Evil Duo

This is a common pairing of bad guys constructed along the same lines as a Freudian Trio, except for one important factor: They left off the reasonable character. In the classic The Dragon pairing, for example, the Evil Overlord is very Superego-ish, who is wanting a maximum amount of rule and control, and the Dragon, who basically just wants to fight, is very Id-ish. The lesson being that without the moderation of the Ego, things can get really out of hand.

Subtrope of Foil

See also: Power Trio, Comic Trio, Terrible Trio, Quirky Miniboss Squad. Overlaps with Brains and Brawn and Those Two Bad Guys. See also Big Bad Duumvirate. Usually also an example of Red Oni, Blue Oni.

Anime and Manga

 * Androids 17 and 18 from Dragonball Z are a more subtle version of this. 17 is portrayed as wild and fun-loving (at least as far as androids go), while 18 is pragmatic and critical of 17's sacrifices of efficiency in the name of fun.
 * Interestingly enough they weren't particularly evil in the main timeline. In the original timeline that Trunks came from they were both mass-murdering Complete Monsters, but in the main timeline they were mostly neutral. They did originally intend to kill Goku but didn't go out of their way to hurt anybody else. Eventually both make Heel Face Turns and 18 even has a daughter with one of the protagonists.
 * Most of the Akatsuki partners in Naruto are constructed along these lines, with one partner being cold and focussed, and the other a raving lunatic. Examples include Itachi (a Stoic badass who barely talks) and Kisame (Affably Evil Blood Knight), Hidan (Dumb Muscle Talkative Loon) and Kakuzu (Genius Bruiser and The Strategist), and Sasori (icy People Puppets collector) and Deidara (Axe Crazy Mad Bomber). Pain and Konan avoid this; Zetsu, interestingly, does not, suffering from a split personality that gives him one calm half and one crazy one.
 * In Shakugan no Shana, Crimson Denizens of Bal Masque usually work in pairs—a Wanderer (a fighter) and a Jaeger (a scout); such as Ribesal and Pirsoyn.

Comic Books

 * In DC Comics, when Lex Luthor and The Joker team up (as happens often enough), they practically define this pairing.

Fan Works

 * Though they're not the only members of the Quirky Miniboss Squad, Mireyes and Binbeat of Futari wa Pretty Cure Blue Moon appear to count. They tend to be put together on missions (save for in their introductory episodes), with Mireyes making sure Binbeat doesn't make any trouble they're not supposed to be making, and Binbeat whining and preferring to just play around and prank people.
 * A Dark Knight Over Sin City has a few since it involves team ups between some Batman and Sin City villains. They all have varying degrees of lunacy so they clash quite a bit. For instance, Manute is cool, quiet, and level-headed, while Riddler annoys him by being a melodramatic villain prone to Evil Gloating.

Film

 * Br'er Fox and Br'er Bear in Disney's Song of the South. Fox is more concerned with catching Br'er Rabbit his way, while Bear just wants to "knock his head clean off", making them easy prey for Br'er Rabbit.
 * Cohen and Tate in Cohen and Tate

Live-Action TV

 * Malcolm and Jamie from The Thick of It have unique ways of controlling their enemies. Malcolm uses his frightening degree of charm to manipulate them. Jamie threatens to push iPods up their penises.
 * Except when they're beneath Malcolm's dignity to manipulate, in which case he just shouts a lot. With rather colorful turns of phrase. Basically, Jamie is Malcolm without the people skills.

Music

 * The titular children from the song "Those Two Dreadful Children" by Cruella De Ville.

Video Games

 * Prometheus and Pandora from Mega Man ZX Advent.
 * In Knights of the Old Republic there is (in order) Darth Revan and Darth Malak, Darth Malak and Admiral Karath, Darth Malak and Bastila, and finally (in the Dark Side ending), Darth Revan and Darth Bastila.
 * The combination of Emperor Gestahl and Kefka in Final Fantasy VI show that things can really get out of hand when
 * from Fate Stay Night. wants to conquer the world so he can rule over it, while  just wants to inflict the maximum amount of suffering and death that he can upon humanity for his own amusement. These would seem mutually exclusive, but 'luckily'  has decided that the majority of humanity isn't worthy to be ruled over and has no problem with wiping out most of the 'mongrels'.
 * The prequel Fate/zero has the master Uryuu Ryuunosuke and his Servant Bluebeard. Both are Serial Killers and take great pleasure in admiring each other's handiwork. Bluebeard is marginally more goal-oriented in that he (technically) is in it for the Grail, while Uryuu is an outsider who got roped into the Grail War by accident and merely takes all the pleasure he can out of making everyone near him suffer alongside his supernatural Cthulhu-summoning new best friend.
 * In most games of the Castlevania series, Dracula and Death are partners; if Dracula isn't in the game, it usually means he's dead and Death is behind some plot to fix that.

Web Comics

 * The Beast Legion has had several Evil Duos:
 * Viper Twins in Issue 2.
 * Leviatha and Stampede in Issue 5, although they don't get along too well.
 * Leviatha's minions Jawbraxus & Octacreep in Issue 5.
 * Clawborr and Chou in Issue 6.
 * The Order of the Stick: Xykon and Redcloak, inverted in that Big Bad Xykon is the id, while Redcloak, The Dragon, represents the superego.
 * Also serves as a Deconstruction of the typical set-up: in the prequel Start of Darkness, Redcloak is the leader. Xykon usurps him spectacularly.
 * Dom and Ed from Megatokyo.
 * Maerril and Rowasu of Juathuur.

Western Animation

 * Invader Zim and GIR. Zim is an oblivious megalomaniac whose plans are usually doomed from the get-go. GIR is a childish Cloudcuckoolander with no attention span.
 * But that's OK because GIR has waffles and pretty girls to take him to raves. Zim really has no friends other than GIR.
 * Another example of an Evil Duo would be Almighty Tallest Red and Purple, though technically they are both Evil Overlords. Still, Red is usually the Straight Man to Purple, who is often the dumber and lazier of the two.
 * Dick Dastardly and Muttley from Wacky Races and Dastardly and Muttley in Their Flying Machines.
 * Pinky and The Brain are a borderline example because A) Pinky is not evil, just too stupid to recognize it, and B) the Brain is more competent that most of the other examples. Then again, he is a lab mouse trying to take over the world, so maybe he does fit.
 * Lugnut and Blitzwing in Transformers Animated. While Lugnut is singleminded and slavishly devoted to Megatron, Blitzwing is of three minds about everything (literally) and doesn't seem to really care much about Megatron.
 * Maximus and Minimus in Atomic Betty.
 * The Monarch and Dr. Girlfriend by season 3 of The Venture Brothers.
 * A bit different in that, while the Monarch certainly fits the 'id' profile, Dr. Mrs. The Monarch is actually competent and reasonable in her own right, rarely given over to histrionics, in other words, a very well-composed 'ego'.
 * Dr. Drakken and Shego from Kim Possible. They fit this trope exactly, as he's a Mad Scientist who wants to Take Over the World, while she's content to do the stealing and fighting with teen heroines.
 * Bebop and Rocksteady in Teenage Mutant Ninja Turtles.
 * Flint Marko/The Sandman and Alex O'Hirn/Rhino in The Spectacular Spider-Man. Marko is the Superego, concerned only with getting his "Big Score" and completely defying things such as revenge and grudges, while O'Hirn is the Id who mindlessly rushes into fights and problems without thinking things through.
 * In Spider-Man: The Animated Series The Shocker and The Rhino briefly form a team like this, with Shocker as the cold, controlled one, and Rhino as the aggressive lout.