History Main / RedOniBlueOni

* Coca-cola and Pepsi. Coca-cola has survived by its aggressive and continual marketing campaign and bright, memorable advertisements, is incredibly popular, and is sold in red cans. Pepsi has a much more subtle presence in marketing, is considered by many to actually be the better of the two colas, and is sold in blue cans.
** YourMileageMayVary
*** UnderStatement
*** Pepsi is totally the Red Oni, in spite of the can color. Every single aspect of their marketing campaign is all about aggressively taking potshots at Coca-Cola. Coca-Cola's marketing generally involves adorable polar bears quietly enjoying a refreshing Coke.
* Theodore Roosevelt and Woodrow Wilson, the two famous Progressive-era Presidents. They aren't color-coded, but they fit the personalities well.
** Given the modern colors associated with their parties, they are.

The red oni is associated with passion, wildness, defiance and fire. A red oni character is often more brawny than brainy, enthusiastic, determined, and filled with a zest for life. He is also much more likely to break conventions and rules than his counterpart. Often an IdiotHero or, in more mature pieces, a BoisterousBruiser, (or at least having some qualities of one) and likely to be HotBlooded. If a red oni is indeed noticeably intelligent, he will still be much more emotional than the blue oni, and/or with less sophisticated thoughts, feelings, or goals. When a villain, a red oni is often a BloodKnight. Whereas his blue counterpart puts a lot of focus onto higher goals, causes, or [[HonorBeforeReason codes of behavior]], the red is usually more [[TheMcCoy concerned with people]]. Say something nasty about their country or cause, and they'll usually shrug or laugh it off. On the other hand, say or do something nasty to their [[{{Nakama}} closest friends]], and you've just guaranteed yourself [[RoaringRampageOfRevenge a world of pain]].

The blue oni is an opposite in most ways -- more intellectual, proud, traditional, cultured (sometimes more spiritual, although that's not guaranteed), and associated with water. Blue oni personalities are often respected by others, but also likely to puzzle or confound their peers because they are difficult to read and have a mysterious quality to them. Personality subtypes include TheStoic, TheSpock, TheQuietOne and the ever popular AloofBigBrother. (Pride, aloofness, or social ineptness also means they frequently [[CanNotSpitItOut have trouble spitting it out]], whatever "it" may be.) It's worth noting that while blue types ''appear'' tremendously calm and composed, sometimes this is just the surface, and scratching that facade may show that they are, if anything, wound '''far''' too tight beneath their calm and unemotional appearance. (This is particularly true of the villains). Villainous blue oni tend to be extremely ruthless, ready to do or sacrifice anything (and often anyone) to accomplish their goals. See KnightTemplar and WellIntentionedExtremist.

* {{Otomedius}} features the [[CreepyTwins Gofer Sisters]], R.B. (Red) and L.B. (Blue). To further drive home this trope, they favor those colors on their dresses and matched fighters, Hugin and Munin.

** Additionally, the [[FourIsDeath four]] Beastman generals have this dynamic as well, in a way. Thymilph and Adiane, the fire and water generals, are off-the-wall {{Berserker}} [[BloodKnight Blood Knights]] whereas Guame and Cytomander, the earth and air generals, are much smarter, calmer, and more calculating.

* How are [[{{House}} House and Wilson]] not on here already?
** Maybe because they're both different Blue Onis?

*** Also note the foreshadowing, as They are both [[spoiler:Zuko's ancestors, and Sozin left Roku to die under tons of volcanic soot.]]

* Subverted by the ''LastBlade'' series, where the reckless, [[ArrogantKungFuGuy arrogant]] Kaede is wears blue, and the TroubledButCute [[TheQuietOne Quiet One]] Moriya wears red and has red hair.

* Red and blue are on opposite sides of an RGB color wheel (red is only a primary colour on the traditional wheel; in the RGB wheel, it is a secondary color formed by the combination of green and yellow).

* Dagget (red oni) from ''AngryBeavers'' is highly emotional and prone to Donald Duck-esque rages; stark contrast to his older brother Norbert (blue oni), who is cool-headed, and considers himself suave.

[[folder: Other]]

* The Sentinel and Overseer of GaiaOnline.
** Interesting case: they fit the roles to a T during the Halloween event, but then get partially inverted during the Xmas event.

[[folder:Live-Action TV]]
* The main stars of ''{{Mythbusters}}'' Adam Savage and Jamie Hyneman. Both do the same job, but Adam does it flying by the seat of his pants, laughing and exclaiming over every explosion or test result, while Jamie coolly looks on. When one myth required them to use a remote control airplane to test the myth, co-star Grant talked about the differences in personality.
-->'''Grant:''' Adam is a very exuberant personality, so I expect him to crash the plane very quickly. Jamie is a much more controlled personality, so I suspect he's going to be able to fly it better and that he'll be our pilot in this test.
[[/folder]]

[[folder:Theater]]
* [[WaitingForGodot Vladimir And Estragon]].
* And along the same lines as the above example, [[RosencrantzAndGuildensternAreDead Rosencrantz (red) and Guildenstern (blue)]]
* ''{{Hamlet}}'' (red) and Horatio (blue). [[ZerothLawOfTropeExamples Which makes this...]]
* In the movie version of the [[http://tvtropes.org/pmwiki/pmwiki.php/Theatre/Ptitle3e9epo6m musical Jekyll and Hyde]] (yes, the one with [[GermansLoveDavidHasselhoff David Hasselhoff]]), Dr. Jekyll is shown with a [[http://s233.photobucket.com/albums/ee306/Loracarol/?action=view¤t=Jekyll.jpg red light]] (hard to tell in this picture, sorry), and Hyde is shown with a blue light shining on [[http://s233.photobucket.com/albums/ee306/Loracarol/?action=view¤t=Hyde.jpg him]]
* ''RomeoAndJuliet'' gives us Romeo (red) and Benvolio (blue), Mercutio (red) and Benvolio (blue), and even Romeo (red) and Juliet (blue).
* To a degree, Henry Higgins (red) and Colonel Pickering (blue) from ''{{Pygmalion}}'' and ''MyFairLady.''
[[/folder]]

* A Meta example (which is occasionally lampshaded in other works) is in video games where [[ColorCodedMultiplayer Players 1 and 2]] are usually assigned these colors.
* The main stars of ''{{Mythbusters}}'' Adam Savage and Jamie Hyneman. Both do the same job, but Adam does it flying by the seat of his pants, laughing and exclaiming over every explosion or test result, while Jamie coolly looks on. When one myth required them to use a remote control airplane to test the myth, co-star Grant talked about the differences in personality.
-->'''Grant:''' Adam is a very exuberant personality, so I expect him to crash the plane very quickly. Jamie is a much more controlled personality, so I suspect he's going to be able to fly it better and that he'll be our pilot in this test.

* Interestingly, while you'd expect [[TransformersAnimated Jetfire and Jetstorm]] to follow the trope (they even have red and blue color schemes, respectively), they avert the trope by both acting pretty red. Of course, they are working for [[{{jerkass}} Sentinel Prime]], so who knows how that affects their personalities.

[[SkyGirls http://static.tvtropes.org/pmwiki/pub/images/red_girl_blue_girl_2450.jpg]]
[[caption-width:325:One of these twins is probably enjoying introductions more than the other.]]

-->'''Zodd''': ''I'm going to take a wild guess and assume that you two have a [[{{Naruto}} Naruto/Sasuke]] best friend/eternal rival thing going on.''
-->'''Guts''': ''Uh...that's great. Are you going somewhere with this?''
-->'''Zodd''': ''Do you remember a little thing called "Valley of the End"?''
-->'''Guts''': ''So you're saying that Griffith and I are going to have a falling out, and Griffith is going to turn into a winged, lipstick monster. [[{{Lampshading}} That seems a little farfetched]].''
-->- ''{{Berserk}} [[AbridgedSeries Abridged]]''

-->''These two really are birds of a feather, but also total {{foil}}s to each other. The idea of them being exactly the same and yet polar opposites is going to be a huge factor in upcoming episodes.''
-->--JesuOtaku discussing Vash and Wolfwood from ''{{Trigun}}''.

* RyuandKen from ''StreetFighter''. Ryu is philosophical, traditional, and prefers using the fireball from a distance, while Ken is brash, cocky, innovative and his favorite move is the uppercut, best performed at close range.

** And reversed in the United Kingdom and Canada, where the main left-leaning parties (Labour and Liberals, respectively) are identified by the colours red and yellow, while their opponents in the Conservative Parties are identified by blue. In this case, the use of red is derived from the socialist and social democratic associations of each party, while blue was traditionally associated with the monarchy and other such traditional institutions.

** And reversed in the United Kingdom and Canada, where the main left-leaning parties (Labour and Liberals, respectively) are identified by the colour red, while their opponents in the Conservative Parties. In this case, the use of red is derived from the socialist and social democratic associations of each party, while blue was traditionally associated with the monarchy and other such traditional institutions.

* ''{{Bionicle}}'': [[PlayingWithFire Tahu]] and [[AnIcePerson Kopaka]]
** Later on it gets kind of turned around with the calm and professional [[PlayingWithFire Toa of fire]] [[TheCaptain Jaller]] and the compassionate, warm, and [[DeTerminator determined]] [[AnIcePerson Toa of Ice]] [[TheChosenOne Matoro]].

* A Meta example (which is occasionally lampshaded in other works) is in video games where Players 1 and 2 are usually assigned these colors.

* Although, at first, Stan and Kyle from ''SouthPark'' had similar personalities, later on, they were differenced. Stan was an introvert, calm DeadpanSnarker, while Kyle was an impulsive, bold HotBlooded, especially in Cartman's presence.