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 literally 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 one hell of Humiliation Conga, like that time he convinced Gladstone he had lost his luck due a fake curse launched on him by Donald.
It's worth noticing that Donald himself is the victim of disproportionate retributions far more often than he's the instigator.
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.
In the JLA storyline, "Tower of Babel", Ra's al-Ghul decides to end all of humanity by scrambling human speech all because one of his servants killed a rare tiger by feeding it chocolate.
Double subverted in the Simpsons comic "The Cask Of Amontillad'oh", which references the "Cask of Amontillado". Moe, having been fed up with Homer not paying for his beer, apparently decides to trap Homer behind a brick wall where he'll die from thirst and starvation along with a lack of oxygen. However, it's then revealed that Moe was simply trying to scare Homer into giving him the money. The double subversion occurs when Homer reminds Moe that he also insulted his pickled eggs, to which Moe responds by cutting up Homer with a saw blade.
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.
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. Of course, this version of Doom... let's just say he has issues even beyond the Reed Richards issue.
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.
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 one issue, Johnny couldn't get his world's equivalent of a Slurpy in the middle of the night (they turned off the machines), and he felt the appropriate response was to throw a scary tantrum, murder the cashier with his own gun, and then (turn it on himself). But we kindaknowthe protagonist by now -- you don't really need to highlight the spoiler to guess what happened.
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.
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.
Also a subversion in that the Shocker's real reason for wanting revenge of Spidey so badly is that Spidey mocked him every time they clashed -- and he felt the whole world was laughing at him -- and he finally snapped. Finding out Spider-Man was just a kid didn't help his mood. The entire chapter was meant to show the Shocker was an Ineffectual Sympathetic Villain -- with the emphasis on "Sympathetic" and the "Ineffectual" de-emphasized.
After Peter got himself free and beat Shocker up again, the story ends with the cops coming to arrest him and one commenting about Shocker being just a living joke.
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.
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.
Wanted. The main character gains the resources to do pretty much whatever the hell he wanted. As an example, he deals with the frustration of a neighbor being too cheery with...a bullet to the face. BLAM.
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."
Enchantress tried to get the Asgardians to punish Dazzler for offending the gods by having a better singing voice than her. Fortunately, Odin 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.
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.
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.
In Luke Cage, Hero for Hire 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 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 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 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 ...
Worst things Max Und 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 grinded to grit in the mill.
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. Of course, the inhabitants of Alysia seems to have quickly forgotten about those heroic actions.