The first battle of Arkansas Post in 1824: The Arkansas War by Eric Flint. 1200 undisciplined freebooters face 1200 trained soldiers with a sturdily built fortress as their base of operations.
In Animorphs, Erek King, the millennia-old robot that is capable of generating personal forcefields and shrugging off being hit by a truck. He can move faster than the eye can follow and is described as being able to "obliterate you down to your individual molecules"; however, he's hardwired to hate violence and can never commit any violent act. In one instance, this is subverted, allowing him to rescue the Animorphs. The fight lasted less than a minute, and was only vaguely described. In the time it took you to read this paragraph Erek managed to kill dozens of Hork-Bajir. Afterwards, Erek begged to have his original protocols restored. Rachel saw it and the brutality reduced her to tears.
The final showdown in Therin Knite'sEchoes (the first book), where (a furious Adem uses his echo-maker powers to hunt down a terrified, fleeing Brennian, shoot him in the chest, and then push him off the edge of the dream with a butterfly—that Adem created earlier by destroying Brennian's own dream dragon.)
A novel in the Coruscant Nights trilogy has Captain Typho, Padmé's old bodyguard, try to avenge her death at the hands of the newly-minted Darth Vader. It's really obvious who wins, but earlier in the novel Typho did beat the Force-Sensitive bounty hunter Aurra Sing, and he'd bought part of the carcass of an animal that blocked Force abilities, and he'd lured Vader into coming alone and not having any (physical) weapons. Still, he gets destroyed, and fast. Should have gone with a live ysalamiri, Captain. He does manage to really shake up the Dark Lord by having his last words be an accusation about killing Padmé.
In Death Star, there is a point where five hundred X-wings show up to attack the almost-finished first Death Star. They don't have the plans and neither Luke nor Biggs nor Wedge are with them, but still, five hundred X-wings. All of them die; the superlaser's very first test firing is on their carrier, they can't make a dent, and the battle station's TIE pilots eliminate all of them. Considering that at Yavin the Rebellion has thirty X-wings at most...
One of the qualms some fans had about the New Jedi Order series was that the first dozen books or so are about the good guys losing over and over (and over and over and over) again. This is something of an unwarranted reputation, with the first few books featuring a lot more back-and-forth with the Vong's vanguards and smaller-scale antics with spies and so forth. Then there's Ithor (everybody loses, but the Republic loses more), Fondor (pretty much the same, thanks to misuse of a superweapon taking out three quarters of the Republic fleet) and a list of one-shot planets getting conquered, but the most shocking and significant defeat is the loss of Coruscant in Star by Star. Contrast the Enemy Lines duology, where the Vong have the misfortune of running into General Wedge Antilles and suffer not one, but two costly and embarrassing defeats.
Almost any battle Thrawn's involved in, no matter his resources, will be this, most prominently when he's in his prime as Grand Admiral in The Thrawn Trilogy. He only dies when his Noghri bodyguard kills him, and one of the few battles he was present in that he could be said to have miscalculated was also because it was very first encounter with a Jedi Master—a very mad Jedi Master.
Even in-universe many assume this about Thrawn even when they don't know the circumstances. In the Hand of Thrawn duology, a character describes Thrawn's first encounter with ships from the Republic, when he was massively outgunned and completely unfamiliar with the enemy technology. Mara Jade simply asks how badly Thrawn beat them. (The answer is this trope. We get to see it happen in Outbound Flight.)
The Star Wars Radio Dramas supply the Battle of Derra IV, in which a Rebel supply convoy bound for Hoth and most of the X-wings escorting it are slaughtered in an ambush by a TIE wing. In later materials the ambush was planned by Thrawn, though he didn't personally take part.
In Shatterpoint, Jedi Master (and General) Mace Windu takes a fleeing army regiment and a tattered, almost-defeated band of partisans facing off against a heavily-armed enemy with tons of reserves and total aerial superiority and not only wins, but wins with such elegance and efficiency that the narration outright says that it would have gone down in the history books as one of the master strokes of his career were it not for his sociopathic ally Kar Vastor. For instance, one of his units uses stealth, misdirection, and elite assault troops to capture the enemy's sole spaceport without taking a single casualty.
Executive Orders features the operational strategy that proper warfare is taking organised and technically advanced armed forces and arranging them skillfully with the express purpose of Curbstomping. The UIR tank corps gets this treatment rather forcefully toward the end of the book.
The battle in Brazil from Rainbow Six: 30 ecoterrorists against 15 Rainbow troopers. Only about 4 of the ecos make it to safety. It's so one-sided that Clark and Ding, hardened special forces men and former intelligence officers who're no strangers to playing the Anti-Hero, find it pure murder. Justified with the first three counter-terrorist missions. Once the Badass Crew gets into action, they take down all the Tangos without losing a man - but before beginning the operation, we are shown how they need to gather information and plan out the execution. The men also train over and over ad nauseum in preparation for taking a mission. Using flashbangs to disorientate the targets before going in doesn't hurt.
Also, the last 300 pages of The Bear and The Dragon are almost 100% Americans blowing up whole Chinese armies in scene after scene, battle after battle. Well, occasionally they let the Russians have some fun too. Other than a brief subplot with a nuclear missile, the outcome is never even close to contested once enough supplies are delivered for NATO (Russia becomes a member in the novel) troops.
In Debt of Honor, much is made of the fact that the US doesn't have the resources to properly confront Japan in armed conflict, which is actually what spurs the Japanese to their crazed attempts at imperialism. The US forces then proceed to demonstrate that their winnowing of their combat inventory has not made them any less effective. Japan protects their islands from bombing with an "impenetrable" air defense network focused on AWACS aircraft that can't be approached by anything in the air, as they can even detect stealth fighters. So they're crashed by CIA operatives on the ground and then spoofed by clever (and dangerous) fighter tactics, both of which the Japanese did not expect. The Japanese respond by bringing their surface ships into a patrol pattern around their islands to provide radar coverage almost as good as the AWACS, and the US responds by using their ballistic missile submarines, previously about to be decommissioned, as attack submarines to savage the surface ships. The Japanese finally try to hold the Marianas islands with their formidable air force, only to have it utterly destroyed by a US Navy planes and cruise missiles. The end result is the devastation of the Japanese forces, with only 2 dozen US aircraft lost.
The series is inordinately fond of this trope, especially with regards to resident badasses Quick Ben and Karsa Orlong. It tends to lead to many anticlimaxes, when battles are foreshadowed for most of a book, then are finished within a couple of pages.
This is pretty much how the island nation of Malaz ended up becoming an empire. Its ruler recruited very powerful mages, highly skilled assassins, traded for large quantities of powerful explosives and gained the allegiance of an army of unstoppable undead. With these resources he trained an elite army and proceeded to curbstomp all the neighbouring nations.
In the series you know that things are really bad when a Badass Army which has been doing the curbstomping for a couple books already, itself gets curbstomped simply because they were in the way.
Percy, Frank, and Hazel against the First and Second cohorts in the war games.
Also, Hazel and Frank against Alcyoneus the giant. It wasn't a totally one-sided battle, but they really gave him a beatdown.
Gaea and the giants as the ultimate threat to the Olympian Gods for four books. Throughout the books individual giants are defeated relatively easily despite being specifically designed to battle reality warpers. In book five, The seven demigods are able to hold off all the giants at once and only start to lose thanks to the giants only able to be killed by a god and demigod working together. Once the gods show up, it turns into a Curb-Stomp Battle since the giants cannot match the gods's powers. Worse, Gaea is awakened and supposed to be a immortal threat the combined gods cannot handle. A few demigods, some charmspeak and a minor explosion later and Gaea is supposed to be gone forever.
The Battle of Saltash in Shadow of Freedom when five RMN destroyers defeat four Solarian battle cruisers.
Several battles, mainly because the Manticorans have the best tech in known space. One incident involved the Manticoran admiral, with a small task force, demanding the surrender of her opponent, the admiral of a large fleet that outnumbered her several - to - one, and also had (or so they thought) the best technology and training in known space. When the demand is refused, the Manticoran admiral effortlessly blows away the enemy flagship, and then declares her intent to blow up the entire chain of command until she finds someone reasonable. When you have the capacity for one of your pod battlecruisers to Macross Missile Massacre pretty much any five enemy ships, this is the case except with massive outnumbering. Even when she didn't have podbattlecruisers, just 8 Nike class battlecruisers 8 Edward Saganami -C cruisers and some tincans, versus the 20 battle cruisers of the Solarians.
Another Manticore Missile Massacre in Mission of Honor: 71 Solarian superdreadnoughts versus a handful of Manticoran heavy cruisers with — the crucial point — a crapload of Apollo pods. The Solarians surrender after one salvo kills or cripples a third of their fleet, from far outside their own range. Also, may apply to Operation Oyster Bay, which curb stomped Manticore and Grayson's orbital industry. There'll be fewer Manticore Missile Massacres without the factories to make the missiles...
Though this may no longer apply since Beowulf, which is entirely intact, is now manufacturing the missiles that Manticore can't, and Havenites are now firmly on the side of Manticore with their large Bolthole shipyard (which Oyster Bay was originally supposed to destroy as well, but that part of the mission was scrapped) manufacturing the ships to use those missiles.
Another example is found in At All Costs when the Apollo missile is first introduced, and Honor's outnumbered fleet effortlessly trashes three Havenite fleets before reducing the entire orbital infrastructure of Lovat to rubble.
On a more personal level, Honor Harrington vs highly experienced duelist who is hired to essentially murder people legally. He doesn't even get his arm pointed in the right direction before she drills him. With a nonlethal shot. Intentionally. From the hip. And keeps firing, hitting him higher and higher up the body in a matter of seconds before she puts the last one between his eyes.
Lampshaded in Honor Among Enemies when strings are pulled behind the scenes to deal with a violent crewmember by training one of his victims. At the end the bully's greatest annoyance is not at losing a fight, but rather at never having managed to land a single blow.
The worst curb-stomp in the series (thus far) was the Second Battle of Manticore: a massive invading Solarian fleet versus the combined forces of Manticore, Haven, and Grayson. With roughly equal numbers of ships (but several generations of technical advance on the part of the Grand Fleet), the end result? A few small vessels destroyed and 11 ships slightly damaged on the part of the Alliance, with about 2000 personnel killed in action. The Solarians have 296 superdreadnoughts totally destroyed, almost all the rest of them damaged, 1.2 million crew killed in action and 1.4 million taken prisoner. Only the opening salvos and the aftermath are described; the actual battle is so one-sided that the narrative skips it.
To date any time The Sollies go up against the Manties the result is minimal, if any, casualties for the Manticorans, and a slaughter for the Solarians.
An example early in the series (The Short Victorious War) was a complete fluke. The Havenites launch their first real attacks on Manticore. One of the battlecruiser squadrons involved has the misfortune to encounter the dreadnought HMS Bellerophon rotating home, which flattens them with little effort. Bear in mind, this battle takes place before most of the uber-tech shows up: Bellerophon was a normal DN, not a podnaught, and Honor was in another star system entirely. However, even then, it was virtually impossible for even four battlecruisers to go up against a dreadnought and win, even though there was only a junior officer with no combat experience in command of it at the time. Interestingly, it was his inexperience that contributed to the sound defeat of the Havenite ships, as he ends up giving the exact right orders that win the fight but without the hesitation an experienced combat officer might have employed. This ends up having long-reaching consequences for Manticore, though, as Rob S. Pierre's son was on one of those battlecruisers. His death is the primary reason he leads his coup of the Legislaturalist government and establishes the tyrannical Committee of Public Safety.
Considering how often technology changes, and how fleet admirals do their best to outnumber the enemy when they attack, most battles in the series are a curb stomp by one side or the other. (Realistic, since commanders will generally not go looking for a fight that they don't already know they can win.)
The Battle of Cerberus is the first time Honor beats a superior enemy force with absolutely no casualties on her side. No tech differences this time, since both sides are using standard Havenite tech. Honor manages to predict where the enemy fleet will show up, then manages to maneuver her ships without her impellers (using reaction thrusters only), making the ships virtually invisible to the standard gravitic detectors (nobody bothers to look at other sensors), to within energy weapons' range and hit the unsuspecting enemy up their vulnerable sterns. A few enemy ships manage to get off some missiles, but those are easily swatted aside by Honor's counter-missile systems. However, in the following novel, Mike Henke gets into an extended analysis of the battle and points out everything that could have possibly gone wrong and resulted in Honor herself getting Curb Stomp Battled.
The opening sea fight of the war in The Great Pacific War is this, and everybody knows it even before it happens. Modern Japanese dreadnoughts with long-range firepower are going against the smaller and mostly outdated vessels of the US Asiatic Fleet. The US Admiral's pre-battle plan is entirely based on how to lose in the least bad way possible.
In Space Marine Battles, most of Mortarion's fights against Grey Knights end up this way, mostly because they are "simply" Super Soldiers, while he's a Super Prototype super-Space Marine turned daemon prince and pumped up on Warp, not to mention that he has almost ten thousand years' worth of combat experience.
Villains can sometimes be killed by accident or after a really long fight scene. Villains that are experienced fighters (Ungatt Trunn, Cluny the Scourge, Feragho the Assassin) can put up a real fight and sometimes even kill the protagonist, causing their opponent to invoke Taking You with Me. Other creatures that are reputed to be great fighters (arguably the most humiliating example is Princess Kurda in Triss, though Ironbeak in Mattimeo also gets his ass royally thrashed) will normally be killed either by accident or when their skills are actually called upon to be tested. And some, like Gabool the Wild, Slagar the Cruel and Mokkan, die by an accident or because they're not in a position to fight back.
Bluddbeak the eagle takes on three adders, despite being blind, old as dirt, and rheumatic. Ah, what's the point of a spoiler tag? He loses.
Happens several times in the Axis of Time trilogy. It's to be expected however, considering that the basis for the trilogy involves mismatching World War II technology against a military force from 2021... The World War II admirals are shocked at how calm and methodical the "uptimers" are, as an "uptime" Australian submarine is obliterating a large chunk of the Japanese navy from miles away. No battle fervor, no regard for the thousands of lives they've just extinguished (video gamers are more excited about destroying the enemy). They wonder what sort of a world the "uptimers" have come from that made them take mass murder so dispassionately. Part of that has to do with the War on Terror that has been dragging on for 20 years in the 21st century. Part of that is because, to the "uptimers" the people they're killing are already long-dead in their past.
A small Virginia mining town from the year 2000 goes back in time to 1631 Europe — has several such battles, initially as the Americans unleash modern weaponry against that available in Europe. However, this gets gradually averted as the series progresses.
Admiral John Chandler Simpson's new ironclad warships vs. the battery defenses of Hamburg. Said defenses wind up as hamburger.
Muggles generally don't stand much of a chance against channelers, who just have too damn many awesome powers, but the Asha'man in particular really rub this in, as they undergo Training from Hell for the express purpose of becoming living weapons. When they show up, people tend to explode. Messily. For their first battle, they teleport into the middle of an enemy camp and proceed to turn the surrounding army of elite desert warriors into chunks of gore while they chill behind their force fields.
Then there was the time Rand balefire-nuked Graendal's mansion... we find out in the following book that she escaped, but wow.
In John C. Wright's War of the Dreaming second book, two of these happen within a short span: Acheron's advance guard vs the US Pacific Carrier group, where the round goes to the humans and Morningstar vs the fighter jet air strike group. Unusual in the instance that it's The Cavalry that gets stomped.
Specific examples aside, this is a running theme of The Dresden Files, as a noir story in something of a Crapsack World, there isn't really a single Sorting Algorithm Of Power so much as every power bringing with it a cost and a weakness. Most novels start with Harry not yet knowing the weak point, putting on the receiving end of the curb-stomp, and end with him finding it and applying the appropriate lever, putting him on the giving end. There is very little middle ground in magical combat.
In Storm Front when Harry goes to Marcone's club and confronts Gimpy Lawrence a traitorous gangster. He tries to shot Harry, but Harry blocks the bullets with magic and Gimpy is shot dead by Marcone's bodyguard Hendriks.
The fallen angel Magog tries to take on Eldest Brother Gruff. Magog gets annihilated in a single shot, without Eldest Brother Gruff even really trying. Dresden likens it to Gruff swatting him like "an uppity pixie."
Michael in vs several hundred hobs (evil Winter fae), some of which are armoured and some the size of Mountain Gorillas. Michael barely breaks a sweat. Of course, wielding freaking Excalibur helps.
In Turn Coat, the Skinwalker utterly thrashes Harry, Luccio, Lara and several other White Court vampires, and a half dozen human gunmen. That same being had earlier reduced Harry to near-gibbering uselessness just after seeing it.
In Cold Days, Harry, now the Winter Knight, fights Fix, the Summer Knight. Fix has about ten more years of experience with the job, and has been preparing to fight the Winter Knight nearly that entire time. Furthermore, Fix is at full strength, and has his magic armour and sword, while Harry is running on fumes and has been stripped naked. But Harry has a few things going for him that Fix can't counter. First, Harry is still one of the world's most powerful Wizards. Second, Harry has enough willpower to ignore the combat sense the Winter Knight Mantle bestows him, which Fix would know how to counter. Third, the fight takes place on Demonreach, which grants Harry total knowledge of everything on it. Some conjured mist robs Fix of his sight, leaving Harry unhindered. Harry takes Fix down so easily he feels almost ashamed, saying he feels like he's fighting a blind man.
The first book of the series pits the island kingdom of Charis against every other naval power in the world. Contrary to what everyone in the book expected, the fact that Charis's was the only proper Navy combined with the technological innovations provided by Merlin Athrawes allowed Charis to decimate its foes so completely that two books later they're still racing to recover.
And have just realised that the massive galley fleet they're building will be useless against Charis' galleons.
"Oh, they'll be a huge improvement over the old ships. Unfortunately I'm coming to suspect that that means it will take one of Cayleb's galleons three broadsides to sink them instead of just one."
A Mighty Fortress, the fourth book, has the Church finally recovering from their past failures and getting ready to launch the Navy of God. Despite some successful misdirection, the Charisian leadership find out about this, and manage to get a force in place to intercept. The Navy of God had nearly 140 ships (though not all of them were fully armed yet), the Charisian force had about a fourth of that. Thanks to the Charisians attacking in the black of night and making the first ever use of signal rockets and exploding shells, Seven of the Navy of God's ships return to safe harbor. The rest are either destroyed or captured. The Charisian cost is higher than the first time around, but was still an overwhelming victory.
Both Wizarding Wars went mostly this way with the bad guys delivering. It is implied that in the second one they didn't suffer even a single man dead or captive. Until the Final Battle, where the good wizards kicked the ass of the Death Eaters.
In Harry Potter and the Order of the Phoenix Dumbledore vs. roughly ten Death Eaters. He successfully manages to stun them and bind them to the room. The only one who escapes is Bellatrix Lestrange and even she gets incapacitated shortly after.
Earlier on he quickly defeats Fudge, Umbridge, and legendary aurors Kingsley and Dawlish in a few quick seconds and leaves them unconscious. Granted, Kingsley was on his side secretly, but they still had to make the fight look good.
Hagrid vs. about five or six aurors. Things don't go well for the aurors especially after they nearly kill McGonagall and Fang.
Harry vs. Bellatrix. Bellatrix completely mops the floor with Harry. Granted, he did manage to hit her once, but it did little more than entertain her.
Ender's fight with Bonzo probably counts. Bonzo was older, bigger, stronger, and intent on Ender's blood and the fight was set up for several chapters. But when it finally happened, Ender defeated Bonzo in three strokes, finishing with a Groin Attack. It's later revealed that Ender killed Bonzo in the fight, and suggested that Bonzo was already dead when the last kick landed.
Note that curbstomping is central to Ender's strategy. As he explains it, he really hates fighting, so when he has to fight for real, he prefers to win so thoroughly that he preemptively wins every other fight he would have had. Bonzo wasn't the first bully to be on the receiving end of this philosophy. And yes, Ender unknowingly killed that one too.
As one of his superiors says to concerns that Ender might be too sociopathic to be useful, " Ender Wiggin isn't a killer. He just wins - thoroughly."
The first prequel novel Earth Unaware has this with El Cavador, which is destroyed by a single shot from the Formic/Bugger ship. The only survivors are women and children and Victor, who aren't on the ship at the time.
The second prequel novel Earth Afire has this continue with almost any force that faces the Formic ship. The kicker? This is just an advanced scout, not even a proper warship. The Formics don't start building warships until they find out about the destruction of the scout, since their motherships are mobile factories. When those arrive, the International Fleet turns out to be just as useless (described as shotguns firing at balloons) until Mazer Rackham makes his move. To be fair, they already have "glasers" (gravity lasers) at this point, which are the precursors to the Little Doctor. However, Formic shields are pretty good about countering glaser shots, requiring IF ships needing to close to "knight fight" distance to do serious damage, while Formic gamma plasma guns have a much longer range (and humans don't have shields).
In Mikhail Akhmanov's novel Invasion, humanity's finest get their asses handed to them by a massive alien starship. The so-called Battle at Martian Orbit is decidedly one-sided. The alien ship is surrounded by a dozen Earth cruisers, armed with nukes, swarms (a Magnetic Weapon that fires a fast-moving icicle spread), and scores of fighters. The alien ship launches "combat modules" armed with Antimatter weapons that make short work of the fighters and the cruisers in a matter of minutes, while losing only several of these modules in the process. Before going out in a blaze of glory, the cruisers manage to launch a Macross Missile Massacre nuclear barrage at the starship with a combined force of 400 gigaton. The alien ship's Deflector Shields easily absorb the destructive energy without the crew even feeling it. The aliens then send a video-recording of the battle to world leaders as a demonstration of their power.
Two more examples take place in the fourth novel of the series, Dark Skies, about 250 years after the events of the first novel. The Earth Federation sends a battlegroup to liberate three human colonies from a race known as the Dromi (a cross between Lizard Folk and Fish People), believing the occupational forces to be minimal. The battlegroup finds an entire Dromi clan facing them and is promptly obliterated by the sheer numbers, despite having superior weaponry (the antimatter weapons reverse-engineered from the aliens in Invasion). The second example occurs at the end of the novel when an entire fleet of a new type of heavy cruiser (with twice the firepower of the previous design) arrives and blasts the Dromi away. In fact, the Earth Fleet is pretty good about destroying the much smaller and weaker Dromi ships (their so-called "dreadnoughts" are about the size of human frigates, which are dwarfed by human cruisers), but the Dromi have HUGE numbers (as in, their population outnumbers all other known races put together several times over), they breed like crazy (putting rabbits to shame), don't fear death, and are perfectly fine with utilizing Zerg Rush tactics. In fact, humans win many individual battles, but the sheer number of the Dromi results in the war dragging on for over a century.
In Mistborn: The Final EmpireKelsier's final battle against the Lord Ruler is pretty much this. It's immediately after one of the single most awesome fight scenes in the book, wherein Kell kills an Inquisitor, making it all the more shocking when the Lord Ruler basically just backhands his face off without breaking stride.
At the end of that same book, Vin and Marsh take on the Lord Ruler. Keep in mind that this is a Mistborn and an Inquisitor, two of the most powerful beings in the setting. The whole fight is basically the Lord Ruler shrugging off everything they can hit him with while casually tossing both of them around his throne room. And then Vin realizes what his Achilles' Heel is...
One of these is deliberately engineered by Vin in the final book. She takes on thirteen Steel Inquisitors at once to try to put herself in enough danger to trigger an 11th Hour Superpower. Turns out she got the mechanism wrong, but it worked out anyway - halfway through, the fight turns from the Inquisitors breaking every bone in Vin's body to Vin smashing a castle on top of them.
Also from Mistborn, in The Alloy of Law, the fight at the wedding dinner where Wax and Wayne kill or drive away forty Mooks, although they did get away with one of the hostages they wanted.
To emphasise this, they accomplished this when the Mooks were all armed with guns, in a room packed with civilians, with no fatalities on the side of the civilians (except one who was killed before they intervened).
World War III from the Keepers series (or pretty much every battle from WWIII in this series). The Germany-based Apex Empire takes over the world in a year. The Allies were completely outwitted (even for the decade prior to the short war, which was when Germany created its new empire) throughout. For starters, the entire population of the Allies had to be evacuated to North America just so they wouldn't be slaughtered (militarily) right from the outset. Even before the war became global, Germania (Germany plus Austria and the Czech Republic), along with Israel, essentially conquered the Middle East in three days (one of which was spent utterly defeating the combined invasion force of the Middle East against Israel), while killing almost no enemy combatants. The Apex Empire eventually deploys a superweapon that can only be described as an animalistic, small-mountain sized moving fortress/SHOOPDAWHOOP canon/Dakka worship doomsday weapon. To put things into perspective: the Allies, right before the war, designed a moving fortress that was supposed to be huge, like a superweapon. Well, each of the legs of the Juggernaught (the Apex's superweapon) is the size of the Allies' moving-fortress. And it had dozens of legs. Essentially the Real Life version of Flawless Victory, in the form of a WORLD WAR.
In Pocket in the Sea the seemingly final battle kills all of the enemy, with token loses for the heroes. This trope is subverted, slightly, in that the heroes have no idea how thoroughly they've trashed the enemy, until they go and see for themselves.
In The Silmarillion, the Battle of the Sudden Flame is probaly the greatest curb stomp in the book. The fortress of Angband is surrounded by the combined armies of the high elf lords of the Noldor and friendly tribes of men. Melkor, the original bad guy of Middle Earth and Sauron's master, starts off by covering the fields where the elves are with fire, then lets loose an army he's been spending years building. Led by the Glaurung, the father of all dragons, an awesome tide of orcs spews forth to crush the armies of the elves. The elves are so crushed by this battle that they never regain the momentum. Kingdom after kingdom falls to the hand of Melkor. The only way to save Middle Earth is to get the gods come and save them.
The Battle of Unnumbered Tears was even worse. It started as a noble effort of the Elves, Men, and Dwarves to defeat Melkor forever and was the greatest host ever seen outside that of the gods. They were defeated so horribly and so many people died that Melkor literally made a mountain of their corpses. That was the point that everyone realized they could not win the war.
But when the Valar finally respond to Earendil's embassy, they come in mob-handed, personally heading up an army of all the Elves in the Undying Lands who were willing to sign up, head for Thangorodrim in basically a straight line, shrug off all attempts by Orcs and Trolls and Balrogs and even freakin' Dragons to so much as slow them down, whereupon Tulkas personally makes Morgoth his bitch and the Valar throw him out of the cosmic door into the Outer Darkness. The collateral damage is immense, though.
In David Weber's Out of the Dark, humanity gets curbstomped when the alien invaders launch a pre-emptive strike that kills roughly half the population on Earth, destroys most of the planet's cities and military infrastructure. However the human guerrillas that refuse to surrender curbstomp the aliens' ground forces repeatedly as they're unused to an enemy that won't quit once their cities have been flattened from orbit. Up until the aliens discover chemical warfare. Unfortunately, they then piss off Dracula. Deciding to be the good guy, he and perhaps a dozen or so vampires he creates (all dedicated resistance fighters) effortlessly obliterate the entire invasion force, and steal their ships. The epilogue of the novel is dated as "Year One of the Human Empire" as Dracula and some of his people are taking their captured warships to visit destruction on their invaders and, it is implied, express humanity's extreme displeasure at the other galactic species who allowed this to happen.
One of these is mentioned in the prologue of James Blish's The Quincunx of Time. A vast enemy force attacked, "a massed armada that must have taken more than a century of effort on the part of a whole star-cluster ... under the strictest and most fanatical kind of secrecy." And the Service was waiting for them with three times as many ships, all positioned so perfectly that any attempt by the armada to fight would've been plain suicide. "The attack had been smashed before the average citizen could ever even begin to figure out what the attackers might have thought it had been aimed at."
In the short story A road not taken, faster-than-light and anti-gravity drives are very simple machines, ones that every race in the known universe has discovered in their respective Ages of Sail. Every race but humankind, that is; for a bizarre twist of fate, we missed it. As a result, while humankind devoted itself to advanced science, every other race concentrated all their efforts into traveling the stars, ignoring science for the sake of intergalactic conquest carried out with primitive spaceships, arquebuses, bayonets and Napoleonic tactics. So one day the Roxolani come across planet Earth, decide to conquer it, and are faced with the unexpected problem of fighting an enemy so stupefied by their backwardness that they actually worry whether it's fair to even shoot at the Roxolani at all. When they decide that it is after all, things go...badly for the aliens.
In the sequel Herbig Haro it's the humans' turn to be on the receiving end as they find a species which has also not developed the drive, and thus hasn't been sidetracked the way the humans allowed themselves to be.
In the Worldwar series, the alien Race delivers one of these to about half the planet within the first week or so of their invasion. South America, Africa, Oceania and large parts of Asia fall to them extremely quickly. Although North America, Europe and parts of Asia do a better job of resisting the extraterrestrial invaders, the Race's sheer technological advantage over 1940s humanity means that they keep on giving far worse than they get.
In the sequel Colonization series, the Race's war with Germany follows a similar pattern. Sure, the Germans manage to devastate Race-occupied Poland with nuclear weapons, but the Race does the same thing to all of Germany. This is far more significant; the Race controls about 2/3 of the planet, while Germany has no territory outside of Europe.
Post-Apocalypse novel Malevil features a battle between the six defenders of Malevil with rifles and shotguns against twenty rag-wearing, half-dead, pitchfork-carrying refugees devouring their wheat crop. They didn't want to massacre the wretches, but when one kills Manchild Momo the need to defend their livelihood mixes with the desire for revenge in a massive Shoot the Dog moment.
In Fate/Zero, in order to gauge Alexander's prowess, Kotomine orders his Servant Assassin, who is split into several forms, to attack Alexander head-on. Even though Assassin had no chance against Alexander, they might be able to kill Waver and Irisviel. Sure enough, Alexander obliges and uses his most powerful attack on the group of assassins: Ionian Hetairoi - Army of the King. A hundred Assassins? Meet the army that nearly conqueredthe world.
The hundred faces among the Hassans had forgotten about the Holy Grail at this moment. Forgetting victory and the mission of the Command Seal, they had already lost sense of themselves as a Servant. Some ran away, while some screamed fruitlessly. Some others stood dumbly on their spots. The panicked mob of skull masks were indeed just a group of rabble. “Trample them!!" Rider commanded without hesitation. The collective roar of the Ionian Hetairoi echoed in response. The peerless army that once swept across continents once again thundered across the battlefield. This was no longer a battle. It was a massacre.
Halo: The Fall of Reach: The titular planet falls hard to the Covenant; while the UNSC's "big sticks" did manage to really put the hurt on the final Covenant assault wave, the battle overall is definitely one-sided to say the very least. Not even the deployment of nearly every remaining Spartan-II is enough to defend even one generator; instead, all humanity can do is buy time to save less than 2% of the billions living on the planet and protect the location of Earth. While the Covenant also take heavy casualties from the battle, they have more than enough ships and soldiers to make up for any losses, unlike the UNSC.
Syrio Forel, unarmored, took down and/or killed five lighty armed and armored guardsmen with a wooden sword, in a matter of seconds. However this was ineffective against the Kingsguard ser Meryn Trant, whose full-body plate armor rendered Syrio's attacks useless. It is not shown, but implied, that Syrio suffered a fate similar to the ones of the guardsmen.
In the backstory, there's Aegon Targaryen's conquest of Westeros. The armies of the Seven Kingdoms vastly outnumbered the Targaryen forces. Aegon, however, had three very large, Nigh Invulnerabledragons whose fiery breath could melt solid stone. In the entire conquest, there was only one battle in which all three dragons were used. It was called the Field of Fire.
Griff and the Golden Company against the defenders of Griffon's Reach.
Griff expected to lose a hundred men, perhaps more. They lost four.
Stannis retaking Deepwood Moat from the Ironborn. Stannis has 4,500 men, against Asha Greyjoys 200. The result, only 9 ironborn are left alive, including Asha.
Jesus Christ versus the Global Community Unity Army is such a battle, since not only is Jesus and His heavenly army unkillable (the Dramatic Audio presentation of the book had missiles fired at Him with no success), but also Jesus is armed with the One Hit Poly Kill weapon which is The Word of God, which the enemy has no defense against.
The anti-climactic Satan's Other Light army vs. God battle in Kingdom Come was over in an instant. All that preparation and God just smokes Satan's army into ashes in seconds.
The same applies in Wendy Alec's Chronicles of Brothers series, where Lucifer talks a good fight but every time he resorts to open war with Heaven or Christos, he gets creamed. You wonder why he bothers...
In Wearing the Cape, Hope/Astra nearly loses in her first hero/villain fight, against Brick, a superstrong gang-banger supervillain—partly due to inexperience, but also due to being handicapped by an intruding second supervillain. Later she gets a rematch and the fight is so one-sided Brick doesn't land a single hit, as a dramatic way of showing how much she's progressed.
In the last Percy Jackson and the Olympians book, The Last Olympian, there is the fight between the Minotaur, fully armoured and leading a legion of demigods and monsters, vs Percy Jackson. Percy wins. Oh, not just against the Minotaur, but against the whole legion, due to him having the Curse of Achilles.
In Sienkiewicz Trilogy Michał Wołodyjowski is this trope. In first two books he is just a minor character, which doesn't stop him from almost killing main antagonist of the first, subverting I Am Not Left-Handed in the process, and utterly humiliating main character of the second, all without breaking a sweat.
In the Star Trek: Destiny trilogy, much time is spent on a subplot in which the president of the United Federation of Planets tries to convince every other major nation to aid her against a full-scale Borg invasion. Some refuse, but eventually the combined forces of the Federation, the Klingon Empire, the Romulan Star Empire, the Imperial Romulan State, the Cardassian Union, the Breen Confederacy, the Gorn Hegemony, the Ferengi Alliance, the Talarian Republic and the Orions mass to face the Borg. Then the Borg armada destroys the entire combined fleet in minutes.
In The Oregon Files book Corsair, the crew of the Oregon must go up against a fully armed Libyan destroyer to rescue the American Secretary of Defense being held hostage on it. After using a massive oil tanker to hide their approach, the Oregon pulls broadside, takes a couple rounds, then proceeds to blow the living crap out of the destroyer as the Oregon's captain rescues the Secretary from the besieged vessel. The only thing that prevented the Oregon from sinking the destroyer was that it would have caused a (further) international incident. Still, that didn't stop the Oregon from disabling it.
The crucial Space Battle in Harry Harrison's Starworld involves The Empire and La Résistance fleet squaring off. The Earth fleet is better equipped (holo-screens) and armed (having a good number of nukes), while the rebel fleet is made up of a few dedicated warships with crews that have defected and the rest are former transports refitted for war. All space combat is done using missiles, which are used offensively and defensively (as screens and mines). Energy weapons have extremely short ranges and can only be used planet-side. However, rebel engineers have a trick up their sleave in the form of mass drivers. The main guns are built to run the length of the ship, accelerating plain old cannonballs (without explosives) to extreme speeds. The protagonist (himself an engineer) helps them solve a programming issue with the magnets, which previously prevented them from spamming cannonballs. After some maneuvering and missile launches (which were all intercepted by other missiles), the rebel fleet gets close enough to unleash their Secret Weapon. The opening volley cripples the enemy fleet. The rebels then move in for the kill, opening up with the smaller, turreted mass drivers that fire explosive bullets, tearing the enemy to shreds. Oh, yeah, and there were no casualties on the rebel side. Nobody cheers on the winning side, though, as many of those officers used to be friends, including the two admirals.
Diane Duane's Star Trek novel My Enemy, My Ally features the ChR Battlequeen, a Romulan-operated D7-class cruiser, going against the USS Inaieu, that is practically the refitted Enterprise ten times bigger and with four nacelles. Battlequeen was disintegrated faster than it takes to read the phrase from the book "Battlequeen is destroyed".
In Exiles of ColSec, Cord—who's bested better-trained hand-to-hand combatants by virtue of being Unskilled ButReallyDamn Strong—is nonetheless no match for Lamprey's extensive combat training. In fact, he would have almost certainly gotten killed if Samella hadn't intervened.
Trapped on Draconica: Daniar's rematch with a drug runner-turned soldier lasts about five seconds. The narration describes it as 'the shortest battle of her life'.
Almost every fight in The Dark Tower ends this way. No matter how much a villain is played up as a possible rival to the main characters, they're all defeated handily with minimal fuss.
Swedish novel Midvintermörker is pretty much all about this. While the Swedes win some battles, and destroy a supply ship in Slite harbour, the outcome is never really in doubt. Russia wins.
In the Sherlock Holmes short story "The Solitary Cyclist", local bully Woodley makes the mistake of picking on Holmes. Holmes comes out of the fight with a cut lip and a bruise on his forehead. Woodley is taken home in a cart.
In The Hunger Games, this is what Finnick's Games became once he received a trident from sponsors. According to Katniss, "within a matter of days the crown was his."
Every fight that Gaia gets into in Gone ends up being this trope. Drake occasionally has one of these, too, most notably in Fear when he and the coyotes killed Howard.
In Robert A. Heinlein's Between Planets the Venus stratospheric rocket shuttle Little David is retrofitted with lost First Empire technology and faces off three state of the art Federation space warships. The chapter builds with the crew of the Little David getting more and more tense as they approach Mars then detecting the Federation ships and englobing them its force field projector. The "battle" (sic) is over.
Occurs in the section on cosmic powers of How to Be a Superhero, where Captain Cosmic uses the power of a single eyebrow to defeat the collective forces of the Crime Kings (and obliterate the Earth in the process).
In Larry Niven's Known Space saga, the first attempt to invade Earth's solar system by the Kzinti resulted in one of these. The Kzin's telepathic spies kept telling their commanders that the humans had no weapons. No weapons at all. But only because the humans didn't see eight hundred petawatt launching lasers, magnetic rail launch cannons, and fusion drive engine exhaust plumes as weapons anymore.
On the meta level this is known as "Kzinti lesson", or more general as the First Law Of Space Combat: "Any propulsion system that makes space travel dramatically interesting, would make a fantastic weapon".
Empire from the Ashes gives us the Achuultani scout fleet in the second book. They're in the middle of the final assault on Earth when one of Colin's revived Imperial Guard ships drops in and effortlessly mops the Achuultani fleet out Earth space in a matter of seconds.
The entire story of Blood Song, by Anthony Ryan, was a How We Got Here of how the main character, Vaelin, a brilliant warrior, ended up on a ship bound by honor to duel "The Shield", by all counts another brilliant warrior, to the death. 600 pages later, we finally arrive at the long-awaited duel, wherein Vaelin immediately breaks The Shield's sword in half and then knocks The Shield unconscious.
In Heart of Steel, Alistair's second battle with Rampant!Jim amounts to this, after Alistair has regained his network access and thus his stronghold defenses, the lack of which contributed heavily to his defeat the first time around.
In the Revanche Cycle, Felix — wrongly accused of espionage and facing his death in a gladiatorial arena, challenges Mayor Veruca Barrett to come down and fight him herself. Bad move. Turns out she's a skilled knife-fighter who regularly shows off for the bloodthirsty crowds, while Felix himself has never been in a fight in his life. It's over in seconds.
In The Red And The Rest, Hammerstein boasts that he has never lost a fight. Resident badass Melchizedek beats him nearly to death while reasoning that this means Hammerstein hasn't been in enough fights. In their rematch, Mel leaves Hammerstein unconscious and bleeding on the ground in a split second by attacking during the latter's Transformation Sequence.
The High Crusade has one bit which pits invading aliens against medieval Englishmen. It's a complete slaughter... for the aliens, as EMP doesn't work against people with swords and longbows, and the aliens are absolutely hopeless at close combat.
The long war between Britain and the United States presented in Harry Harrison's Alternate History WankStars and Stripes Forever is one long Curb-Stomp Battle due to the United States' overwhelming technological and tactical superiority - by the third book, the Americans are almost 100 years ahead of the British, having World War I-era battleships and tanks in 1870. In the course of the series, there are only three notable times where the British actually have the upper hand: the British army capturing a Southern town (somewhat accidentally, as they were intending to capture a Northern outpost), a Highlander regiment capturing a fort near New York, and a British ironclad sinking an American one. Every other battle in the series, all resounding American victories.
The Gods Are Bastards gives us Vadrieny (an archdemon) versus Gabe (a half-demon, and even his demon side wasn't that powerful):
Teal: We hit him with the planet.
At one point in Star Trek: The Eugenics Wars Khan rescues Gary Seven who was captured by Soviet soldiers in Moscow. Khan single-handedly takes down several Soviet soldiers with Chakrams.
Isis in her human form also neutralizes two Sikh bodyguards before they even notice that they're under attack.
In the Nameless War the ships of the Third Fleet are effectively caught and destroyed at their moorings when the Nameless, make re-entry into real space far closer to the asteroid the fleet's base is built onto than is possible with human technology.
From the other books, there's Skaffen-Amtiskaw vs. anyone who got in his way, the Edust Assassin vs the Chelgrian leaders, and titular Excession vs. anything and anyone that attempted to mess with it.
The Fatal Dream: This is what usually happens when the Pteranodon attacks someone, but it gradually becomes less so as the narrative goes on.
In The Age of Misrule, this is what the incoming supernatural forces did to the UK armed forces in the first book. Because of Immune to Bullets taken to include all non-magical weapons, the monsters took no injuries while the armed forces were slaughtered to a man.
In Foundation, that is the fate of the bulk of the Kalganian navy at the hands of a much smaller Foundation fleet the Second Foundation is behind everything
Commonly used early on in David Gemmell's stories to illustrate just how badass the hero is. Waylander, in the Drenai saga, gets one of these as the first scene in two out of three of his books.
In the Chinese web novel series The King's Avatar most fights in Glory with the main character end up like this. It helps that he's been playing the game for ten years and is a veteran in the pro gaming scene.
In their first official outing as a team, the Inscrutable Machine fights Sharky, a kid from their school who wants to prove his strength. They knock him unconscious in seconds, and the rest of the fight becomes about keeping the heroes from arresting them too.
Chimera was one of the most powerful and dangerous villains thirty years ago, only put down for good when the hero Evolution completely annihilated him. A small part of him survived, and he eventually regenerated and returned to make a name for himself again. He tried to rob a bank, but Generic Girl destroyed him in fifteen seconds. Penny's mom timed it.
Speaking of Penny's Mom, she used to be the Audit, a Badass NormalTerror Hero who used Awesomeness by Analysis to weaponize statistics. In the third book, one of Penny's classmates, Cassie, decides to try challenging her to a fight. While Cassie is grandstanding and charging up her electricity powers, the Audit steals an eraser from her daughter's pencil and flicks it at Cassie's head, which makes Cassie trip over her own feet and fall to the ground.
Cassie: Did you know I would trip? The Audit: You have had a growth spurt in the last six months, and your kinesthetic sense is not yet used to your longer legs and changed center of gravity. There was a two percent chance of concussion or worse trauma. That would combine observational and operant conditioning to reduce the chance of more in-class incidents by other students by sixty-nine percent. If I had taken a step forward before throwing, you would have hit the desk at a different angle, falling head-first and increasing the likelihood of injury to fifty-fifty. Despite the usefulness as a lesson, I decided that was morally unacceptable.
The Silmarillion has Fingolfin and Feanor doing this to entire armies.
The Vagrant (first book of The Vagrant Trilogy): Once the Usurper's commander of the Knights of Jade and Ash remembers his past as a commander of the Seraph Knights, he walks right into the lairs of the Uncivil and then the Usurper, delivering Gamma's last message, which kills both the Uncivil and the Usurper with ease.
The second book of The Girl from the Miracles District has the mooks make the mistake of assaulting Nikita once when she's accompanied by a Badass Biker gang, and once when she's in the house of an immortal, his huldra wife and their three sons. Both end with the good guys effortlessly wiping the floor with their enemies.
The third book of The Spirit Thief sees Josef try to fight the Lord of Storms, an Anthropomorphic Personification of a hurricane. Suffice to say, it takes a literal divine intervention to stop the Lord of Storms from completely destroying him.
Through being obsessed with Boring, but Practical, the Romans crushed zombie outbreaks with such effective regularity that by the end of their reign the undead weren't even taken seriously anymore. The history section of the book notes that, "This was the last recorded Roman Zombie attack of note, as others were so short or not well enough described to count."
World War Z: Once the American campaign to retake the country got underway, environmental hazards, rogue survivors, abandoned traps, feral children, and sickness were statistically much more likely to kill their soldiers than the zombies. Individual soldiers with kill counts in the thousands aren't even considered notable except as an indicator of length of service.
In Victoria, the running air battles as the Lady Land Azania attempts to fend off an invasion by the fanatical Christian domininists of the Northern Confederation. While high-tech Azania has better planes than their reactionary enemies, their inadequately trained pilots cannot make the best use of them, and end up defeated in detail by the stone-cold veterans of the Confederation's Legion Condor.