Batman has arguably the best rogues gallery in comics. The Joker, Two-Face, Mr. Freeze, Scarecrow, Catwoman, the list of villains who call Gotham City home is epic. Even the more obscure Batman villains are formidable in their own right and don't get nearly as much credit as they deserve.
Due to the sheer volume of supervillains Batman has faced over his 75 year history, some of his most dangerous and interesting foes have been lost in the shuffle. It's time to give some of these lost bad guys their dues. Because anybody with the nerve to take on Batman has earned our respect, even the Condiment King. No, you know what, especially the Condiment King.
Name: Professor Hugo Strange
Abilities: Genius-level intellect. Master of psychology, chemistry, and biology.
Menace Rating: 8 out of 10 Mad Scientist Clichés
Okay, you know the one villain that's an evil psychiatrist who manipulates people to do his bidding? Or the evil chemist who creates a potent fear-inducing powder? Or the mad scientist who uses injections to turn men into hulking monsters? Alright, so merge all three of those and you get Hugo Strange. Three Batman villains in one and to top it off he knows that Batman is Bruce Wayne! It's astounding that Strange hasn't been featured in the DC Cinematic Universe yet.
Name: Professor Pyg
Abilities: Chemistry expert, preternaturally skilled surgeon.
Menace Rating: 6 out of 10 "DEAR GOD, WHAT DID YOU DO TO MY FACE?!?"
Professor Pyg just wants to make you perfect, that's all. Totally harmless, admirable even. Oh, except by "perfect" he means "lobotomized to follow his will through brain surgery, genital mutilation, mind-altering drugs, and a creepy doll mask permanently attached to your face."
With his army of "perfected" Dollotrons and the rest of his "Circus of Strange," Pyg is a psychotic menace to the people of Gotham. Despite being a relatively new villain to Batman's rogues gallery, Pyg has cemented himself as one of the most disturbing villains in the Dark Knight's lore. Now that's really saying something. It's like being the most stoned person at a Phish concert.
Name: Arnold Wesker/Scarface
Abilities: Criminal genius, good with a Tommy gun.
Menace Rating: 5 out of 10 Mobster Marionettes
Meek, soft-spoken Arnold Wesker is the reluctant host to one of the most effective crime bosses in Gotham. His ventriloquist dummy/alternative personality/abusive partner Mr. Scarface is respected throughout Gotham's underworld, despite basically being a caricature of a 1920's gangster. While Batman could easily pummel Wesker (and, by extension, his puppet), Scarface still causes plenty of trouble in Gotham and inspires enough loyalty in his gang to make the Dark Knight look like the real dummy.
Abilities: Cybernetic enhancements, KGB training, weapons expert, hand-to-hand combat master, has a freakin' gun for a hand.
Menace Rating: 9 out of 10 Soviet Prosthetic Gun Hands
While his name dates him to the Cold War period, KGBeast is one of the most dangerous foes Batman has ever faced. With his combat training, killer instinct, and tactical expertise, he's on equal footing with the Dark Knight. They're so evenly matched, in fact, that Batman thought he straight-up couldn't beat KGBeast mano-a-Batmano.
He locked the Beast in a room instead of fighting him and waited for him to suffocate to death in Batman #420. It was revealed in Batman: Year Three that Batman called the police to pick up KGBeast's unconscious body, but for a while there KGBeast was one of the few foes Batman killed intentionally.