Everyone knows Batman is a hero with a code, a major rule by which he operates in the field. That code? Thou shalt not kill, firmly believing that if he is to take on the criminal underworld, the caped crusader must act above the character of his super villain counterparts.

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However, it wasn't always that way. Originally, The Dark Knight had no misgivings about offing his enemies – as evidenced by some of his early missions in Detective Comics. Please note this list only deals with Bruce Wayne as Batman (the one who actually professed such a code). This list does not include Thomas Wayne or other Batman's like Azrael or Damian Wayne who never claimed to be above killing.

15 Detective Comics #27: Punching Man Into Acid Vat

Batman's first kill actually occurred during his first outing as the caped crusader. With Detective Comics #27, the dark knight said hello to the world, debuting as an aloof billionaire friend of Commissioner Jim Gordon who secretly fights crime as a costumed vigilante.

Enter a confrontation with corrupt businessman Alfred Stryker who assassinated his own business partner in order to seize control of the Apex Chemical Corporation. During the confrontation, however, Batman punches Stryker off a platform, sending the man headfirst into a drum of acid. Batman: Day One: Murder.

14 Detective Comics #29: Burns Dr. Death

Dr. Death burns alive in his lab in Detective Comics #29

Just like with his debut outing, Batman killed yet again in Detective Comics #29, an issue introducing the caped crusader's very first super villain: Dr. Death aka Karl Helfern. Death, a mad scientist, created a biological weapon in which he used to hold the rich people of Gotham for a hefty random.

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That is until he ran into the likes of the Dark Knight. Thwarting Death's band of henchmen, Batman sets the laboratory on fire, immolating Hellfern in the process. Batman watches as the scientist is burned to a crisp.

13 Detective Comics #30: Batman Snaps A Man's Neck

Batman was just offing baddies left and right in the old days and this instance was one particular brutal kill made by the Dark Knight. The issue? Detective Comics #30.The situation? A man named Mr. Jones has been mysteriously murdered and it's up the Caped Crusader to find out whodunit.

So what happens? Batman learns a man named Mikhail is behind the killing, a man who Batman tracks down and swiftly punishes with a hard kick to the back of the neck (and breaking it). Those who do evil beware...

12 Detective Comics #32: Mad Monk

Batman shoots into a coffin occupied by Mad Monk

This event occurs at the end of the two-part adventure where Batman chases his new enemy, the monk, into the vast terrain of Hungary.

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Deep in the heart of the Carpathian Mountains, he discovers a cave wherein he meets woman named Dala. Turns out Dala is a vampire, revealing the truth about Batman's target: so is he! Eventually, Bats comes upon the coffin of the monk himself where he shoots him with a silver bullet.

11 Detective Comics #37: Pushes Man On Sword

A man falls on a sword in Detective Comics 37

In this doozy of an adventure, Batman finds himself up against an ego-maniacal rich dude who loves his monocle just as much as he does throwing swords at superheroes.

Batman dodges the attack, of course, springing forward to punch the villainous blue blood in the jaw. The man falls on his own sword, taking the blade right through the back of the head.

10 Batman #1: Hanging Giant

Like his debut in Detective Comics #27, Batman's first outing under his own comic book series resulted in the dark knight breaking his moral code. Yes, the earlier "bats books" were particularly brutal, DC adding in the no-kill rule later on as the character continued to develop.

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In this first outing, Batman finds himself against the likes of Hugo Strange who has constructed a super serum which he has injected into escaped mental patients from Arkham Asylum. Wayne finds himself up against one particularly super-charged specimen who he dispatches with a good old fashion rope, hanging the man by the neck until dead.

9 Batman #1: Hugo Strange

Hugo Strange as Batman

After taking out the super serum-powered giant, the Dark Knight sets his sights on Hugo Strange himself, tracking the mad scientist down from his batcopter.

After finally locating Strange, the Caped Crusader rams his vehicle into the man. Strange splats on the front fender and never moves again.

8 Batman #420: Buries KGBeast Alive

Batman leaves KGBeast to die.

Right from Reagan-era Cold War politics comes this story about Batman facing off against a Russian super soldier named KGBeast, who has been unleashed on Gotham to assassinate several high profile politicians.

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Batman eventually catches up with KGBeast, igniting a skirmish that takes them both into to the sewers of Gotham. There, Batman manages to trap the Russian in a metal chamber, leaving KGBeast to starve to death in the depths. This was obviously retconned later as KGBeast eventually returned in the post Rebirth era, but this still counts as a bat kill nonetheless.

7 Batman #425: The Scrap Yard

batman kills batman 425

Jim Gordon has been kidnapped by drug-smuggling gangster Jose Garzonas who blames Batman and Robin for the death of his son. Using Gordon as bait, Garzonas lures the dynamic duo into a junkyard where he holds Gotham PD's head honcho at gunpoint.

However, Batman and Robin free Gordon as the fight ensues, the Caped Crusader drawing Garzonas to a pile of cars thereafter. Once the trap is set, the Dark Knight tips the stack of junk vehicles and crushes the Garzonas flat.

6 Red Rain: Kills Dracula

Yes, the Dark Knight actually faced off against the Prince of Darkness in this epic maxi-series by Doug Moench and Kelley Jones (1991). Dracula, who's been terrorizing Gotham and turning innocent civilians into vampires, squares up with the Caped Crusader in a clash of titans.

Since there's only room for one lord of night in this town, the two battle it out for the soul of the city. Batman struggles at first since Dracula is technically a meta-human, but eventually the dark knight gains his whits, impaling the blood sucker on the shard of a broken tree. Batman 1 - Vampires 0.

5 Bloodstorm: Stakes Joker

batman-red-rain-bloodstorm-crimson-mist

Keeping with the Red Rain arc for a moment, Bloodstorm tells of what happens when the Clown Prince of Crime gets turned into a vampire then takes over the late Dracula's hordes of undead.

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As usual, it's up to Batman to stop his arch nemesis who is now empowered with all of the supernatural abilities of a night stalker. However, it all comes to a head when Batman stakes Vampire Joker through the heart, ending his reign of terror at long last.

4 Justice League America: The Nail

Another "What-If" tale created by Alan Davis and Mark Farmer, Justice League: The Nail tells the story of a world where John and Martha Kent suffer a flat tire while driving down the road, causing them to miss the crashed Kryptonian spaceship and thus establishing a world without Superman.

Many years later, Batman's arch enemy, Joker, has once again sprung the dangerous criminals of Arkham Asylum. As usual, there to thwart him is the Caped Crusader, along with sidekicks Robin and Batgirl. However, upon acting against Batman's orders, Robin and Batgirl are killed by the Clown Prince of Crime, provoking Batman to outright murder Joker in an act of bloody revenge.

3 All Star Batman And Robin: Burns Criminals Alive

Batman makes out with Black Canary on a dock in the rain with a fire blazing after them

Perhaps one of the most outlandish kills in Batman history, the Dark Knight did indeed burn a whole host of criminals alive (and had sex next to their remains but that's a tale for another time).

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The whole thing goes down in All Star Batman and Robin, The Boy Wonder – a version which depicts the caped crusader as an abusive, blood-thirsty vigilante who verbally harasses his sidekick and responds to crime with extreme prejudice. One such example? A group of criminals steal vats of bleach from a shipping container... and the Dark Knight responds by lighting them up a literal blazing inferno.

2 Final Crisis: Batman Shoots Darkseid

Batman shoots Darkseid

This one doesn't occur right away but is still attributed to Bats. Grant Morrison's limited series sees the return of the lord of Apokolips himself, Darkseid, who once again seeks to enslave the universe with his demons.

Taking him on are the heroes of DC, but it's actually the Dark Knight who ultimately does the demon king in. How? By blasting Darkseid with a radion bullet... of which eventually kills the apokoliptian upon dealing a mortal wound. As far as DC goes, chalk this up as a big win for the caped crusader.

1 The Hunt For The Beast: Leaves KGBeast To Die... Again

KGBeast - DC Comics Batman

In another run in with the Russian assassin, KGBeast, this battle takes the Dark Knight to the snowy fields of the arctic. Hired by Bane to kill Nightwing, KGBeast is thwarted by the caped crusader.

After a bloody battle, KGBeast lays wounded on the ground after suffering from a broken neck. A break dealt by the Dark Knight no less. So what does Ol' Bats do? Tells him to find "his own damn help." How cold...

NEXT: Batman: 5 X-Men Bane Can Defeat (& 5 He'd Lose To)