Action Comics: In Grant Morrison's run that launched the New 52 universe, Mr. Mxyzptlk is a 5th Dimension imp who works as the Court Jester for the land of Zrfff. He entertains the kingdom by annoying the heroes of several worlds, including Superman, and letting Zrfff watch. Enraged with jealously over Mxyzptlk's popularity and success, the kingdom's other jester, Vyndktvx, decided to uses his powers to secretly make Superman's life a living hell before eventually killing him, even assembling an "Anti-Superman Army" — and do it all before Superman ever met Mxyzptlk in the first place. Of course, Superman has no idea who he is, but Vyndktvx holds him responsible for Mxyzptlk's success because the kingdom really liked how he was the only hero to best Mxyzptlk.
Bane: I'd kill for anything. I'd kill to silence a grating voice. To darken the light of the eyes that dared to look at me.
One◊ of the Tales of Arkham comics features the Penguin, and uses this to explain why a criminal like him belongs in Arkham despite his relatively sane methods and motives. In the story, after a chef is seen laughing in the Penguin's general direction while he is eating dinner: "Maybe it was just a coincidence that the chef laughed while looking in the Penguin's direction. Maybe he just happened to think of something funny, some joke he'd heard the other day, while glancing around the room. Maybe there was nothing malicious about it at all. But in the end... it really didn't matter. And so they ate their dinner, and enjoyed their evening, and the Penguin never said a word about the chef who'd laughed. But a few days later, that building had a new owner, and the restaurant was forced to close, its employees all fired. And the day after losing his job, the chef found that his girlfriend had been suddenly deported to Romania and his best friend arrested for child pornography despite his insistence that he was framed. The day after that, a new tenant moved in next door and begin blasting their stereo at all hours of the day and night. The landlord stopped taking his calls. The church he attended was closed for fumigation, after a bizarre infestation of killer bees. The park where he liked to sit and read was annexed and bulldozed. And then the chef, who was a recovering alcoholic, woke one morning to find that a 24 hour liquor store had opened across the street from his apartment. Less than two months after he'd crossed paths with the Penguin, a night janitor found the chef in a bus station restroom. He'd hanged himself."
Penguin does it again in his miniseries Penguin: Pain and Prejudice. At a party, a guy bumps into him and starts to call him a fatass before he sees who it is and begs for forgiveness. Penguin responds by having him fired from his job, burning down his apartment, cutting the brakes on his parent's car and having his girlfriend infected with what's heavily implied to be AIDs.
Season 8 of Buffy the Vampire Slayer gives us Monroe. Disagree with your former teachers on what it means to be a werewolf? That's okay. Just slaughter most of the Buddhist monks of the monastery they live in.
Abundant in various Chick Tracts, mostly by God Himself. However, one that stands out is "Fairy Tales?" In this Tract, a young boy goes on a killing spree, burns down his school, and is sent to juvenile hall. After his release from juvie, he becomes one of the FBI's top ten most wanted who is eventually arrested, tried, executed, and sent to Hell for his crimes. What exactly caused all of this to happen to him? The fact that Santa Claus, the Tooth Fairy, and Easter Bunny aren't real.
In Death of the Family, Joker punches Harley Quinn in the face. He claims that it is because she had hubris on her face.
The Kingpin likes to think of himself as an intelligent man who doesn't let emotions get the best of him but in truth, he'll overact massively to mild slights. An underling attempts to point out how a vendetta against Daredevil is bad for business and the Kingpin has his legs broken. An innocent waiter makes the mistake of trying to give the Kingpin a check at a dinner and Fisk orders the poor guy's hand wrecked beyond repair. That's not to mention the slews of gang mooks killed simply for delivering bad news.
Donald Duck can be one mean avian. Even being the universe's Butt Monkey doesn't justify this. Once he also gave a woman a black eye because she gave him a gag gift (she didn't know it would throw a pie at him). One could even go so far as to call him Donald Dick.
Even in his 'superhero' version of some Italian stories, Paperinik the Devilish Avenger, he's quite mean. His first story as Paperinik in a nutshell: Scrooge offered him an underpaid job as a fanner and insulted him for kicking a ludicrously overpaid job as a dog-sitter that went to Gladstone, and Donald as Paperinik stole Scrooge's money-filled mattress while he slept on it and framed Gladstone for it. (The destruction of a manor that Gladstone won at a lottery wasn't part of it: Gladstone did it on his own by lighting a candle with explosive hidden in it that Paperinik left around.) While these almost murderous tendencies of Paperinik have been toned down and he now tends to reserve them for people who actually deserve the treatment, he still loves putting his quarry in Humiliation Conga, like that time he convinced Gladstone he had lost his luck due a fake curse launched on him by Donald. Donald himself is the victim of disproportionate retributions far more often than he's the instigator.
Paperinik set up a lynching mobtwice, and for rather petty offenses. The first time, it was the Beagle Boys who had decided to empty Duckburg to sack it and thus organized a marathon whose prize set him off: Paperinik's secret identity (that they didn't even know. It was just the one thing that would have convinced every single citizen but Paperinik himself to take part), only for Paperinik to detour the marathon right back in town. The second time the husbands of Duckburg, fed up with being beaten and humiliated by their wives for not measuring up to Paperinik, tried to ruin his fame as a gentleman by playing pranks dressed as him, and Paperinik reacted by having them discovered by their very pissed wives (plus Daisy. Who recognized Paperinik as Donald, guessed he was one of the pranksters and beat him up for it).
In the Doctor Who 50th Anniversary Comic Book series, "Prisoners of Time", Adam Mitchell decides to get revenge on The Doctor after he was kicked out of the TARDIS for bad behavior by teaming up with The Master, kidnapping all of The Doctor's companions and trying to force him to choose one and let the rest die.
In the Vault of Horror story "Let the Punishment Fit the Crime," a group of children end up murdering another child by pushing him into live wire. Why? He stole a girl's doll and wouldn't give it back. The local lawyer had told the kids that "robbery and kidnapping" were offenses punishable by death in the electric chair, so ...
Doctor Doom's grudge against Reed Richards of the Fantastic Four reflects this trope. In this case, however, the yearned-for retribution is really disproportionate, in that Reed didn't even do what Doom blames him for; Doom blames Reed for causing the accident which disfigured him, whereas all Reed did was bring to Doom's attention flaws in his calculations which had the potential for disaster if they weren't fixed. Doom went ahead with the experiment anyway, and when disaster happened as Reed predicted, Doom's ego couldn't let him admit fault and that Reed, in identifying Doom's error, was smarter than him. In response, he has attempted to kill Reed and his family on numerous occasions, and at one point possessed his daughter and trapped his son in Hell.
The disproportion is enhanced further in some tellings of this origin, which state that Doom was not even injured that seriously in the accident to start with. His injuries amounted to a small scar on his cheek, but Doom's vanity could not tolerate even such a minor blemish. He himself caused the horrific injuries by putting on his iconic metal face mask immediately after it had been forged without waiting for it to cool down first. So not only did Reed not cause the accident in the first place, he apparently had no connection with Doom's horrific injuries at all.
In Books of Doom, one of the tellings of said origin from Doom's perspective, Reed didn't even do that. He looked at Doom's notes and couldn't even make sense of them because Doom was blending magic and technology. He got the scar from Mephisto, the machine being designed to send him to Mephisto's realm so he could find his mother. Why he blames Reed isn't explored.
A more recent comic revealed that Reed wasn't even responsible for Doom's accident. Ben Grimm, later the Thing, didn't like Doom's attitude, and he decided to purposefully sabotage the machine. So Doom's hatred of Reed is even more disproportionate.
In the Ultimate Marvel universe, Doom has even less reason to blame Reed for his problems, as he was the one who, after being told not to, reprogrammed the coordinates for the transporter due to his egotistical belief that he knew better than the man who created the machine, transforming himself into a creature of living metal. This version of Doom... just say he has issues even beyond the Reed Richards issue.
In Frank Robinson's run on the book, he introduces the Quiet Man, who reasons for attacking the FF make Doom look justified and rational. He frames the Thing for murder, causes Johnny to lose his powers, has the city of New York kick the FF out of the Baxter Building, their children taken away and ultimately intends to frame Reed for launching a massive attack from another dimension. Why? Because back in college, the Quiet Man had a massive crush on Sue but never got the guts to tell her before Reed asked her out and thus is seeking revenge for Reed "stealing" a girl who had no idea this guy existed. Even Reed himself points out how incredibly stupid it is to launch an entire crusade over that.
Firestorm using his powers to strip Plastique naked and leaving her to be laughed at in public while he took the bombs her suit carried to be disposed of elsewhere could be seen as taking it too far. Then again, she was going to blow up lots of innocent people so you can't feel too bad for her, plus it falls under the heading of a necessary-to-save-innocents Defeat by Modesty. Or maybe in his haste he just didn't bother to take the care to remove only the bombs.
In the Lobo vs the Maskcrossover, Lobo destroys about a dozen planets in anger simply to find the guy who wrote "YOU SMELL" on his bike. (Of course, he was possessed by the Mask at the time...)
In one issue of Greyshirt: Indigo Sunset, mobster Vinnie Assapunto goes on a rampage, murdering five people because they were connected to someone who had been telling jokes about him.
Delilah Hack of Hack/Slash, who after witnessing her daughter being mistreated by a group of bullies, immediately proceeded to abduct, kill, and cook said bullies, before ultimately feeding them to their friends.
There is the mitigating factor that Johnny has to commit murder frequently to keep an Eldritch Abomination sealed away. Doesn't really make him any less crazy though.
In Judge Dredd, this is pretty much how the entire legal system works, which makes a degree of sense given how much of a Crapsack World Mega-City One is. A cover for one issue of 2000AD played it for dark laughs, showing a young kid dressed in a bad Dredd costume - presumably, dressing that way out of hero-worship - with Dredd himself barking "Impersonating a Judge. Five years in the Juve-cubes."
In Volume One, Kick-Ass leads with violence, in the face of non-violence. In particular, during his first foray into vigilantism, he brutally ambushes some young graffiti artists. Although he loses the battle, there's no indication that what he did was immoral. And this would lead to Unreliable Narrator - it's the perpetrator that's narrating the story. And the narrator is a supremely bored high schooler.
What Red Mist does to destroy Dave in Volume Two. Unmasks him, murders Katie's parents and rapes her, kills his dad, and bombs his funeral.
Mother Russia supposedly killed the other bodyguards of the Russian Prime Minister when they accused her at cheating at cards.
Laff-A-Lympics: In "The Discount of Monty Cristo", while buying a car, Dread Baron threatens to return it if the radio isn't tuned to his favorite station.
The Legendaries suffers this from the population of their native world Alysia. After they accidentally caused a magic incident by breaking a magic stone from the Arch-Enemy and accidentally turned everyone on their world into a child, the population of Alysia start hating and despising them : they are mocked, insulted, forced to hide their identities for five years, considered as failures, and everyone who has connections to them (brothers, parents, former teams...) are considered as ashamed as well. While it's understandable on the first look, it become excessively ridiculous if you take account of the fact the Legendaries also saved those same people countless times from their said Arch-Enemy (who was an homicidal, megalomaniac Sorcerous Overlordfeared in all Alysia), making the mere fact to have trapt everyone in child form not bad in comparison. The inhabitants of Alysia seems to have quickly forgotten about those heroic actions.
Early on in Lucifer, two Jin en Mok are having a discussion in a diner. When the janitor accidentally interrupts them with his sweeping, one of the Jin gives him a coin. The janitor will be compelled to look at the coin for increasing amounts of time each day with a corresponding increase of both pain and pleasure. The Jin en Mok estimates that janitor will last about a year before the coin kills him. It's implied that the Jin does this to people all the time, just because he (it) finds it funny.
In Luke Cage Noir, Luke examines a body for clues after being hired to investigate a murder. "The black and blue marks around her neck meant she was choked — which is usually personal. Though I did once choke a cellmate because he ate my peanut butter."
The very first story arc of The Mask features Stanley Ipkiss using the powers of the eponymous mask to wreak frequently lethal havoc on anyone who's slighted him in the past, making a deliberate effort to invoke this very trope. After a while, he starts to suspect that he's overdoing the entire revenge-thing.
Stanley: I mean, just because Mrs. Gazzo embarrassed me as a kid was no reason to off her.
Worst things Max and Moritz by Wilhelm Busch do: Putting gunpowder into the pipe of the teacher (OK, that's pretty harsh, but he survives.) Their punishment at the end (not by him): They're killed and ground to grit in the mill.
Enchantress wanted Dazzler dead for offending the gods by having a better singing voice than her. (Both of them auditioned for a part, and the manager, thought obviously infatuated with Amora, reluctantly admitted that Allison was slightly better.) Her first assault against Allison to tap into a dimensional rift in order to kill her rival in the middle of her performance via Rapid Aging, only to attract the attention of New York's other heroes and was defeated (and as a result, ruining what was her true plan, using the rift to gain ultimate power). She then tried to get the Asgardians to punish Dazzler, kidnapping her and dragging her to Asgard and demanded a mock duel, which she tried to turn into a real one. Fortunately, Dazzler was saved by Odin's untimely arrival; he agreed that Dazzler does have a better singing voice, ordered Enchantress to drop the matter, then sent the girl home with the promise that the Asgardians would not hurt her.
Morpheus of the Endless is also known for this: he sends a lover who refused to become his queen to suffer in hell and he didn't let her out again for ten thousand years.
When Delirium was justly pulled over by a cop (she Drives Like Crazy), she condemned him to forever think that he is covered with spiders. Lampshaded to an extent as Morpheus started to call her out on this, to which she promptly told him to mind his own business, and that with the aforementioned 10,000 years affair and all that he has little to no rights to complain at all.
In The Sentry Bob finds out that some Yoga instructor is pulling some moves on his wife; sometime later his alter egos, presumably, act; The Sentry saves 150.000 people from a crashing boat while The Void hurls a jet airliner into a building killing 150.000 people, Ramón the Yoga instructor was in that building.
Thrash the Devil in the Sonic the Hedgehog series. Your people are almost extinct thanks to horrific experiments caused by a group of Echidna scientists. You've been drilled into your head that all echidnas are evil. What do you do? Punish what's left of the echidna race that had nothing to do with those experiments by tossing all but one into an alternate dimension, possibly never returning. That one? Knuckles the Echidna.
Spider-Man is a frequent victim of this, as his opponents' goals shift from "get money/recognition/cured" to "revenge on Spider-Man" as he stops them. Justified in that nearly all of them are selfish, arrogant, unhinged bastards as foils to Spider-Man.
Venom was a particularly bad example of this: Eddie Brock hated the Spider-Man because his journalist career had been ruined when he brought forward a man claiming to be the murderous Sin-Eater, but who turned out to be a compulsive confessor instead as Spider-Man caught the real Sin-Eater.
It's even worse in some retellings, where he used his constitutional right to protect the fake, who did, in fact kill several people on his own. To reiterate, he hates Spider-Man for inadvertently getting him fired while doing the right thing when he was protecting a serial killer for his own selfish gain.
Shocker: The way I see it, kid... you owe me hundreds of thousands of dollars. Not including — not including the months I've lost in and out of the joint. Legal bills.
Spidey: Hey man, AGH!!You rob banks. What did you think was going to happen?? OW!! What did you think the outcome was going to be??
Shocker:The outcome?? The outcome is I get what is coming to me.
Spidey: You got what was coming to you. That's my point.
As it happens, the real reason is because Spider-Man made fun of him so many times, which is arguably even worse. He planned to torture a 15 year old hero to death not because he wouldn't ever stop or because he got sent to prison dozens of times, but because he was laughed at.
In Spy Boy, even Schweitzer (who is The Bully) finds a little absurd the reaction of his father to the Class president's campaign: hire a hitman to take out both Alex and his ex-girlfriend.
In the Silver Age, Lex Luthor's lifetime animosity to Superman was triggered by Superboy saving Lex from a laboratory fire. During the rescue Lex got some chemicals spilled on him that made him go bald! Later retellings of the origin have given Lex different reasons to hate Superman, usually having to do with Lex not being able to stand being inferior to him. Wanting a man dead just for being there might be one of the most disproportionate retributions on here.
In Superman: Red Son he breaks off his engagement and relationship to Lois Lane in order to devote his entire life to beating Superman because....The deformed clone of Superman beat him in Chess! This is particularly hilarious because earlier he had explicitly stated "I have no doubts that [Superman] and I would get along if we had been born in the same country."
During the time Superman was dead, Lex Luthor, in his clone body of Lex Luthor II, murdered a female training instructor because she beat him in one of their matches. Then, he gloats at Superman's grave as proof that, with Superman gone, he can do whatever he wanted to. Too bad, a little while later, she came back and tried to kill him.
The Bruce Wayne: Murderer and Bruce Wayne: Fugitive storylines? Bruce protested Lex's presidency by cancelling his defense contracts with the government. In return, Luthor arranges David Cain to frame Bruce for murder. Turns out that he chose the one guy who knew Bruce was Bats and he used it to fuck with everyone.
Bruce gets the bastard back at the end of the first Superman/Batman storyline by having Talia Al Ghul sell every last bit of Lexcorp to Wayne Enterprises.
Said assassin's main motivation for agreeing to the job and handling it the way he did? Mostly petty jealousy since his daughter Cassandra liked Bruce more than him.
In Super Crooks, the Bastard is considered the most terrifying super-villain on Earth with a story told of one guy making the mistake of trying to rip him off. Another villain might kill the guy. Another might go a step further and kill his family. The Bastard methodically tracks down and murders every single person this guy has ever been close to. Family, lovers, his drug dealer, his banker, right down to second grade classmates. Then he kills the guy.
The Adventures of Tintin: The entire reason Tintin and Rastapopoulos was put at odds with each other is because the former stopped the latter from assaulting somebody. Which lead to the latter to send people to kill the former.
In the Vampirella story "Into the Inferno" Granville decides to repay Pendragon's abandoning of his family by addicting Vampirella on cocaine.
Wanted. The main character gains the resources to do whatever he wanted. As an example, he deals with the frustration of a neighbor being too cheery with...a bullet to the face. BLAM.
Director Malcom Concord from the 2000's Weapon X series...If BUILDING A FREAKIN' CONCENTRATION CAMP for mutants, just because one scarred up your face a bit isn't disproportionate retribution, we don't know what is.
Zipi y Zape: Sometimes, Zipi and Zape are chastised for really stupid reasons, one notably one is when Mrs. Jaimita punish them to cutting grass in the garden just because they didn't know how to use a flypaper.
And Jaimita is by far the nicest one of the parents. Pantuflo, the father, borders on the Abusive Parents trope, as he's able to punish them for things they've clearly done not deliberately just as if they've done that way, and sometimes for things he's actually the one to blame.
Moose Mason in Archie Comics goes into violent rages and assaults any boy who he thinks is trying to hit on "his gurl," Midge. Interpretations of "hitting on" seeming to vary, including merely bumping into Midge by accident, accepting some item from her she didn't want (candies, etc.), or just trying to converse with her period. Earlier stories with Moose tended to be particularly brutal—one story has Moose sending Archie flying through the air just for saying "hi" to Midge. Another has him hospitalizing Reggie, when Reggie cheats him out of $5 and tries to use it to date Midge. Even Jughead (in Moose's first appearance) isn't spared from this, ending up with bandages, a cast, and a black eye (and missing several days' of school) for being asked by the school to tutor his girlfriend. Dilton's not spared Moose's wrath, either, despite Word of God claiming to be one of his "closest friends"; a 90s story sees someone try to trick Moose into thinking Dilton liked Midge, which cues Dilton flying through the air with one punch. Rule of Funny for why Moose isn't in juvenile hall/jail and has such antics tolerated by the others... I guess?!
X-Men: In Defenders #16, Magneto is fighting the Defenders and Professor X when his genetically engineered reality warper Alpha turns on him and transforms him into a baby. Years later, in X-Men #112, a rejuvenated Magneto captures the X-Men — none of whom were involved in the Defenders story in any way, but Xavier's not around — and takes a cruel "eye for an eye" revenge on them. He locks them into chairs that not only inhibit their powers but also disrupt their neurological functioning so that physically they're at the level of toddlers even though they retain adult intelligence. He then leaves them to the care of Nanny, an android with a sickeningly sweet personality to care for them as if they were babies. ("Oh Beast, you've such marvelous silky fur. You are a joy to brush. I've an idea. Would you like bows for your hair? I'll see if I can find some.") His intention is that they will live out the rest of their lives in that state, and it is implied that they are trapped that way for several days if not weeks before escaping.
Three: When Terpander makes a drunken joke about a group of Spartan soldiers who were killed in a Helot uprising, the Ephor responds by ordering his men to kill every Helot in the room.
Civil War II has Tony Stark flipping out after Rhodey's death, and kidnapping an Inhuman precog from the Inhumans. While this is bad, he did react out of grief and rage, and their response is extreme (and may be due to the fact that a normal human embarrassed them by defeating them in combat so easily): They take away his money, expose his secrets to the world, destroy anything of value to him and blow up his tower. So basically, they went and ruined his life and his company. Considering their reaction when Hellion tried to kill them all for the mists killing their people, it is interesting how they go about punishing people. Maybe Tony's actions were just more insulting.
Chaos Comics had the Villain Protagonist Evil Ernie. Physically and emotionally abused by his parents, one night Ernie sensed through his telepathic powers that his neighbors knew about his abuse for years, but were afraid to inform the police because his parents happened to own the business that was the number one employer in town, which was enough to turn Ernie into a serial killer. Now that a supernatural being named Lady Death has turned him into a superpowered zombie who can turn his victims into zombies too? He's out to wipe out the entire human race!