With the recent and critically praised The Batman out, fans have seen another rendition of one of the Dark Knight's most intelligent enemies, but the brooding superhero's rogues' gallery has a handful of other noteworthy characters.
The Riddler is likely among the first villains to come to mind when it comes to intelligence -- as well as the Joker in his own way -- but other villains have proven to be smarter than they let on. They might not be as cunning as the likes of the Clown Prince of Crime, but antagonists like Harley Quinn, Black Mask, and Bane are impressively intelligent in their own rights.
KGBeast
While he's certainly one of the more obscure villains in Batman's rogues' gallery, he was surprisingly effective during his limited run under the spotlight. In the comics, he's been cited as one of DC's most dangerous assassins, and that alone requires being incredibly smart in high-risk fields.
Anatoliy Knyazev's most notable appearance as the KGBeast was arguably in his debut story arc Ten Nights of the Beast, where the villain went on a killing spree that saw him hit nearly all of his 10 targets. He had Batman chasing shadows for much of that story until his eventual defeat, but to accomplish even that much demands a masterful level of strategic prowess.
Anarky
Though Anarky has danced the line of being a supervillain, anti-villain, and antihero, Lonnie Machin's mental maturation can't be understated. He was brought further into the mainstream as one of the side villains in Batman: Arkham Origins, but the character since his inception was an extremist political character with impressive knowledge of philosophy and politics.
His moral alignment is ambiguous and fluctuates, as he has genuinely good intentions but is separated from the heroes for executing methods that are occasionally fatal and terroristic. Nonetheless, to be able to amass the following Anakry did and make Batman work up a sweat at such a young age is nothing short of a demonstration of intellect.
Harley Quinn
Harley Quinn has transitioned into becoming an antihero for DC in more recent years -- even to the point of being a member of the Bat-family -- but she's had respectable intelligence even in her days as a villain alongside Joker. Before becoming ensnared into becoming enamored with the Joker, she was a practicing psychiatrist with expertise in criminology and forensic psychiatry.
In addition to that, she's demonstrated skill as a tactician and escapologist that saw her succeed in capturing and nearly killing the Dark Knight in the Mad Love story (comics and animated series). Her scatterbrained personality often hides that, with her biggest downfall being severe Stockholm syndrome.
Mad Hatter
It's no secret that Jervis Tetch -- the Mad Hatter -- has a glaring Achilles' Heel in the form of his unhinged mental state and extreme delusions of grandeur. His whole personality is based around being stuck in a fantasy world modeled after Alice in Wonderland after being ostracized as a child.
The Mad Hatter fulfills this fantasy using mind control on his victims to force them into indulging his delusions, and his intelligence lies in the technology he uses. His genius-level intellect was focused on neuroscience to develop these dangerous gadgets himself.
Bane
For veteran fans of the superhero, it's well known that Bane has been the mastermind of some of the worst things to ever happen to Batman. However, outside of the comic book source material, Bane has had a good deal of disservice done to his character. Christopher Nolan's The Dark Knight Rises managed to generally redeem his maligned take from the critically panned Batman & Robin by showing him off as a criminal strategist, but it could have arguably gone further.
And even with the deserved acclaim they get, Arkham Asylum and City were major letdowns for Bane. But, as demonstrated in his successful plan to metaphorically and physically "break the Bat," Bane is meant to be an intellectual equal to Batman on top of his brawn.
Black Mask
Essentially serving as the evolution of organized crime back when the likes of Carmine Falcone and Salvatore Maroni ruled Gotham City, Black Mask is an imposing figure with his own merits. Even with the titular black mask fixed to his face, Roman Sionis isn't the flashiest of Batman rogues, but the empire he's built with the likes of the Dark Knight running around takes intelligence.
Black Mask managed to be the top crime lord in the city for a spell, with it taking a rampage by Red Hood to bring it back down -- as seen masterfully adapted in the animated Batman movie Under the Red Hood. What's arguably keeping him from reaching greater heights is his infamously uncontrollable temper.
Penguin
He's certainly one of the most popular and recognizable villains in Batman's mythos -- and even more so thanks to Colin Farrell's portrayal in The Batman -- though people don't generally associate him with being especially smart. Being looked down, stepped on, and humiliated is even a recurring theme whenever the Penguin is thwarted.
However, in a similar case to Black Mask, the stake he planted in Gotham's underworld took a particular degree of cunning. Being a successful mob boss in the "age of the freaks" is no easy feat, and in continuities like Earth One, he even managed to manipulate the city's politics into ruling it as mayor.
Catman
Characters intended to be the "dark mirror" of Batman eventually became played out in the comics, but Catman has been shown to measure up to some of DC's most proficient hand-to-hand combatants and strategists.
Taking a look at a villain with the name and costume of "Catman" might not do him any favors for the uninitiated fan, but his martial arts prowess and athleticism are on par with the likes of Bronze Tiger. Likewise, he's applied his own genius to being an expert-level hunter and tracker.
Calendar Man
Calendar Man has had a dramatic -- and a much-needed -- reinvention since his early days in DC Comics history. He started in the over-the-top campy days of the comic book industry, looking as ridiculous as his name sounds. However, in Jeph Loeb and Tim Sale's revered The Long Halloween, he got a makeover as Hannibal Lecter-style serial killer.
Julian Day never takes up too much of the spotlight and often appears rather subdued. That's by design, though, as he also has a canonically genius-level intellect that he uses as a master manipulator to elude the likes of the World's Greatest Detective himself.
Deacon Blackfire
He's received a slight mainstream bump since appearing as a deranged villain in a side mission for Rocksteady's Batman: Arkham Knight, but Deacon Blackfire's comic book appearances suggest something far more consciously sinister.
In his most famous and debut story arc The Cult, he's a cult leader who manages to garner a massive following of Gotham City's downtrodden homeless population in the sewers with the promise of fighting back against their criminal oppressors. However, it was all a fraud to use them for wanton violence and rule the city. Blackfire is certainly smart and knows what he's doing, as he's perfected his brand of con artistry to manipulate peoples' minds.
