species to house in a sanctuary on their home planet. The remaining Planeteers were still able to create Captain Planet (admittedly he couldn't fly but they did manage to create him).
*** More exactly, the Heart Planeteer is the one who's vital to summon Cap. In another episode Ma-Ti was knocked unconscious ''in the middle of the summoning'', and Gaia solved the trouble via temporarily handing the Heart Ring to a Native-American boy that [[HeroicBystander had helped the Planeteers before.]]
* Despite being sentient themselves, the HumongousMecha in ''{{WesternAnimation/Robotix}}'' could only activate their [[TransformingMecha transforming powers]] when they had human pilots.
* In ''WesternAnimation/DrakPack'' by HannaBarbera, the three main characters can only shift from their human to their monstrous [[CursedWithAwesome (and super-powered)]] forms by touching each other... [[ByThePowerOfGrayskull and shouting]] "[[TotallyRadical Whacko!]]"
* On ''CodenameKidsNextDoor'', the Kids Next Door Code Module is protected by a dual key system that requires two operatives to give their authorization codes to access it.
* Magnokor of ''WesternAnimation/{{Inhumanoids}}'' is a borderline case, as he/they get referred to as a singular creature, but actually demonstrate two separate identities that argue with one another, even when merged as a two-headed monster. Only when split into two bodies can he/they trap Metlar in a magnetic field, and hence qualify for this trope.
* In ''{{Shazzan}}'', Chuck and Nancy each wore half of the ring. To summon Shazzan, they put the ring together and said "Shazzan!"
[[/folder]]

[[folder: Real Life ]]
* Related to this is the real-life "dual key" system for nuclear weapons- American nuclear weapons require two people (at least) to launch them.
** This is basically a more extreme version of the ubiquitous safety trigger, in which two buttons must be depressed simultaneously in order to activate something dangerous, such as a taser or circular saw.
* Valuable assets are sometimes protected by requiring more than one person to open a safe, sign a check, etc, so that any illicit access will require a conspiracy rather than just one person.
[[/folder]]

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