History Main / CavalryBetrayal

-->-- '''Grand Apothecary Putress''' WhamLine before destroying a united Horde and Alliance force at the Wrathgate, ''VideoGame/WorldOfWarcraft''

* ''Manga/{{Hellsing}}'': Shortly after Millennium attacks London with a battalion of [[NinjaPirateZombieRobot Nazi vampires]], an army of some 3,000+ knights in helicopters and gunships are deployed by [[ChurchMilitant Section XIII Iscariot]]. The arrival of this force catches the Millennium forces initially off-guard and relieves the surviving population of London and they are greeted as saviors -- until their leader Enrico Maxwell, who has at this point [[DrunkWithPower gone far off the deep end]], issues the order to kill everyone in London, civilian and vampire alike, resulting in the Iscariot forces indiscriminately mowing down everyone.

* Wrestling/{{WCW}} Bash at the Beach '96, which, in turn precipitated the biggest FaceHeelTurn in pro wrestling history. After Wrestling/{{Sting}}, Wrestling/RandySavage, and Wrestling/LexLuger had taken a beating from The Outsiders (Wrestling/ScottHall and Wrestling/KevinNash), Wrestling/HulkHogan comes down to the ring, ostensibly to help out Sting and Savage (with Luger having been knocked out)... and then he leg dropped Randy Savage, revealing himself to be the Outsiders' mystery partner and heralding the beginning of the Wrestling/NewWorldOrder.

* ''Film/RevengeOfTheSith'': A Clone Army led by Master Yoda is sent to Kashyyyk to repel [[MemeticMutation the droid attack on the Wookiees]]. But then Order 66 is issued and the clones turn against Yoda. Since the Wookiees are friends with Yoda, they side with him and turn against the clones. The result: The droid separatists are driven off, Yoda escaped Kashyyyk thanks to the Wookiees, but most of the Wookiees are captured by the clones and enslaved by the newly-created Galactic Empire.

''Benzaie''': *Punches out Nostalgia Critic*

* ''VideoGame/StarCraft'': The intro video to ''Brood War'' expansion culminates to this from the point of view of the colonial marines being slaughtered by the Zerg. Thinking Admiral [=DuGalle=]'s Alexsander is there to lend them air support, he simply disengages from the conflict after observing the slaughter with Stukov on the bridge, leaving the colony to be overwhelmed.

Subtrope of HopeSpot and FriendOrFoe. Compare with: CavalryRefusal, ChangedMyMindKid, BetrayalByInaction, BigDamnHeroes and AlwaysABiggerFish.

* Popular theory holds that the Soviet Red Army pulled such an act during the Warsaw Uprising, when Polish resistance fighters sought to rid the capital of the Nazi General Government and military. Research from Polish historians shows this as a complicated and narrow aversion: the Red Army certainly ''did not'' actively fight the Polish resistance in the Uprising (as they had, for example, during the onset of the war when they invaded Poland alongside Germany)--they didn't fight anyone at all, and in all likelihood, were badly spent from edging out bloody victories against the largest German army groups of the war during the liberation of Belarus. The Red Army instead decided to stand aside during the battle (despite some propaganda broadcasts from Moscow suggesting Soviet support was imminent). Soviet tank units were denied fuel for advancing even if they wanted to, and only after repeated pressure from the Western allies did the Red Army offer basic assistance to the Polish Home Army [[http://en.wikipedia.org/wiki/Warsaw_Uprising#Soviet_stance]]. Soviet leadership, Stalin included, chose to focus on other fronts and take Warsaw afterwards--possibly reflecting the very high level of distrust between the parties involved.

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* ''VideoGame/StarCraft'': The intro video to Brood War expansion culminates to this from the point of view of the colonial marines being slaughtered by the Zerg. Thinking Admiral DuGalle's Alexsander is there to lend them air support, he simply disengages from the conflict after observing the slaughter with Stukov on the bridge, leaving the colony to be overwhelmed.

* One of the Video Examples for this page shows an example from ''Series/Firefly'' where Malcolm Reynolds is an Independent (Browncoat) trying to call for reinforcements, who pull out at the last moment because the Alliance had just sent in forces so large that they would most likely have annihilated both the ground troops and the cavalry.

* Poor Raphtalia had to endure this in her Backstory, which is fully explored in Episode 15 of ''LightNovel/TheRisingOfTheShieldHero''. After losing her parents in one of the Waves, she tries to keep everyone's spirits high, and even gets them on the road to rebuilding their town. A force of knights arrive that everyone initially thinks is going to help them. '''They're not.''' They're there to slaughter all the adults and sell all the kids as slaves, which leads directly to Raphtalia's hellish ordeal under the sadistic lord she was enslaved to before meeting Naofumi. To say that this experience [[BreakTheCutie broke her]] would be an understatement.

* In ''Film/WildWildWest'', Bloodbath [=McGrath=]'s men wait for some assistance from Arliss Loveless. However, his "help" turns out to be a tank that blows them down. Loveless's reasoning? Bloodbath and his men surrendered at Appomattox in the Civil War.

* Wrestling/{{WCW}} Bash at the Beach '96, which, in turn precipitated the biggest FaceHeelTurn in pro wrestling history. After Wrestling/{{Sting}}, Wrestling/RandySavage, and Wrestling/LexLuger had taken a beating from The Outsiders (Wrestling/ScottHall and Wrestling/KevinNash), Wrestling/HulkHogan comes down to the ring, ostensibly to help out Sting and Savage (with Luger having been knocked out)...and then he leg dropped Randy Savage, revealing himself to be the Outsiders' mystery partner and heralding the beginning of the Wrestling/NewWorldOrder.
* Happened at the creation of the (in)famous Alliance, while Wrestling/ChrisJericho & Wrestling/{{Kane}} were being beaten down at the hands of the nefarious WCW crew, Wrestling/LanceStorm and Wrestling/MikeAwesome. Then, holy shit, Wrestling/RobVanDam and Wrestling/TommyDreamer show up and join in! Then a bunch of WWF guys ran in for the save: Wrestling/{{Tazz}}, Wrestling/{{Rhyno}}, Justin Credible, Wrestling/{{Raven}}, Wrestling/TheDudleyBoys... wait a minute, what do ''all'' those guys have in common? Jericho & Kane were promptly pronounced screwed when Wrestling/PaulHeyman left the announce table to proclaim that this invasion had been [[PunctuatedForEmphasis TAKEN! TO THE!]] [[Wrestling/{{ECW}} EXTREEEEME!]]
* Wrestling/MattHardy running down to ringside with a chair during his brother Wrestling/{{Jeff|Hardy}}'s match with Wrestling/{{Edge}} at the 2009 Royal Rumble. This one still managed to surprise because Matt had legitimate gripes with Edge and even if you did not know that, Edge had sent Matt packing from Monday Night Raw after stealing his girlfriend (well, Kane stole her first but we digress).

* At ''Wrestling/{{R|ingOfHonor}}OH [=SoCal=] Showdown'', Wrestling/ColtCabana ran out to stop Scotty 2 Hotty from performing his finishing move, the worm, on guest referee Johnny Fairplay, only to give Fairplay the worm himself.
* At ''Shine 16'', Jessicka Havok, Wrestling/AngelinaLove, Amber O'Neal and Serena Deeb ran out to save then new Shine Champion Wrestling/IvelisseVelez from Made In Sin, who were none too happy with Velez for retiring [[PowerStable Valkyrie]] leader Radiant Rain. After Havok, Love and O'Neal dealt with April Hunter, Wrestling/AllysinKay and Taylor Made, [[TheMole Deeb hit Velez over the head with the title belt]] before retreating with Made In Sin and replacing Rain as Valkyrie's leader.

* The player character pulls this off in the endgame of ''VideoGame/FalloutNewVegas'' if they're fighting for Mr. House or an Independent Vegas. While you and the Securitrons are fighting alongside [[TheFederation the NCR]] for the majority of the battle, you're also secretly trying to activate the SealedArmyInACan. Once the [[TheHorde Legion]] is routed, you then have to get General Oliver to retreat, either through force or through diplomacy.

* ''Film/RevengeOfTheSith'': A Clone Army led by Master Yoda is sent to Kashyyk to repel [[MemeticMutation the droid attack on the Wookiees]]. But then Order 66 is issued and the clones turn against Yoda. Since the Wookiees are friends with Yoda, they side with him and turn against the clones. The result: The droid separatists are driven off, Yoda escaped Kashyyyk thanks to the Wookiees, but most of the Wookiees are captured by the clones and enslaved by the newly-created Galactic Empire.

* In ''Literature/{{Worm}}'', [[TragicMonster Echidna]] has stalemated [[WorldsStrongestMan Eidolon]] and her clones are whittling down the combined forces of [[EnemyMine the Protectorate and the Undersiders.]] Then the Travelers, the Undersider's allies, show up to help, but [[TheUnfettered Trickster]], the leader of of the Travelers, betrays ''everybody'' to support Echidna, his {{Protectorate}} and ex-girlfriend.

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[[folder:Fan Fic]]

[[folder:Web Comics]]

* ''Literature/TheCrimsonShadow'': A rare [[InvertedTrope inversion]]. During a naval battle between the Avonese and Eriadorans, ships come sailing over from Baraduine (an island ruled by Avon), making the former celebrate. Instead though they attack the Avonese ships, since it turns out that Baraduine would like to be free.

Basically any instance in which apparent rescuers turn on the heroes -- due to either having a secret agenda or [[FriendOrFoe mistaking the protagonists for bad guys]]. As a subverted expectations trope, most examples will be spoilers.

* A rare example of this happening to the antagonists shows up in ''Anime/MobileSuitGundamSEEDDestiny'' when [[spoiler: [[BigBad Chairman Durandal]]]] tries to reinforce his game-ending super-weapon by bringing up the Home-guard. However, the Calvery in this case happened to be lead by veterans of the [[Anime/MobileSuitGundamSEED previous war]] who'd had enough of [[WellIntentionedExtremist Extremists]]. A few minutes after entering the battle they switch sides, taking a good chunk of the [[BigBad Big Bad's]] forces with them.

* In ''Manga/CodeGeassTalesOfAnAlternateShogunate'', this happens to [[spoiler:the villains; Suzaku and Euphemia's other forces have realized that Perry is trying to make Japan his own property, and as such, instead of helping him, fight alongside Lelouch and the Black Knights against him]].

* In the 2015 anime adaptation of ''Literature/TheHeroicLegendOfArslan'', during the disastrous Battle of Atropene, Arslan is [[HeroicBSOD in numbed shock]] after he witnesses firsthand the bloody destruction. He hears [[spoiler: Kharlan]] calling for him and is initially relieved that a familiar person is close, only to realize that the latter and their troops are not here to help him, but to kill him.
* Poor Raphtalia had to endure this in her Backstory, which is fully explored in Episode 15 of ''LightNovel/TheRisingOfTheShieldHero''. [[spoiler:After losing her parents in one of the Waves, she tries to keep everyone's spirits high, and even gets them on the road to rebuilding their town. A force of knights arrive that everyone initially thinks is going to help them. '''They're not.''' They're there to slaughter all the adults and sell all the kids as slaves, which leads directly to Raphtalia's hellish ordeal under the sadistic lord she was enslaved to before meeting Naofumi]]. To say that this experience [[BreakTheCutie broke her]] would be an understatement.

* In the ''Franchise/LyricalNanoha'' fanfic ''[[Fanfic/TeanasTravels Rise of the Phoenixes]]'', [[spoiler:Jane Smythe does this to Miles Fairbrass and Harry Henriksen.]]
* In ''FanFic/TheCriesOfHaruhiSuzumiya'', [[spoiler:Nagato, in a KnightTemplar-ish act to try and improve the situation, does this to Kyon.]]
* In the ''WesternAnimation/LiloAndStitch''[=/=]''Franchise/StarTrek'' fanfic ''[[FanFic/StarlightSeries Starlight]]'', [[spoiler:Jumba initially thinks Experiment 628 has come to save them, until he reveals his allegiance to the Borg.]]

* In the 'movie-within-a-fanfic' of ''Fanfic/MovieNightAtFreddys'', Foxy is betrayed by [[spoiler: his own crew]] when a thunderstorm threatens their ship.
* One takes place in the appropriately titled cavalry battle of the U.A. Sports Festival in ''Fanfic/MyHeroSchoolAdventureIsAllWrongAsExpected''. All of Class 1-A agrees to assist each other when possible against the other students and to not attempt to steal each other's points unless doing so is absolutely necessary to advance to the final round while 1-A is in possession of all the points on the field. [[spoiler:Todoroki's group betrays the agreement after his mistake allows Monoma to copy his Quirk, despite Hachiman warning the entire class about 1-B's abilities, which puts their chances to make it to the next round at risk. Instead of continuously attempting to retrieve their points from Monoma, Todoroki instead switched targets to Hachiman's party after briefly assisting them because the former knew the latter wouldn't think of them as an enemy until it was too late. It's also heavily implied that Todoroki (and likely Yukinoshita too) didn't want Hachiman in particular to get to the next stage because he's just that dangerous of an opponent]].
* In ''FanFic/{{Vainglorious}}'' the Jotuns are about to overrun the main evacuation point for refugees when [[spoiler:the Light Elves arrive and drive them back. However Arthur has become power hungry and tries to steal the Aether from Taylor so he can conquer Earth and the other Nine Realms for himself]]. This is a relatively bloodless betrayal up until [[spoiler:[[TheCavalry the Aesir arrive]] and start duking it out with the Light Elves, with the refugees caught in the crossfire]].
* Inverted (and literal) example in ''Fanfic/GuardiansWizardsAndKungFuFighters''. [[spoiler: During the Battle of the Meridian Plains, Viceroy Khenel's cavalry forces arrive and seem to be about to finish off the outnumbered Rebellion, only to instead turn and attack the forces of the other nobles, Khenel having defected to the Rebellion offscreen some time ago.]]

* The Creator/JeanClaudeVanDamme film ''Second in Command'' ends this way. [[spoiler:The Moldovan armored division that arrived to relieve the US embassy is working for the BigBad; they end up getting their asses kicked by the ''real'' cavalry in the form of [[SemperFi Marine]] [[GunshipRescue helicopters]]]].

** Most infamously at the end of ''Literature/AGameOfThrones'' when [[spoiler:the Goldcloaks turn against Ned Stark]].
** And it happens twice in quick succession in ''Literature/AClashOfKings'', when [[spoiler:Ser Rodrik's forces are betrayed by Ramsay Bolton's forces while they are about to launch an attack to retake Winterfell-- and then mere pages later when Ramsay the Bastard of Bolton betrays Theon Greyjoy, the man who took Winterfell in the first place, after he opened the gates to his "allies."]]
** During the Red Wedding in ''Literature/AStormOfSwords'', [[spoiler:Roose Bolton and his men storm into the room. Catelyn thinks they're there to help her and Robb: however, Bolton is really in league with the Freys, cuts down his fellow northmen, and stabs Robb in the heart.]]

* In ''Literature/TheDresdenFiles'' book ''Changes'' has a double whammy. [[spoiler:In the climactic scene, Martin arrives at a standoff between Susan and the Red King... only to take down Susan, revealing himself as TheMole. Except [[ThanatosGambit he does this so Susan will be able to kill him and become a vampire]], allowing Harry to wipe out the Red Court]].
** Less notable but still important in the same scene was [[spoiler:Lea disguising herself as one of Lords of the Outer Night so she could distract the vampires during the double whammy]].

* ''Literature/ShadowPolice'': In ''The Severed Streets'', Quill is being pursued by the Ripper. [[spoiler:Neil Gaiman]] arrives to pick him up in a car and spirit him away. However, he is actually there to deliver Quill into an ambush.

* A downplayed example in ''Literature/{{Worm}}''. While fighting [[spoiler:Noelle/Echidna]] things are looking bleak, when [[spoiler:the Travelers]] show up and start hammering her. [[spoiler:Sundancer]] in particular has a power that could decisively and permanently end the threat. At least until [[spoiler:Trickster decides he has to grant Noelle's last wish, teleporting the Undersiders and his fellow Travelers into her clutches so she can have her revenge.]]

* In Season 4 of ''Series/{{Lost}}'' [[spoiler:A boat arrives, that the castaways believe is going to rescue them, but in fact brings a team of mercenaries with orders to kill Ben and anyone who gets in their way. Some of them do get rescued anyway, but it doesn't help.]]
** A similar thing happens at the end of season 1, with several characters getting on a raft and finding a boat which they think will rescue them, [[spoiler:but instead it's the Others, who kidnap Walt and torch the raft.]]

* The famous [[WhamEpisode Wham Level]] of ''VideoGame/ModernWarfare2'' ends with one of the most brutal cavalry betrayals in fiction: [[spoiler:the team holds a cabin against an endless stream of attackers while a huge amount of data is copied on a portable hard drive and most of them are dead when all of the data is secured. The last men make a frantic dash down a hillside without any real cover while under fire from lots of automatic rifles, machine guns, and rocket launchers and just 14 meters from the extraction point the player gets downed. When you regain consciousness a few seconds later, your last teammate Ghost drags you by your jacket and finally helicopters of Shadow Company appear from behind you and mow everything down with their miniguns. And when you finally stumble the last steps to the evac chopper, General Shepherd takes the hard drive and shoots both you and Ghost in the chest. The last thing you see is your bodies being thrown in a ditch, a soldier emptying a gas canister over you, and Shepherd throwing his burning cigar at your face]]. You really didn't see THAT coming.
* Likewise in ''VideoGame/FireEmblemGenealogyOfTheHolyWar'', although the lead-up makes it a bit easier to see it coming. Chapter 5 looks like it's going to be the final battle against all of the antagonists, but rather unexpectedly [[spoiler:Velthomer switches sides and starts attacking Freege's army as soon as you get close to Velthomer, double-crossing its allies. All this in spite of the fact that Arvis has now been revealed to be in league with the Loptyr Sect. The chapter ends with Sigurd being led to Belhalla, ostensibly to be cleared of all charges, only to learn that he is still labeled as a traitor and will be killed, along with much of the party (though their fates are mostly left ambiguous).]]

* Towards the end of ''VideoGame/DragonAgeOrigins: [[ExpansionPack Awakening]]'' [[spoiler:you have the option of doing this to the City of Amaranthine. The city has been overwhelmed by darkspawn while [[PlayerHeadquarters Vigil's Keep]] has been ambushed by an even larger darkspawn army. You have the option to burn the city down with ArrowsOnFire, killing all the people and darkspawn that your soldiers have trapped inside, freeing you to save your fortress. Fortunately, you can TakeAThirdOption and save everyone if you have built up the fort enough that it can stand without you.]]

* This happened in the {{Backstory}} of one of the towns in ''VideoGame/DragonQuestVII''. When the monsters first appeared and started terrorizing the town and kidnapping people, one man convinced his neighbors to stand against them. He went ahead to start the fight... and everyone else chickened out. To twist the knife further, this betrayal caused [[spoiler: his sister Matilda to hate everyone, allowing the monsters to turn her into a TragicMonster BarrierMaiden]].
* An extremely rare ''villain'' version happens in ''VideoGame/AssassinsCreedBrotherhood'', during [[spoiler: Sequence 8, where after destroying all of Cesare Borgia's support, he sees one last chance in his Papal Guard army arriving at Roma's gates, only for them to arrest him on orders of the new Pope.]]

* In ''VideoGame/YsSeven'', after getting the last crest from the Sea Dragon on Ruin Island you go back to your ship only to be attacked by a giant Titano, Just in the nick of time the Dragon Knights show up and Save you. [[spoiler: That is only half true however, They are actually here to rescue Aisha and Arrest you for "kidnapping" her and assassinating the King who was murdered mere moments after Adol leaves said King's bedroom]].

* ''VideoGame/{{Sonny}}'' begins and ends with these. At the start, the ZPCI come in helicopters, apparently to wipe the zombies currently attacking you, only to turn on you instead as they don't want witnesses. Finally, the last battle of the game is [[spoiler:against Galiant the Paladin, whose help you just impersonated and who you just helped in taking down Baron Brixus. Veradux reasons he won't accept the truth and turn on them, so he decides to turn on him first and take you along]].

* The Alliance attack on [[spoiler: Vaadwaur Prime]] in ''VideoGame/StarTrekOnline'' involves your ship attacking defences closer and closer to the planet, calling in one wave of allied forces from different factions each stage. One wave joins the enemy instead. [[spoiler: It is the Kazon -- Maje Sessen had secretly suborned most of them.]] This doesn't really work out for them, as the betrayal was predicted and a contingency worked out (some Hirogen are happy to hunt [[spoiler: Kazon and Vaadwaur]] for a while) -- and if called in early enough, it even leads to a ''genuine'' Cavalry moment ([[spoiler: a small group of Kazon show up a stage later to fight beside you, as they found the betrayal dishonorable.]]).

* The PlayerCharacter themselves can do this in ''VideoGame/PathfinderKingmaker'' during the Kellid invasion. Your patron, Lady Jamandi Aldori of Restov, goes to fight them and [[GondorCallsForAid calls for your army to join her]], but you can choose to go chasing after [[spoiler:Tristian]] instead ([[spoiler:which is required if you want to complete his RomanceSidequest]]). [[spoiler:Should you do so, you'll finally arrive to discover the opening rounds have already happened and ended in a PyrrhicVictory for Restov: the Kellids have been stopped for the moment, but Jamandi's army is shattered and her adoptive son Kassil died fighting in her bodyguard, and you're in for a ''vicious'' WhatTheHellHero from Jamandi herself.]]

* In ''Literature/{{Worm}}'', [[spoiler:[[TragicMonster Echidna]] has stalemated [[WorldsStrongestMan Eidolon]] and her clones are whittling down the combined forces of [[EnemyMine the Protectorate and the Undersiders.]]]] Then the Travelers, the Undersider's allies, show up to help, but [[spoiler:[[TheUnfettered Trickster]], the leader of of the Travelers, betrays ''everybody'' to support Echidna, his {{Protectorate}} and ex-girlfriend.]]

* Much like [[Manga/{{Hellsing}} the source material]], the Catholic forces in ''WebVideo/HellsingUltimateAbridged'' are being mowed down en masse by Dracula's forces. Unlike the source, however, the Papal Knights are nowhere in sight, the forces under Bishop Enrico Maxwell being comprised of fringe factions, the KKK, and the Sacred Order of the Temple Beth Zion. [[spoiler:The last of these take the hardware Maxwell gave them and fuck right off, leaving the extremists, the Klansmen and Maxwell to their fates.]]
-->'''Maxwell''': [[spoiler:JEWWWWWWWWWWWWS!!]]

* In ''WesternAnimation/{{Thundercats 2011}}'' during TheSiege of Thundera, trusted General Grune shows up toting a FlareGun that seems to bring the enemy [[LizardFolk Lizards]]' WalkingTank fleet to a halt, only for him to perform an InsigniaRipOffRitual and an EvilCostumeSwitch while debuting his nasty new LightningGun, while [[spoiler:trusted General Panthro...''[[DisguisedHostageGambit isn't]]'' and]] King Claudus is stabbed InTheBack.

* ''Anime/NinjaScroll'': Despite what he said earlier about the wisdom of remaining neutral, the lord of the Mochizuki clan turns up with his forces to help the protagonists take on the Devils of Kimon. But when Kagerou reports to her lord, he runs her through with his katana, as he's actually the BigBad in disguise, and has been all along.

* Creator/LloydAlexander's ''Literature/ChroniclesOfPrydain'': In ''The High King'', a powerful ally, who should be the reinforcements the good guys need against the army of the local EvilOverlord, turns out to be a traitor allied with said Overlord. Perhaps a mild subversion in that he pretty much rode into town and announced this a day before the big battle.