The basis is that since a lot of comedy is exaggeration, it includes exaggerating how people feel and react to things.
But this isn't always easy to do. If done wrong, it can seem like yelling and mugging just for the sake of it. If done right, it can make a memorable performance.
One of the distinctions of Anime, Manga, and Animesque works is showing varying silly visual ways in which characters react, from giant heads to Fireball Eyeballs. Similarly, some stand up comics work themselves into an angry state as part of the act. A Caustic Critic can also act like the Suckiness Is Painful of a work has made them apoplectic.
- This advert for www.thetrainline.com has an apocalyptic reaction to...finding out you could have got your ticket cheaper.
- A Running Gag in Fullmetal Alchemist is Edward Elric reacting to people calling him "small" both by trying to pummel them to a pulp and going into a rant about how they called him "so small that (something strange that can only be achieved by being absurdly small, like drowning from stepping on a creek)". A few times, the people try to defend themselves by saying that, no, they only said that he was "small", and that was it.
- This trope was the topic of discussion for a chapter of Sayonara, Zetsubou-Sensei, leading to the main character (and subsequently the entire class) mocking the concept of the trope by comically overreacting to ordinary everyday things of no consequence. It only lasted until Chiri got into the game.
- Futari Ecchi has Makoto overreact terribly whenever Yura says she doesn't want to have sex tonight. It's so exaggerated, he looks like he's suffering a Heroic BSoD. Every single time it happens.
- Joseph Joestar from JoJo's Bizarre Adventure Part 3, has a habit of going all out with his Gratuitous English when he exclaims. He's so loud people think he is a foreign begger who desperately wants attention and money, causing his comrades to fold in embarrassment.
- Akina of Don't Become an Otaku, Shinozaki-san! is what you get when you combine this trope with Genki Girl. Ocular Gushers and Wingding Eyes often accompany her overreactions.
- Nate from Yo-Kai Watch gets peeved when his ice cream cone only has three swirls instead of four like in the advertising photos. He insists it's a yokai's fault however Whisper disagrees, thinks he is overreacting, and insists it was a human error... It turns out it really is a yokai eating the ice cream though.
- This is the sort of thing that prompts most of the Nightmare Face moments in Junji Ito's Cat Diary Yon and Mu, which counts as Self-Deprecation as Junji Ito has made a career out of playing the former trope straight in his horror manga.
- All the time in Samurai High School. People will often be seen with a gaping mouth and shocked expression whenever something happens that is out of place or unsettling, even if it's only a little. Sometimes their eyes will even pop out when it's seriously weird. Occasionally justified, since some of the things happening are indeed very ridiculous due to it being a Gag Series.
- Lewis Black acts like he's constantly in a state of rage over everything. He says he isn't really acting nor does he prepare for any of his shows. Just give him a political topic and he'll be going for the next hour.
- Axis Powers Hetalia fanfic Gankona, Unnachgiebig, Unità: Quite a bit of dialogue is written in all caps.
- Turnabout Storm has several cases of this, from Cruise Control's loud self-chastises for commiting petty mistakes (like not saying sorry with enough remorse), to Rarity's massive rant about the post office and its lack of pens, to the point making it look like any other Berserk Button.
- The 'Help Me, Dr. Hazama!' Fanfic 'Disaster-Piece Theatre' has this little gem after Kokenoe is forced to delete all her scores in her favorite game.
Kokenoe:"GLAMOUR GIRL!!! WHY-HY-HY-HY-HHYYYYYYY!!! WHY! WHY!!! I'M SO SORRY GLAMOUR GIRL!!!!!" (flails around uncontrollably)
- A fan-comic shows Child!Feferi going out of the ocean for the first time. Despite being perfectly capable of breathing air, she clings desperately to Eridan and screams about how she's going to die.
- In Romance Points, Chiaki describes taking condoms from the nurse's office as stealing loot from a video game boss.
- In the Harry Potter series, the Dursleys are very prone to this. If anything related to magic is mentioned within fifty feet of them (such as Harry saying the phrase "the magic word", meaning "please"), Uncle Vernon will go into a yelling tirade, Aunt Petunia will scream or gasp, and Dudley will try to hide. Also, Aunt Petunia bursts into tears whenever she's proud of Dudley and let's just say he doesn't exactly have to work hard to make her proud.
- Much of the cast of Will & Grace is prone to overreacting, but Jack is the most prone.
- Quite a lot of character... heck nearly all of them... in League Of Gentlemen. If you wish to get out of Royston Vasey alive don't say the 'F' word (frog) in the Denton household, or ask if toads give you warts, call Pauline egregious or steal her pens, mention that you aren't local in the local shop and just... don't talk to Geoff (especially about your happy family life)
- This is a standard means of easy comical bits for a few incarnations of the Doctor in Doctor Who, especially the Second Doctor, the Fourth Doctor during the Romana era and the first couple of seasons of the Tenth Doctor. The Second Doctor has never had an expression he couldn't somehow do moreso, and the Fourth and Tenth are all protruding teeth and googly eyes (one short Expanded Universe story suggested that the Fourth Doctor overreacts deliberately in order to amuse Romana). The Sixth was also prone to overreacting, but in his case it wasn't funny (though it is used for humour in the Big Finish universe). In the 2015 Christmas special the Twelfth Doctor took the chance to deliver how the standard shock to seeing the inside of the TARDIS should be done in this manner, this was at a time when River Song didn't know his identity and was borrowing the TARDIS.
- One of the funniest moments of Angel addresses the Buffy/Angel romance where Cordelia and Wesley use this and imitate the pair.
- In The Eric Andre Show, Eric at one point says that hes excited for two more years of Barack Obamas presidency. Hannibal politely corrects him by pointing out that theres four years left not two (Obama had only recently been reelected), at which point the audience immediately starts booing and haranguing Hannibal as if he just said the most offensive thing imaginable. Whyre you booing me?! Im right!
- In the opening level of Duke Nukem Forever, a plan of attack is drawn up on a white board. Duke can draw or write anything they like on said board, and no matter what he puts there, a nearby soldier is absolutely blown away.
- In Pokémon Sun and Moon, Kiawe provides you with a spot-the-differences test. They begin normal enough, but start getting increasingly absurd and obvious (such as the difference being an unfamiliar man staring at the camera five inches away from it). Regardless of how easy they are, Kiawe always reacts with astonishment and disbelief that you got them right. Later appearances establish this as his defining character trait: He is calm and serious under normal circumstances but is easily impressed and awed. He also freaks out over spicy food, ironic considering he specializes in the Fire-type.
- In Streets of Rogue, the first NPC you meet in the tutorial is so impressed by your ability to do things like open doors and use lockpicks on locked doors that he literally explodes.
- In Fire Emblem Fates, Laslow and Saizo can get into a competition with each other in the Golden Path. Upon Saizo beating him by a landslide, Laslow bursts into dramatic sobs.
- Llamas with Hats is an inversion — what makes it funny is not just the destruction Carl causes, but Paul's severe under-reaction. While Paul is shocked by the things Carl does, he reacts no worse to Carl sinking a cruise ship or stabbing a man 37 times than he does to Carl making muddy hoof-prints on the clean carpet.
- Alex from DSBT InsaniT LOVES doing this, threatening to maim or kill his comrades for the most trivial of reasons.
- At one point in Gunnerkrigg Court, Kat and Annie are in the ether attempt to free a spirit from imprisonment. Due to the differences in how the two perceive the ether, Annie sees a seemingly infinite maze filled with inscrutable machinery and guarded by a fiery wraith, while Kat simply sees the spirit in a small room wearing handcuffs. When they decide to try having Kat pick the lock on the handcuffs, Annie is amazed and can't even describe what she sees when Kat simply inserts the picks into the lock, before even attempting to pick it.
- Early on, John believed his father to work as a clown for a living aId that his whole life revolved around cl— harlequins. When he found out that he was just an ordinary businessman who only filled the house with harlequin images because he believed John was interested in them, John began to have a mental breakdown...only to stop because THIS IS STUPID.
- Which was then Double Subverted when for his birthday he received one of his favorite snacks (Fruit Gushers) and found that they were made by Betty Crocker. Which then was subverted AGAIN, as it turns out Betty Crocker is led by alien mermaid Hitler. John doesn't know this, however. And he doesn't even hate Betty Crocker anymore...
- The Angry Video Game Nerd does this, but usually in the form of cuss-filled rants about how bad a game is. Also invoked, albeit positively, after discovering that Spider-Man and Venom in Maximum Carnage, a game he enjoyed, was developed by LJN.
- The Nostalgia Critic is largely based on this trope, from his reaction to the credit card gag in Batman & Robin, to practically crying over a scene in The Neverending Story III.
- The Spoony Experiment: Spoony is prone to this as well, from Screams Like a Little Girl to the cast of Wing Commander, to a rant about his career turning into in him nearly going on a shooting rampage.
- The Angry Joe Show: Angry Joe practically has this trope in his name, from an Atomic F-Bomb over the Star Wars films being redone in 3D, to fainting in joy over StarCraft II.
- When Mr. Mendo of The Agony Booth did a review of Antichrist with Diamanda Hagan, both couldn't stop screaming at the various darks forms Groin Attack that happened at the climax.
- In the Midnight Screenings of That's My Boy, Jake admits that he plays up the "Angry Jake" mood for laughs. Although the movie in question left him so actually angry, he spent the first half of the video in Tranquil Fury mode until he calmed enough to play up the angry again.
- They Made Me Watch This will get practically enraged if he sees something really stupid and/or pointless happen.
- A good portion of the humor in Two Best Friends Play is listening to the best friends overreact to whatever game they're playing, Pat in particular has a very short fuse when it comes to Matt's stupidity. Turned Up to Eleven in the Heavy Rain episode where they spend most of the video shouting excitedly as Ethan does mundane activities like drinking orange juice and playing with his kids.
Pat: YEAH KIDS YOU READY FOR THESE 24 INCH PYTHONS?!
Matt: AHHHHH SUPER SAIYAN LEVEL 3!
- The real (only) reason that people tuned into True Capitalist was to listen to Ghost go absolutely batshit insane from all the troll callers.
- Ethan from H3h3productions is occasionally "triggered" by idiotic videos which causes him to seize hilariously in his chair.
- AlChestBreach is known to do this, his emotions ranging from Heroic BSoD to finding random things, like traffic cones, supremely interesting. In reference to seeing a random traffic cone: GASP
- ProtonJon of The Runaway Guys lapsed into this a few times during their LP of Mario Party. The highlight of these was a long chain of screaming "GAAAAAAAAAAAAAAAAAAAME!!" whenever something didn't go his way. See it here.
- Chuggaaconroy, another one of The Runaway Guys, basically has this as one of his big shticks. Whenever something goes wrong or generally surprises him, Chugga tends to start shouting.
- Let's Player azuritereaction enjoys going on huge, exaggerated rages in his videos when he's losing a video game.
- In the Ultra Fast Pony episode "Bummer In The City", when someone says "Have a nice day" to Rarity, she responds with "How dare you tell me how to live my life?!"
- One of Phineas and Ferb's devices accidentally split Candace into two selves representing her two biggest obsessions: being in love with Jeremy, and needing to bust her brothers. Busting Candace was so shocked by the sight of Lovey-Dovey Candace leaving the mall with their mom Linda that she screamed and pointed in a Shout-Out to Invasion of the Body Snatchers (1978).
- SpongeBob SquarePants does this a lot.
SpongeBob: Squidward! WE'RE OUT OF NAPKINS! OH, OUT OF NAPKINS!
- In "The Algae's Always Greener", this is his reaction to getting a customer the wrong-sized drink.
Spongebob: I've soiled the Krusty Krab name! Soiled it! Soiled it! Soiled it!
- Patchy the Pirate does this in "The Sponge Who Could Fly", where he reacts to the lost episode of SpongeBob SquarePants being a clip of walk cycles by angrily knocking over all of his SpongeBob merchandise and declaring that he will run away. As soon as the real lost episode starts playing and his parrot Potty informs him that there's more, the scene of Patchy's tantrum is humorously played in reverse.
- In "The Algae's Always Greener", this is his reaction to getting a customer the wrong-sized drink.
- The whole shtick of the "Katie Kaboom" shorts on Animaniacs is that Katie hulks out and becomes a rampaging monster over something trivial. "I am not overreacting! I'M A TEENAGER!"
- Minerva Mink as well, this time mainly other characters reacting to Minerva's beauty.
- The Simpsons: In "The Boy Who Knew Too Much," the following exchange occurs in open court:
Defense Attorney: ...and, therefore, you would never lose your temper over something as trivial as the pronunciation of "chowder"?
Freddie Quimby: That's chowDUH! ChowDUH! I'll kill you! I'll kill all of you! Especially those of you in the jury!
- My Little Pony: Friendship Is Magic:
- Comical overreacting to little things is Rarity's stock in trade. Generally, just the little things, though. In "Lesson Zero", she loses a spool of ribbon she needs for her latest fashion project, and declares it "The! Worst! Possible! THING!"; she later in the episode says the same thing about forgetting to bring the plates to a picnic.
- However, Rarity is by no means the only one to do this. All of the Mane Cast have done this at least once, and Twilight Sparkle once spent an entire episode basically coming unhinged because there was no problem.
- On Futurama, the episode S04E05 has Bender audition for a role on "All My Circuits", only to pronounce Spanish words as phonetic English (e.g. Chihuahua as "chee-hue-hueh"). Calculon responds by punching the desk and declaring it was so terrible it probably gave him cancer.
- In the Gravity Falls episode "Blendin's Game", Mabel's reaction to a piece of candy getting stuck in a vending machine is to cry out "Everything is terrible forever!"
- In the American Dad! episode "Every Which Way But Lose", Stan tries to hang himself because his peewee football team lost a game. Later, at a carnival, Steve tries to teach Stan that everyone loses some time by having him play a carnival game (which is, of course, rigged); when he fails, Stan immediately puts a knife to his own throat.
- Star vs. the Forces of Evil: In "Gift of the Card", Marco has to use a Quest Buy gift card that Star gave him before it expires and kills him. He decides to buy a security wallet in plum, which he claims is his favorite color, but the clerk informs him the only wallet they have is in Prussian blue. As it turns out, that's Marco's real favorite color, and this revelation causes Marco to burst into tears of joy.
- Kaeloo: Mr. Cat's reaction to losing a whisker:
Mr. Cat: AAAAAH! OH NO! I'M DEFORMED!
- Stumpy's reaction to anything not worth being scared, worried or shocked about. If there is something he should be reacting to, he calmly ignores it.
- Steven Universe: Pearl is particularily prone to this, best shown in the Crossover with Uncle Grandpa, when the Crystal Gems get stuck in a white void.
Pearl: "We will never escape! This is our new home!"Garnet: "Pearl, you're overreacting"Pearl: "I'M NOT OVERREACTING!"