#3. Batman Pushes a Dude into a Sword (Detective Comics No. 37, 1940)
In this issue, the villain makes the deadly mistake of throwing a sword at Batman. The only thing that this accomplishes is getting on the Dark Knight's nerves. The sword becomes lodged in a door and a supremely pissed-off Batman starts walking toward the villain, who trembles and begs for mercy, sensing the fate that's in store for him.
"Have mercy! My monocle needs me."
What sets this particular Bat-murder apart is how deliberate and easily avoidable it was: Batman isn't in a life-or-death situation here, and the guy is completely unarmed and clearly prepared to give himself up. Batman had to close the door, walk across the hallway and position himself at the other side of the formerly monocled villain ...
Batman punched him so hard that it just disintegrated.
... and then hit him with enough force to send him flying into the sword and cause it to stab the back of his neck.
"This is exactly how that hooker died at Jon Favreau's bachelor party."
So we guess that the lesson here, kids, is that if you throw a sword at Batman, you'd better make damned sure you don't miss.
#2. Batman Locks a Villain Underground and Starves Him (Batman No. 420, 1988)
The KGBeast was a short-lived Batman villain sent to America by the Soviet Union to kill everyone involved with the Star Wars defense program, including President Reagan. When we say "short-lived," we don't mean that the writers stopped using him once the cultural references became outdated five months later -- we mean that Batman locked the dude away without food and abandoned him.
The Soviets were notoriously fond of S&M.
After being outmatched by the KGBeast for three straight issues, Batman finally manages to break his bitchin' arm-gun and lures him into the sewers, where they reach a dead end. The KGBeast offers a final challenge to the Dark Knight Detective: beat each other with pipes until a victor emerges. Batman promptly tells him to eat a dick.
"I left my bludgeoning pipe at home."
Batman stands outside the room and coldly explains to the villain that he simply can't be bothered to fight him, as he slowly closes the steel door behind him ...
"Also, my DVR is broken and Homeland is about to start, so ..."
... then barricades it with a nearby stack of planks, perfectly jamming it, and quietly leaves KGBeast fruitlessly banging on the door with his one good hand.
Batman, not grasping how doors work, shores up the hinges.
Batman calmly walks away, leaving the guy to starve or asphyxiate behind a steel door. Once he makes it back to the surface, a CIA agent congratulates Batman on stopping the KGBeast before he could get to Reagan. Then the agent (who had previously told Batman that if the villain was caught alive, they'd have to turn him over to the Soviets) asks where KGBeast is, and we're treated to this gem of a response:
This man has the shortest refractory period in history.
In later comics, a different writer clarified that Batman told the police to retrieve the villain before he could die, and the KGBeast later broke out of prison, which doesn't even make sense with this story, because he would've been sent back to Russia right away. However, the intent of this issue is clear: proving that Batman is indeed a bad enough dude to save the president. Even if it means starving people to death.
#1. Batman Lets Some Thieves Burn to Death ... as He Gets Laid (All-Star Batman and Robin No. 7, 2007)
Note: This following horrific sequence of events becomes much funnier if you imagine Adam West doing it.
So Batman starts this particular issue by swooping down on a bunch of armed thugs stealing a shipment of ... bleach, for some reason. Apparently the Gotham City black market has some serious issues with spilling wine. Not satisfied with scaring the bodily fluids out of them, our "hero" grabs a bottle of flammable bleach, combines it with some thermite he presumably carries in his utility belt for this very purpose and flings it into the crowd.
"Molotov cocktails are only for women and communists!"
Apparently the thieves had been playfully splashing bleach at each other with Super Soakers before Batman arrived, because Batman's dirty bomb is enough to instantly ignite the whole sorry lot.
"Who knew that a spontaneous bleach-balloon fight could go so horribly awry?!"
Now the thugs are scared shitless and burning to death. They are not a threat anymore. They couldn't attack Batman even if they wanted to ... and yet he still feels the need to mercilessly beat the crap out of every single one of them. At this point Batman's fellow Justice Leaguer, the Black Canary, stops by and looks on as Batman needlessly kicks a burning criminal's face into the asphalt. Rather than stopping him, she decides to watch him some more and comment on how aroused this is making her feel. Seriously.
"Krunch hurkk" -- that's the sound of Batman's moral high ground disappearing.
So this is the part where they turn off the fire and tie up the criminals for the authorities to retrieve them, right? Nope: Instead, they lie down on the wet cement and start jumping each other's bones directly in front of the heap of burning flesh that was once a gang of bleach thieves.
Turns out rendered human fat makes excellent lube.
Now, this issue is part of Frank Miller's insane "I'm the goddamn Batman" series, but still -- holy shit, DC. Hopefully you paid Miller's salary in therapy sessions.
For more reasons Batman isn't so squeaky clean, check out 5 Reasons There Must Be Corpses Buried Under the Batcave and Why Batman Is Secretly Terrible for Gotham.
If you're pressed for time and just looking for a quick fix, then check out 6 Important Things That We Built On Top of Supervolcanoes.