In 2003, Adult Swim released an animated series directly inspired from (and directly animated on top of) the old action-cartoons of Hanna-Barbera's golden age and Silver Age comics. This included classics such as Fantastic Four, Scooby-Doo, and, of course, Jonny Quest. And while this series did a great job of emulating the feel and characters of this series, it didn't take long before it crafted an identity all of its own and created characters and actions that completely rivaled its predecessors and anything shown today.

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That series is The Venture Bros., a series about the titular Venture family who try to navigate their fantastical/sci-fi world while clashing with its various villains. And while the heroes are certainly a core element of the story, it's the world, personalities, and inherent camp of its villains that truly take Hanna-Barbera's old formulas and perfect them as the series' own.

10 Augustus St. Cloud

Augustus St Cloud

Augustus St. Cloud may not be the most ambitious or even most competent villain; but when it comes to hating a rival at a deep, personal, and malevolent level, St. Cloud is one of the best. His arch-nemesis is Sir Billy Quizboy, Dr. Venture's best colleague and an old, quiz bowl rival of St. Cloud's who got caught in a cheating scandal.

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Wanting to take revenge on Billy for robbing him of his quiz bowl career as well as a few key bids on eBay, Augustus St. Cloud joined the Guild of Calamitous intent to gain their arching privileges and now dedicates his life to trying to taint the various pop culture symbols that a hardened nerd like Billy worships.

9 Baron Ünderbheit

Baron Underbheit

Baron Ünderbheit may have fallen far from grace after being usurped by Girl Hitler; but during his tenure as one of Dr. Venture's most vengeful arches, he was a tyrannical dictator who ruled and fought with an iron underbite.

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He and Rust actually knew each other in college; but after Rusty seemingly blew off his lower jaw during a failed lab experiment, the Baron swore vengeance on Venture and did his best to torment his family whenever they came close to his home country of Ünderland. His most recent exploits have him be one of the key agents in Phantom Limb's Revenge Society.

8 Copycat

Copycat

Copycat may not be the kind of world-conquering villain that everyone should fear, but he's still pretty despicable all the same. When Wide Whale was trying to ruin The Monarch's life, Copycat helped frame The Monarch for vandalizing the Venture's apartment to seed distrust in Dr. Mrs. The Monarch.

Later, he arranged a big heist to steal Dr. Venture's new teleporter where he brought in The Monarch and various other small, time villains to help. In actuality, Copycat was just using them as pawns to take the teleporters for himself, though he quickly had his comeuppance when he seemingly got caught in a helicopter crash.

7 Dr. Z

Dr Z

Dr. Z is a hero to various members of the Guild of Calamitous Intent. That is to say that, between his grandiose monologues and use of giant robots, Dr. Z is a villain among villains. As one of Jonas Venture's greatest rivals and the old, arch-nemesis to Action Johnny, Dr. Z had a gilded career as a cruel and tyrannical villain who brought fear to both his underlings and enemies alike.

While he seemed to be enjoying retirement, he was later brought back into the Guild to help run the new Council after The Sovereign betrayed the Guild.

6 The Sovereign

The Sovereign

While it's sad to hear that David Bowie wasn't actually a shapeshifting, supervillain, The Sovereign still carried himself with the same fusion of stoicism and panache that the pop star was famous for. Once a down-on-his-luck villain, The Sovereign eventually worked his way up through the evil world to eventually run the Guild of Calamitous Intent and make it the large organization that it is today.

He famously convinced O.S.I. that S.P.H.I.N.X. was responsible for the tragedy on Gargantua-1, initiating the Pyramid Wars, and plotted to kill all of his enemies in one fell swoop in "All This and Gargantua-2," where he tried to both cover his tracks from O.S.I. as well as get out of his debt to The Investors. It's implied that he was accidentally shot when he tried to fly away as an eagle.

5 Wide Whale

Wide Whale

Wide Whale is an homage to the types of mafioso-esque villains that were popular in superhero comics during their early years. After getting into a whale experiment gone wrong, he became part whale and has outfitted his entire crime syndicate to fit that theme. He uses money, manipulation, and threats to take over a huge section of New York, including its superheroes, the Crusaders Action League.

He's been trying to force Dr. Venture to work under his payroll ever since he moved to New York and spent Season 6 trying to sabotage The Monarch's life to avenge his brother that The Monarch presumably killed.

4 Red Death

Red Death and His Wife

Few villains in any piece of fiction can so naturally and dramatically strike fear into the audience's hearts like Red Death. Celebrating villainy to its full capacity, Red Death was the type of villain who just wanted to wreck things and slay his enemies.

Though he's calmed down in old age, he still brings back his inner psychopath whenever he does hunt down his current assignments and accompanies each arch with some monologues wonderfully voice worked by Clancy Brown. He was one of the conspirators behind the Movie Night Massacre, though he admits to not knowing what really happened, and now operates as a member of the Guild's new Council.

3 Dr. Mrs. The Monarch

Dr-Mrs-Monarch

While The Monarch may treat Sheila like a glorified sidekick, she's the real brains behind his operation who actually builds his various weapons against Dr. Venture and orients the henchmen for their mission. In her early years, Dr. Mrs. The Monarch was once a Catwoman-like thief called Lady Au Pair who was accompanied by two "Murderous Moppets."

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She'd later become the #2 to Phantom Limb and later The Monarch. While this would seemingly dilute her reputation, she was still entrusted as one of the most best villains around to help rebuild the Council.

2 Phantom Limb

Phantom Limb vs Fantomas

Phantom Limb is the very definition of a comic book villain. He was once a brilliant scientist who got his eponymous "phantom limbs" after a science experiment gone wrong. Believing that because his grandfather, Fantômas, once presided over the Guild that he should run it, he'd go on to build one of the strongest villain empires around and capitalized on The Monarch's wedding to try and usurp the then-current Sovereign.

When that failed, he still managed to work his way from a prison cell to create another villain group, The Revenge Society, to exact vengeance on Dr. Venture while simultaneously trying to earn back his place in the Guild. Given that he's now part of the new Guild, he's succeeded.

1 The Monarch

The Monarch And Dr Mrs The Monarch

As Dr. Mrs. The Monarch put it, The Monarch has more hate at the tip of his finger than most villains have in their entire lives. A villain who just wants to arch for arching's sake, The Monarch has an unbridled albeit ill-explained vendetta against Dr. Venture that propels him to obsessively and destructively stalk the man, with or without the henchmen army or giant robots of a villain empire.

He certainly has the laugh and eccentric monologuing down pat; and despite his perceived incompetence, he has the kind of grit and perseverance that only a true villain could have, especially if they're brave enough to try and threaten people dressed as a giant butterfly.

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