Big Bad Duumvirate / Western Animation

• Adventures of the Gummi Bears in later seasons have Duke Igthorn and Lady Bane as the recurrent villains, often appearing in the same episode with Igthorn's crush on her as a Running Gag.
• Avatar: The Last Airbender:
  • Book 2 ends this way, with Princess Azula and Long Feng teaming up to perform a coup on the Earth City capital, Ba Sing Se. However, from the beginning, both were planning to betray the other with Azula planning to take it for the Fire Nation and Long Feng planning to take control from the Earth King and have a more iron-fisted ruler for the Earth Kingdom. When the coup is complete, Azula turns Long Feng's own men against him, having impressed and terrified them with her ruthlessness and cunning, ending it with a Breaking Speech to her defeated rival.
  • In Book 1 of The Legend of Korra, Amon is the direct big bad by lying, exaggerating, and manipulating non-benders to his cause by fabricating certain cases against benders, but Tarrlok inadvertently helps this along by mobilizing task forces against Non-benders, fueling their wrath against Benders. The real issues and greater scope enemy of book 1 is the conflict between benders and non-benders; but both brothers (perhaps unwittingly on Tarrlok's part, but regardless) are escalating the violence in the city, causing a Civil War in the process.
  • In Book 2 of The Legend of Korra, it is possible that Vaatu and Unalaq were this rather than Unalaq being The Dragon to Vaatu. While Vaatu was far more powerful than Unalaq, he was largely helpless for most of the season until Unalaq's machinations allowed him to escape, and Unalaq did so out of his own ambition rather than any loyalty to Vaatu. This comes across most strongly in the finale, where they merge into the Dark Avatar and are treated as a single threat, rather than Vaatu overriding Unalaq (or the other way around) like most similar situations.
• Ben 10 did it several times in all three series:
  • Big Bads Vilgax and Kevin 11, respectively from season 1 and 2 of the original series, teamed up at the end of season 2 in an attempt to take the Omnitrix from Ben. Kevin's betrayal eventually caused the alliance to fail and led to both of them being trapped in the Null Void.
  • Vilgax teamed up with Albedo in the Alien Force finale in a new attempt to take the Omnitrix. Though the alliance was successful, Vilgax then betrayed Albedo, and Ben was able to defeat him alone.
• In the 2006 revival of Biker Mice from Mars, the main antagonists are a race of cat-like aliens called the Catatonians, led by Hannibal T. Hairball and his Dragon-in-Chief Cataclysm, as well as a Corrupt Corporate Executive named Ronaldo Rump. The Catatonians are invading Mars and try to stop Vinnie, Throttle, and Modo from rescuing Stoker so he can make a new regenerator that can be used to end the drought on Mars, while Ronaldo Rump wants Stoker to build a new regenerator because the one he has that he uses for his land development schemes is running low on power.
• Carmen Sandiego has the five leaders of V.I.L.E. — Coach Brunt, Professor Maelstrom, Countess Cleo, Doctor Bellum, and Shadow-san — who run the organization by committee, with no one member appearing to have seniority over the others. After Shadow-san defects at the end of Season 1, the other four spend most of Season 2 trying to fill his vacant seat, ultimately settling on Roundabout, their Double Agent in British intelligence.
• Season 3 of Castlevania reveals that Carmilla, The Starscream of Season 2, rules over her fiefdom jointly with her sisters Morana, Striga, and Lenore. While Carmilla herself is recognized as the nominal leader of the group, each of them as their own area of expertise and run things by committee.
  • Castlevania: Nocturne has the alliance between Countess Erzsebet Báthory, the self-proclaimed Vampire Messiah who intends to lead the vampires in conquering the world, and Abbot Emanuel, who acts as Erzsebet's Forgemaster in exchange for her using her forces to crush the French Revolution, which he sees as a threat to the church. Each is planning to betray the other as soon as they're no longer needed and by the end of the season, Erzsebet has proven herself Eviler than Thou, having completely broken Emanuel's spirit and reducing him to her servant.
• In seasons 4 through 6 of The Fairly OddParents!, Anti-Cosmo, the leader of the anti-fairies, and HP, the leader of the pixies, seemed to have equal claim to the title of Big Bad. This is especially notable in season 6, where the two never appeared without the other. Which is an odd pairing considering HP wants to impose order and is teaming with someone who obviously doesn't share that goal.
• Sarmoti and Blake from Father of the Pride are both antagonists for Larry, the former being both personal and in business and the latter only being in business.
• In the Pilot Movie for Foster's Home for Imaginary Friends, House of Bloo's, Terrence and Duchess team up around the second act to get rid of Bloo once and for all.
• Xanatos and Demona for the first season of Gargoyles and about 1/3 of the second season. At that point their goals and methods become too divergent, and Xanatos teams up with the heroes to stop Demona from turning the population of New York to stone.
• In a case of What Could Have Been for the third season of G.I. Joe: A Real American Hero, if it had remained under Sunbow, the plan was for the Crimson Twins, Tomax and Xamot, to take over what was left of Cobra as "The Coil" and take what they saw as its best parts in a less military, more "criminal" direction.
• Hazbin Hotel: As a general rule, Hell's Overlords work alone even if they are not hostile to one another. Vox, Velvette and Valentino, a triumvirate of Overlords that governs some of Hell's most influential industries (television, fashion and pornography, respectively), is collectively known as "the Vees". They use the same building as their headquarters and regularly hang out together when they're not working on their own businesses. Whereas the rest of the Overlords (with the possible exception of Alastor) try not to upset the status quo too much (since that would risk extermination at the hands of Heaven), the Vees have no such qualms, and constantly hunger for more power for themselves. It's implied that this is because they are among the youngest of the current Overlords, and as such lack maturity and caution (not to mention respect for their fellow Overlords).
• Infinity Train: Special Agent Mace and Agent Sieve were Villains of the Week in Book 1, but come Book 2, they're the primary recurring threat relentlessly hunting Mirror Tulip as she attempts to escape the train. Though Mace is the more senior and commanding of the pair, Sieve is shown to be more adept at manipulation and proves to be just as ruthless when pushed enough.
• The Almighty Tallest of Invader Zim, whom the titular Villain Protagonist serves. Normally it'd just be a single Evil Overlord, but since Red and Purple are the same height they're the joint rulers of The Empire (though Red seems to be a bit more competent).
• Lex Luthor and Braniac during the Cadmus Arc of Justice League Unlimited.
• Kulipari: An Army of Frogs has Lord Marmoo and Queen Jarrah, the former of whom teams up with the latter so she can destroy the Veil, and he can take over the Amphibilands. Jarrah, despite her hatred of Marmoo, continues to work with him, as she needs him to kill the Turtle King and assist her army in terms of size and strength.
• Metalocalypse:
  • General Crozier and Cardinal Ravenwood could be considered the first season's Big Bad Duumvirate (with the Metal Masked Assassin as their Dragon). Mr. Selatcia is not happy to learn that the two are acting behind his back and gruesomely murders Ravenwood while wiping Crozier's memory.
  • In season 2, the Metal Masked Assassin and Edgar Jomfru act as the season's Big Bads when they form the Revengencers, appearing in several episodes of the season as they scheme to get revenge on Dethklok. Could possibly be considered a triumvirate after they establish an alliance with Lavona Succoboso in the season finale. By the end of the finale Jomfru is captured by the Klokateers while the Metal Masked Assassin barely escapes after brutalizing Charles. Lavona's fate is left uncertain.
  • In season 4, the Metal Masked Assassin has formed a new Duumvirate with Magnus Hammersmith, who bides his time to get revenge on Dethklok while earning their trust. This culminates with Toki and Abigail being stabbed and kidnapped in the season finale as Magnus screams "REVENGE HAS COME!".
  • In The Doomstar Requiem, after Magnus objects to the Metal Masked Assassin killing Ishnifus Meaddle (who sacrificed himself to facilitate Dethklok's escape from the Revengencers), the latter decides that Magnus is no longer of any use and impales him on a metal rod, meeting his end after Dethklok returns and obliterates him after being empowered by the Doomstar. Magnus escapes before the building crumbles, and survives his injuries long enough to kill himself after the event he just witnessed makes him realize he was the villain instead of the hero.
• Moog Magister and Hector Sinestro in Monster Allergy.
• My Little Pony:
  • My Little Pony 'n Friends: "The End of Flutter Valley" has the witch Hydia and Queen Bumble share the spotlight as antagonists. The two mostly work independently, but do so under a common plan and with the intention of coordinating their strikes in order to lure the flutter ponies into a trap and share the benefits of taking the Sunstone from Flutter Valley.
  • My Little Pony: Friendship Is Magic: The final season has Grogar recruit all of the non-reformed big bads from previous seasons — Queen Chrysalis from seasons 2 and 6, King Sombra from season 3, Tirek from season 4, and Cozy Glow from season 8. It's eventually revealed that Grogar was actually Discord in disguise as part of a convoluted plan to boost Twilight's confidence, while Chrysalis, Tirek, and Cozy Glow stab him in the back and go on to become the true final antagonists of the series as a united force.
• LEGO Nexo Knights generally features an alliance between Monstrox and Jestro as its lead villains.
• A couple from OK K.O.! Let's Be Heroes:
  • Lord Boxman—who's arguably the Big Bad of the series (certainly of Season 1, and is the most consistent antagonist the heroes face)—teams up with his client, Professor Venomous, midway through Season 2 in a permanent alliance to co-run Boxmore and antagonize the Bodega heroes together. Even working together, they're still not the only major threat to the heroes, making them a Duumvirate that's also part of a Big Bad Ensemble.
  • In the series climax, T.K.O. and Shadowy Figure each perform a Split-Personality Takeover on their respective hosts, K.O. and Professor Venomous^note Well, Shadowy claims that his was a Split-Personality Merge, but it's implied otherwise, and "Shadowy Venomous" convinces T.K.O. to team up with him, ousting Boxman when he protests their actions. It lasts for a couple of episodes until Shadowy Figure makes it clear that, despite them technically being father and son due to the relationship between their hosts, he didn't really care about T.K.O. and was just using him to get more power; T.K.O. subsequently beats Shadowy out of Venomous and destroys him for good.
• In the second season of Scooby-Doo! Mystery Incorporated, Professor Pericles and Mr. E serve as this in a downplayed example. While the two appear to be equal in power, Pericles is actually the dominant force of evil. Mr. E ends up pulling a Heel–Face Turn as he realizes the evils he and his compatriots are sinking to, while Pericles stops treating Mr. E with any resemblance of respect and properly asserts his authority as the season draws to its' close.
• South Park:
  • Eric Cartman manages to form one with Cthulhu in the "Coon & Friends" trilogy, where the two proceed to destroy everything the former doesn't like.
  • Cartman forms another one with the Record Producer in Season 18's two part finale, which leads to Cartman becoming the Final Boss of that season.
  • Pi-Pi and ManBearPig are this for The Streaming Wars. They work together to monopolize the streaming (water) services and draining water in Colorado to replace with urine, while killing anyone who stands in their way.
• In Steven Universe, the Homeworld Gems are ruled by a group called the Great Diamond Authority, which, at present, consists of Blue Diamond, Yellow Diamond, and White Diamond, though White Diamond holds more authority than Blue and Yellow with both of them fearing her. Older versions of their Arc Symbol also included a Pink Diamond, but it's conspicuously absent from modern Gem Machines. We later discover that there was a Pink Diamond and Rose Quartz shattered her... Or so everyone thought, until Steven finds out while in Pearl's Gem, he sees that the Rose Quartz that shattered Pink Diamond was actually Pearl, and that the REAL Rose Quartz never shattered Pink Diamond; she WAS Pink Diamond. ALL ALONG.
• Teenage Mutant Ninja Turtles:
  • Teenage Mutant Ninja Turtles: Fast Forward, the two main villains were invading alien Sh'Okanabo and corrupt C.E.O. Darius Dun. Despite different goals and storylines, they established a resource-sharing relationship, where Darius gave Sh'Okanabo the stolen plans for nephew Cody Jones' time window, in exchange for the assistance of the turtle clones Sh'Okanabo had created.
  • In the 1987 cartoon, the conventional opinion seems to be that Shredder is The Dragon and Krang is the Big Bad, but that could easily be just because The Dragon is a much better-known trope than Big Bad Duumvirate. There is no question that Shredder sees himself as a Big Bad in an equal partnership with Krang, and it usually seems as if most of the characters agree (Krang may be the only one who sees himself as Shredder's boss). And in an alternate history where the villains succeed in taking over the world, who is the natural choice for the position of Emperor? Hint: The episode isn't titled "Krangville."
• The Transformers:
  • The Quintessions, being many villains that work together, each with multiple personalities. During G1's third season, the Autobots had to contend with the Decepticons and the Quintessions (who sometimes worked together to achieve their own mutually exclusive ends).
  • The short-lived fourth season had Galvatron in a tenuous alliance with the Nebulan overlord Lord Zarak.
• The Big Bad of the second season of Wakfu is initially set up to be Rushu, the king of Shushu until Qilby becomes another Big Bad of the season and the two team up.

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