Sometimes, {{The Hero}}es are faced with a seemingly insurmountable enemy. Be it a StoneWall that laughs at attempts to harm it or a FragileSpeedster that dodges attacks with lithe grace, some enemies are hard to defeat with standard tactics. They can generally be defeated through brute force, but it's very difficult. The smarter and much easier way to defeat such a foe is to employ clever strategy and some often unintuitive insight.

An OutsideTheBoxTactic is a simple or otherwise overlooked tactic that is particularly effective against a certain monster or type of monster. It is closely related to an AchillesHeel; the difference being that this weakness is not the only reliable way to defeat such a foe. A foe susceptible to an Outside The Box Tactic is still vulnerable to other tactics, but is very weak to this particular strategy. It is primarily a RolePlayingGame trope, but may be found in other types of games as well.

The most famous and common example involves the use of healing magics or other restorative items to harm the undead, examples of which should be listed under ReviveKillsZombie. If this particular application of a technique is the only place where it is effective, it may be NotCompletelyUseless. If the method was [[NotTheWayItIsMeantToBePlayed unintended]] by the game developers, it may be the result of a GoodBadBug. If the method of attack actually involves not attacking the opponent at all, it becomes SheatheYourSword. If it's not hinted at in any way, yet is the only way to defeat the foe, it may also be a GuideDangIt. If it's not the only way to defeat a foe, but it requires ForcedLevelGrinding to defeat it otherwise, it may be commonly thought of as ThatOneBoss or a BeefGate. Outside-The-Box Tactics are often necessary to defeat a PuzzleBoss or the FinalExamBoss.

Contrast LogicalWeakness, when it's immediately apparent what needs to be done, and UnexpectedlyRealisticGameplay, where the tactic ''shouldn't'' be outside-the-box, but is thanks to defying game logic.
----
!!Examples:

[[foldercontrol]]


[[folder: Anime & Manga]]
* This can occasionally come up in ''Manga/OnePiece,'' [[HeartIsAnAwesomePower along with unexpected strengths,]] when a Devil Fruit power sometimes provides an unforeseen advantage against another power. One of the more prominent examples would be low-tier villain Mr. 3, whose power to create objects out of wax ends up temporarily providing the single best countermeasure against poisonous ImplacableMan Magellan. Being able to do this is also stated as one of the marks of a strong fruit user. Since the powers themselves don't change too much as time goes on, the main way to get stronger with a fruit is to figure out more creative ways to use the powers you already have (such as how Luffy exploited his rubber body to develop the Gear techniques).
* In ''LightNovel/ACertainMagicalIndex'', Accelerator is pretty much invincible while his powers are active. However, one of the Sisters found a tactic that he couldn't simply reflect: continuously zap the air around him. This doesn't hurt him, but it does ionize the air and lower the oxygen content. For all his power, Accelerator still needs to breathe. Unfortunately for her, Accelerator figures out what she's up to and resolves to kill her before she can ionize the air to that extent, though he does congratulate her on being one of the few who has ever come up with a strategy that could possibly harm him.
* A large draw of ''Manga/JojosBizarreAdventure'' is their sheer frequency. Rather than [[OnceAnEpisode Once a Chapter]] every now and then, they happen ''constantly''. The manga owes its title in part to the strange powers both the antagonists and the protagonists have, so the mangaka, Hirohiko Araki, spends a lot of time and energy making them into [[HeartISAnAwesomePower viable]], [[WhenAllYouHaveIsAHammer practical]] powers.
[[/folder]]

[[folder: Comic Books]]
* In ''Comicbook/{{X-Men}}'', Sebastian Shaw absorbs any kinetic energy directed at him, even a bullet, so Storm covers him in snow, [[YouFailPhysicsForever which actually saps his energy, due to cold being a lack of said energy.]]
** Interestingly, 15ish years later the X-Man Bishop -- whose powers are similar to Shaw's -- would charge himself up ''by using snowfall''. Bishop, however, can absorb any kind of energy directed at him where Shawn can only absorb kinetic.
* In ''ComicBook/{{Invincible}}'' the main character faces a villain with powers similar to the X-Men character mentioned above; the way the main character wins is he [[spoiler: continues punching the bad guy until he's been overloaded with so much energy it travels through the floor vaporizing his family and emotionally crippling him.]] This is entirely unintentional, and Invincible spends a significant amount of time and effort trying to explain this.
* In ''{{Knightfall}}'', Shondra Kinsolving had the ability to heal using HealingHands, but when combined with her stepbrother, she and he could kill anyone from afar by healing them ''too much'', putting the victim's glands and nervous system on fatal overdrive.
* In an issue of [[JusticeLeagueOfAmerica JLA]], the League fight an Amazo who has the powers of the whole League...on a conceptual level. Every time they bring in more reinforcements, Amazo gets more powerful. The Atom works out how to beat him; he tells {{Superman}} to officially disband the League. Since the League now no longer "exists", Amazo loses all his powers and shuts down.
* ComicBook/TheAvengers once fought a similar robot. They beat it by exposing it to CaptainAmerica, and it absorbed his fundamental goodness. Then it declared that the Avengers were good guys and it didn't want to fight anymore, regardless of the wishes of its creator.
* Then there was the time ComicBook/TheAvengers were fighting the Super-Adaptoid (a power mimic). Captain Marvel (cosmic awareness, FlyingBrick, blaster, and power wristbands that when clanked together would make him switch places with Rick Jones, who had been trapped in the Negative Zone for some time) let the Super-Adaptoid gain his powers: while the mimic was stunned from getting cosmic awareness, Mar-Vell clapped the Super-Adaptoid's newly-formed wrist bracelets together, banishing it to the Negative Zone and freeing Rick.
* In three occasions in ''ComicBook/PaperinikNewAdventures'' the heroes had to face an Evronian SuperSoldier who doesn't need external equipment to [[EmotionEater drain and feed off his opponent's emotions]], and get defeated in novel ways:
** The first time is when Paperinik faces [[NamesToRunAwayFromReallyFast Trauma]], who, aside for having SuperStrength and [[NighInvulnerable taking a rocket to the chest without much damage]], can cause paralyzing fear in his opponents and feed off it, transforming his victims into [[SlaveMook coolflames]]. Paperinik defeats him by ''conquering his own fear'', with the accidental side effect of scaring the crap out of Trauma and [[{{Depower}} depowering him]].
** The second time is when Xadhoom faces Clangor, an Evronian cyborg who can absorb energy attacks and his enemies' emotions. Upon hearing this, Xadhoom lets go just a little of her enormous emotional control-And that small portion of her rage and [[SurvivorsGuilt hatred for herself for letting the Evronian destroy her homeworld]] overwhelmed his emotional absorption abilities and broke it.
*** Clangor implies it's not the first time he's a victim of this trope: he once mutinied, and the Evronians neutralized him with his ''remote off switch''.
** The third happens in a WhatIf story, where Paperinik and American troops have to fight super strong Evronians with accelerated metabolism that feed off negative emotions. When their prototype blabs out too much, Paperinik realizes all they have to do is to stop fighting and start thinking about nice and happy things, resulting in the Evronians literally ''starving to death''.
[[/folder]]

[[folder: Film]]
* [=AT-ATs=] in the ''Franchise/StarWars'' series have thick armor impervious to the blasters on rebel fighters. However, due to their being very top-heavy, a simple harpoon and tow cable can bring them down with ease. They're also much less heavily armored, and therefore more vulnerable, in the ventral aspect, though a competent commander will deploy them in such fashion as to obviate any potential risk thus caused; they're not particularly quick, so a long advance to contact provides more than enough time for their heavy forward-mounted guns to flatten anything which might shoot up at them from below. (Shot-down stray Jedi, of course, notwithstanding -- but it'd take a whole lot of them, even at a rate of one Jedi and one thermal detonator per AT-AT, to make a real difference in any kind of serious battle.)
[[/folder]]

[[folder: Literature]]
* In ''Literature/TheWonderfulWizardOfOz'', water is this to the Wicked Witch of the West.
* In the ''StarWarsExpandedUniverse NewJediOrder'' series, the Yuuzhan Vong villains' OrganicTechnology ships use pinpoint black holes instead of DeflectorShields to "absorb" enemy fire, as well as for propulsion. This prompts a long chain of back-and-forth tactical innovations among the New Republic defenders, ranging from the trivial (unlike shields, voids can't be everywhere at once, so firing at a target from multiple angles will destroy it), to the inspired (an AcePilot can use the singularity to perform a gravity slingshot), to the outright bizarre (a Jedi can telekinetically seize the singularity and [[HoistByHisOwnPetard redirect it onto the ship]], although it requires a ''lot'' of energy).
* ''Literature/EndersGame'' features a virtual adventure game for the local ChildSoldier to play, in which a giant provides a rat a choice whichever of the two provided grails does not contain poison. When Ender has tried both grails and gotten game overs, he controls the rat to jump directly at the giant and kill it. This amazes the commanders because nobody else has ever tried doing the same.
** The [[KobayashiMaru Giant's Drink]] was a deliberately [[UnwinnableByDesign unwinnable]] 'game' designed to show [[ALessonInDefeat how potential soldiers and commanders dealt with losing]]. Both drinks were always different, but ''always'' poison. Ender went OffTheRails with a [[TakeAThirdOption third option]] and broke the game. Although it dealt with this not by glitching and crashing, but somehow creating an entire new world for him to explore.
[[/folder]]

[[folder: Live Action TV]]
* ''Series/StarTrekTheOriginalSeries'' the characters had to deal with an alien that fed off of anger. The Starfleet officers and the Klingons puts aside their differences and laugh it off.
* ''Series/StarTrekTheNextGeneration'', there was a Vulcan device that turned people's anger into a weapon. To counter this, the characters calm themselves down.
* This thinking is what ''Series/BuffyTheVampireSlayer'' is known for, from creating a Slayer army to defeat the FinalBoss to the time she found out whether a demon who claimed to be invincible wasn't rocket proof.
** This appears to be the point of the Cruciamentum, a test undergone by Slayers who make it to 18 which strips them of their usual strength until they are at about the same as an ordinary human, thus forcing them to rely on other skills to defeat a particularly dangerous vampire.
[[/folder]]

[[folder: Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons''
** Casting ''regenerate'' on an Eye of Gruumsh (a one-eyed, mad orc fighter) restores its other eye and negates its magical abilities as well.
** Encounter a badass villain wearing [[ElementalCrafting Dragon Scale armor?]] Cast Resurrection ([[ContinuingIsPainful True or otherwise]]) on the armor, and let him [[OutsideContextVillain deal with the angry dragon]] while you slip past.
*** However, the 10 minute casting time of Resurrection and True Resurrection and the range of touch could be problematic.
** Transmutation school Wizards are the king of this trope. Flesh to Stone, Stone to Mud, Purify Water, anyone?
* in ''TabletopGame/D20Modern Urban Arcana'', you have access to the Resist Energy spell, allowing you take up to 120 damage from energy sources without getting injured. Sounds fairly innocent, right? Well, one energy type is Sonic/Concussion, which is the type of damage inflicted by explosive damage. Resist Energy + a few blocks of C4 + a Demolition check to set them up for maximum damage = a suicide bomber who survives unharmed after blowing himself up.
* ''TabletopGame/{{Exalted}}'' has a [[FunctionalMagic Charm]] (Order-Affirming Blow) that undoes Shaping effects. Guess what? TheFairFolk use shaping effects to create their bodies. OneHitKill.
[[/folder]]

[[folder: Video Games ]]
* In ''[[VideoGame/PLATOMoria Moria]]'' and some versions of ''VideoGame/{{Angband}}'', the spell "Turn Stone to Mud", normally used for digging new passages, can also be used to devastating effect against stone-based monsters such as golems.
* ''VideoGame/NetHack'', a distant cousin, lacks a similar direct equivalent of the Dungeons & Dragons ''stone to earth'' spell, but it ''does'' have "stone to flesh", which makes stone golems much easier to kill -- and also, when used on rocks or boulders, produces prodigious amounts of perfectly edible meat, which non-vegetarian characters can use to stave off starvation.
* In ''VideoGame/BatenKaitosEternalWingsAndTheLostOcean'', the PostFinalBoss has a mountain of HP and therefore will take a long time to defeat normally, but can be instantly defeated by a Spirit Attack, a special type of FinishingMove which can only be triggered as the final attack of a maximum-length combo by the main character, and therefore normal tactics for combo construction like trying to use damage-boosting runs/X-of-a-kinds get thrown out the window in favor of just trying to string together as many cards as possible, and any Magnus that can be used in an offensive combo and isn't a FinishingMove is fair game--even healing magnus.
* In ''VideoGame/DragonQuest'' games, Holy Water is supposed to be used to help avoid RandomEncounters. It can also sometimes be used in battle, but its only effect is to deal a pathetic amount of damage. However, it works just as effectively against [[MetalSlime Metal Slimes]] as any other enemy, and their low HP makes using Holy Water against them a good strategy.
** In ''VideoGame/DragonQuestIII'', Zoma (the game's final boss) can be severely damaged by healing spells or Medical Herbs. In fact, this is the most effective way to attack him. He has to be weakened first with the Sphere of Light, though. [[GuideDangIt There is absolutely nothing in the game that suggests this is possible]]. Even the ''complete walkthrough'' provided in the NES manual didn't say anything[[labelnote:*]]Though in that case, the walkthrough explicitly stops before the FinalBoss and just says "Good Luck!" so as not to ruin the ending[[/labelnote]].
* ''Franchise/FinalFantasy'':
** In the original NES version of ''VideoGame/FinalFantasyI'', Tiamat can be killed with the instant death spell BANE due to a programming oversight.[[labelnote:*]]The chances are very small, however[[/labelnote]]
** In ''VideoGame/FinalFantasyIV'', the Wall (Reflect) spell is integral to defeating Asura, who heals herself twice, at the end of every round, in addition to attacking your party. The catch? You have to cast Wall on her. That way, when she attempts to heal herself, Wall reflects it and heals your party instead. Asura inflicts insane amounts of damage and recovers 2,500-3,300 HP per recovery spell, making her borderline impossible to defeat without this trick.
** The DS Remake presents Dr. Lugae (robot form), who comes with a new tactic: the Reverse Gas. It turns damaging into healing and vise-versa. A player with straight power strategy will easily find him ThatOneBoss with a need to time hitting and healing. If one use this trope, however, the player can intentionally heal Lugae the moments Reverse Gas is in effect. In such case,he'll go down in a few doeses of Cura or Elixer.
** ''VideoGame/FinalFantasyV'':
*** The only practical way to defeat BonusBoss Odin is to use petrification attacks, which will instantly kill him.
*** The Mimic. He'll attack with whatever you attack him with. The key to victory: [[SheatheYourSword Do nothing.]]
*** There's an endgame boss that can learn any Blue Magic spell you cast on it and then cast it back at you. Exploder is a Blue Magic spell that kills that caster and does their current HP in damage: just cast it on the boss and watch it gleefully use its new toy to kill itself.
** ''VideoGame/FinalFantasyVI'':
*** The spell "Vanish". It temporarily causes all physical attacks to miss, but guarantees the next magical attack to hit. [[OneHitKill Death and X-Zone]], normally {{Useless Useful Spell}}s, suddenly become much more appealing. This combo will fail only on enemies immune to Vanish -- since Vanish is supposed to be a ''positive'' effect, there are very few of these. It's also supposed to fail on enemies immune to instant death, but "Vanish = magic succeeds" is checked before "immune to death = death spells fail"; this was fixed in [[VideoGameRemake all subsequent remakes]].
*** ''Final Fantasy VI'' also had the spells Rasp and Osmose, which depleted an enemy's magic points (the latter also restored yours by the same amount). Some enemies were noted ([[GuideDangIt though only at one spot in the entire game]]) to be inherently magical, and unable to maintain their forms if their MP was depleted. You thus had the option of either depleting their hit points or magic points to defeat them; in the case of several that had last-ditch attacks when out of hit points (including ThatOneBoss), removing their magic was the wiser (or sometimes faster) option.
*** From the same game, we had the boss fight against Wrexsoul, which was a GuideDangIt if you wanted to beat the boss "properly" (i.e. with experience and loot). If you didn't care about the loot and just wanted to finish the encounter, you could instead cast X-Zone on the two [=SoulSavers=] while Wrexsoul was MIA. This didn't even need the Vanish bug (above) to work, as the [=SoulSavers=] were actually not immune to the spell. This was ''kept'' in the GameBoyAdvance version of the game (with X-Zone now called Banish).
** In ''VideoGame/FinalFantasyVII'', the Demi spell is surprisingly effective against Emerald Weapon. Demi is a low-level Gravity spell, that does damage equal to 25% of the target's current HP. On most common enemies, it's a waste of time - you can do much more damage with a variety of other, less costly abilities - and most bosses are immune. But Emerald Weapon is not, and, until you whittle his HP down, it can do the 9,999 damage cap to him.
** In ''VideoGame/FinalFantasyVIII'' the Red Giant, a semi-optional boss in Ultimecia's castle, has maxed out physical and magical defenses, making most of the party's attacks severely weakened against him, and he even mocks them for even trying. His only weakness is the same Demi spell mentioned in the previous entry, but that is not the OutsideTheBoxTactic. It's casting Meltdown on it, which causes the Vit0 status effect that completely erases his physical defense, after which point even normal attacks can take him down in a few hits.
*** Meltdown seems try to invoke this in general. You'd think bosses would be immune to Vit0, but in reality ''no one'' is immune to Vit0, not even the BonusBoss Omega Weapon.
** A stone monster in ''VideoGame/FinalFantasyIX'' can be killed instantly by using a Soft (normally used to heal petrified allies) on it.
** ''VideoGame/FinalFantasyX''
*** The final boss can be easily killed by using Zombie and a Phoenix Down.
*** You can do the same with one previous boss (Evrae Altana), who is undead to begin with (though it takes two due to damage caps).
*** Oblitzerator, an early boss, has very high HP for that point in the game; fortunately, you can take 80% of it off by casting Thunder on a conveniently placed crane three times and having the main character use a trigger command. That done, it goes down very quickly.
** In ''VideoGame/FinalFantasyXIII'', bosses are immune to Death... except the final boss, when it's staggered.
** And in ''VideoGame/FinalFantasyTacticsA2'' the Ranger class gains the "Mirror Item" skill, which changes it from ReviveKillsZombie to [[OneHitKO Revive Kills Everything Except Zombie]], as well as the more obvious inversions such as making Potions deal damage. And Remedies (normally a cure-all) now inflict ''everything''. The same effect shows up on an item in ''Final Fantasy XII''.
** A common small scale version of this is using negative statuses and other detrimental states to nullify certain bosses attacks, usually through damage reduction that comes with it. Mostly evident against the BonusBoss. Examples include:
*** ''VideoGame/FinalFantasyVII'': Only go in with one character alive against Ruby Weapon; he can't use Whirlsand, giving you complete control of who he faces. The countering of his attacks with Mime counts too, he'll eventually seal his own doom if set up correctly. Sort of works with Emerald, but look out for the time limit.
*** ''VideoGame/FinalFantasyVIII'': Using zombie on yourself against Omega Weapon; grants immunity to his opening Lvl 5 Death spell (so you can go in at Lvl 100), and reduces damage you take. You can get around ReviveKillsZombie with elemental absorptions.
*** ''VideoGame/FinalFantasyIX:'' Inflict Blind on Ozma. It only uses magic, so it should not impede his performance, but he wastes time curing it anyway. Such time wasting strategies are often the best to beat it. Also, Vivi and Amarant using [[AttackReflector Return Magic]] to send his [[ColonyDrop Dooms]][[TakingYouWithMe day]] back at the source; a true TacticalSuicideBoss.
*** ''VideoGame/FinalFantasyX'': Once you reach his second form, as long as you keep his arms out of action and your team free of statuses, Penance will eventually destroy himself if your team all has weapons with Counter Attack or similar.
*** ''VideoGame/FinalFantasyX2'': Black Elemental. The first playthrough you face him, go in with a Dark Knight and just use [[ActionBomb Charon]]. It has high defenses but not much health, so if your DK has high enough HP, you'll kill it in one. As it's a standalone fight, you don't have to worry about losing your DK either. For Trema, get rid of his MP; he'll be a lot less dangerous for it.
*** ''VideoGame/FinalFantasyXII'': Both Hell Wyrm and Yiazmat have [[TakenForGranite Stone Breath]]. As the victim gets more petrified, the damage they take decreases, so stave off the sorts and stonas as long as you dare; it'll save on them and healing in the long run.
* In ''VideoGame/DeusEx'', you have the option of simply ''running past'' bosses without being required to fight or kill them. [[CombatPragmatist Some can be killed by lobbing a LAM into the room they're in before they even realise what's going on.]]
* In several ''Videogame/ShinMegamiTensei'' games, buffs/debuffs are best used against bosses not for their intended effect, but to goad the boss into losing turns (or Press Turns where applicable) dispelling them instead of attacking.
* ''VideoGame/{{Persona 3}}'' has the 6th full moon boss: Strength and Fortune. The gimmick of the fight is that every turn Fortune will use the "Wheel of Fortune" attack, which has a variety of effects such as inflicting damage, debuffs or StandardStatusEffects on either your party or on themselves. Fear is one of those status effects. At this point, [[GuideDangIt if you're versed enough in fusions]], it's possible to have a Persona with the Ghastly Wail ability, which instantly kills all enemies with Fear. Strength and Fortune are ''not'' immune to this. Provided you know how to manipulate the wheel, the fight can easily become a CurbStompBattle.
* In the ending chapter of ''[[VideoGame/FireEmblemTellius Fire Emblem: Radiant Dawn]]'', the [[ImplacableMan Black Knight]] can be easily beaten by forgoing use of the InfinityPlusOneSword in favor of [[ArmorPiercingAttack using a common]] [[DropTheHammer Hammer]].
* The Berserker in ''VideoGame/LegendOfLegaia'' can be instantly killed via the Nighto spell. It is the only boss vulnerable to this tactic, and is ThatOneBoss otherwise. It is FridgeBrilliance when one considers that Nighto inflicts the Confuse status.
* Get the hit just right, and it's possible to OneHitKill the final form of ''VideoGame/TheLegendOfZeldaLinksAwakening's'' final boss with the boomerang.
* Several enemies in ''[[VideoGame/MetroidPrime3Corruption Metroid Prime 3]]'' can be killed in a single strike of the Nova Blaster augmented by the X-Ray Visor, due to the limitations of their Phazite armor.
* ''VideoGame/MarioAndLuigiSuperstarSaga'' features the Trunkle boss, which dies to one or two hits of the Chopper Bros. attack to the forehead. This is a bit of a GuideDangIt, since it's never mentioned that ''that'' particular move is super-effective on Trunkle, and ''not'' using this tactic to end the battle quickly will lead to a long, hard, DamageSpongeBoss.
* In ''Videogame/SuperMarioRPG'', due to a [[GoodBadBugs design quirk]] Exor is vulnerable to Geno's OneHitKill attack, which all the other bosses have ContractualBossImmunity against.
* ''VideoGame/MegaMan2:''
** Sniper Armors are very vulnerable to Air Shooter and several HumongousMecha are vulnerable to boomerangs.
** During the BossRush portion of the same game, Metal Man dies to [[DifficultyByRegion one]] hit of [[PowerCopying his own weapon]].
* The ''VideoGame/MegaManX'' series continues the trend of its predecessor series. While many bosses have {{Logical Weakness}}es, the Launch Octopus and Flame Mammoth both have one of these - the boomerang attack can cut off Octopus' tentacles and prevent him from using his homing and tornado attacks, as well as being able to cut off Mammoth's trunk so he can't throw around globs of oil he can set on fire and turn them into pillars of fire. You can also [[CycleOfHurting stunlock]] Spark Mandrill and Sting Chameleon.
** There's also [[ShockAndAwe Web]] [[GiantSpider Spider]] from ''X4''. The Twin Slasher does more damage than normal to him, but in order to hurt him ''really hard'', you should fire it at the web he's hanging from, cutting it. He'll drop and [[NotTheFallThatKillsYou go splat on the ground]] for massive damage, although this tends to be more difficult than it was intended since the weapon fires at an angle that usually hits Spider as well when you aim it at the web and when he's under the effects of MercyInvincibility, so is his web.
* ''VideoGame/{{Mega Man ZX}} Advent'': Two of the final boss' tricky-to-avoid attacks can be easily avoided by morphing into Chronoforce (who is otherwise useless for this battle), due to his hard shell blocking the damage from both attacks.
* ''VideoGame/{{MOTHER}}''
** None of the games' final bosses are defeated with traditional methods. In the case of the first two games, they're defeated [[SheatheYourSword not by you attacking them]], but by [[spoiler:singing a song or by prayer]]. The third is mostly [[spoiler:surviving long enough for a cutscene to take place]].
** All enemies, including potentially troublesome bosses, in ''VideoGame/{{Earthbound}}'', are either susceptible to PSI/PK Paralysis, which will completely shut them down and render them incapable of acting for the rest of the fight or crying, which will at least make them much less likely to hit you. This due to the two weaknesses sharing the same stat, but one being inverted.
** Some bosses lack ContractualBossImmunity against PK Flash, a random attack that can instantly kill anything. When it doesn't just make people cry. Or doesn't do much of anything.
** Some [[ThatOneBoss otherwise difficult]] bosses in ''VideoGame/{{MOTHER 3}}'' have some vulnerabilities to certain techniques.
*** The Fierce Pork Trooper. Sure, he's kinda weak against fire, and it ''is'' possible to defeat him with standard melee and PSI attacks, but he becomes much easier to defeat by employing his weakness: DCMC merchandise. Show him some stuff featuring his favourite rock band, and he becomes unable to attack for several turns, turning this into a much easier battle.
*** The Barrier Trio is a normally difficult boss who [[TotalPartyKill throws high-level PSI at your entire party every single round]], when all methods of healing at this point will only affect one party member. However, if you constantly lower their defense with the Tickle Stick and Defense Down, they ''might'' attempt to bring their Defense back up, slowing down their barrage of attacks.
*** On a general note, very few bosses are immune to crying, and their difficulty can be potentially be reduced greatly if you manage to afflict them with it.
* In ''VideoGame/OdinSphere'', Onyx can be glued to the spot with a normally useless "Ooze" potion to stop ThatOneAttack. Since he's so damn big and an Ooze is so small and moves back and forth slowly, Onyx won't be able to do a damn thing except watch his HP go down as you start whaling on him.
* It's a running gag that the final boss, Dhaos, of ''VideoGame/TalesOfPhantasia'' is susceptible to the ''Indignation'' spell. In cameo appearances in later games, he dies to one use of the spell.
* Gespent, a sub-boss in ''VideoGame/WildArms3'', can be killed with a single use of the ''Requiem'' spell.
* The Dominate special ability in ''VideoGame/MassEffect2'', which lets you control organic enemies so they'll attack their allies (basically the equivalent of the normal AI Hacking power), is also inexplicably able to kill husks instantly.
** The Citadel DLC of ''VideoGame/MassEffect3'' has overheard conversations that show the developer thoughts on these. For example, in multiplayer, one of the best tactics of a particular class is to use their tech armor,[[note]]a skill that's supposed to be used to enhance defense and survivability,[[/note]] and then detonating it ForMassiveDamage, rather than the intended use. Or the infeasibility of carrying more than one weapon into combat, when additional weight reduces power cooldown.
* Inferno, the final boss of ''[[SoulSeries Soul Calibur 2]]'', is normally ThatOneBoss... unless you exploit his weakness. Surprisingly for a flaming creature, he has ''no'' ability to avoid throws, and they take off much more damage than any other attacks.
* ''VideoGame/{{Crysis}}'': In the third game, there is a segment in the second mission where a jammer is interfering with your nanosuit, and the way to the jammer is a field with tall grass and many Ceph Stalkers, making the journey a desperate run to destroy it while being slashed on all sides. The thing is, the jammer is just barely visible from the platform that you start that part on. A single shot from the bow with an fragmentation arrowhead means good-bye jammer and straight on to the next objective.
* ''VideoGame/TheWorldEndsWithYou'': Two major flaws of the Time Bomb psych is that it takes a while to actually explode and when it does, any enemy hit flies into the air. Well, the [[BossInMookClothing elephants]], including the BonusBoss one, and both forms of the FinalBoss are slow/immobile and cannot fly in the air. The Time Bomb psych will utterly destroy them.
* ''VideoGame/TeamFortress2'':
** Spies with the Dead Ringer can fake their own deaths while implementing InterfaceScrew to fake out the attacker's killfeed. Weapons with unique/altered killfeed messages like the Holy Mackerel won't show their unique message, tipping off the attacker to the Spy's trickery.
** On the flipside, a Spy is typically unable to face a Soldier or Demoman in direct combat, which is perfectly within the realm of CompetitiveBalance. However, these two classes use weapons that do splash damage to everyone around them, including themselves, and the aforementioned Dead Ringer reduces the damage taken by the Spy. If the enemy is below half health (something [[StatOVision the Spy can innately see]]), a Spy with the Dead Ringer primed can run up into their face and cause him to [[HoistByHisOwnPetard blow himself up]] with a point blank explosion, then skitter away while invisible after [[FakingTheDead faking their explosive demise]]. A Scout can also do this by using the [[CaffeineBulletTime Bonk Atomic Punch]] to effectively become invulnerable for eight seconds, like a mini-Ubercharge.
** Is a Demoman giving you trouble with his Sticky Bomb traps? It's possible to destroy them, or push them out of the way with the Pyro's air blast, but he might just detonate them. A crafty opposing Soldier or Demoman, however, can fire an explosive just short of the sticky bomb carpet, flinging the explosives back at the Demoman who laid them. It's entirely possible to trick a Demoman into [[HoistByHisOwnPetard killing himself in an embarrassing explosion]] this way.
** A Scout under the influence of the Bonk Atomic Punch or an undisguised Spy can creatively position himself to trick the the auto aiming SentryGun into shooting at the Scout or Spy, but hitting the Engineer instead.
** Bonk Atomic Punch-drinking Scouts can get on your nerves as an Engineer, since you can't kill him and he'll probably run away before his drink wears off. Instead, equip the Wrangler, and pin the pest in place with a torrent of firepower until his invulnerability gives out, or use that same firepower to launch him off the edge of the map if it's an open-sided one such as Upward, since he can't be injured but is still affected by KnockBack.
* Like most bosses in ''VideoGame/GoldenSunDarkDawn'', the Ancient Devil is [[UselessUsefulSpell immune to status effects]]. However, its main gimmick is its power to [[BrainwashedAndCrazy enchant your player characters into assisting it]], and ''they'' can be hobbled by status effects. Since the Devil will just enchant someone else if its current ally drops, this is a better way to minimize losses.
* Jormungandr, the second boss of ''{{VideoGame/Magicka}}'', is a giant snake of the burrowing flavor. Normally his head is the only weakpoint, which he holds above the ground when not attacking. While it's not too difficult to hit his head during the attack frames, it's far easier to use a shield spell before he comes up or burrows again because he takes collision damage. Not only does this do more damage than your average beam spell, it also stuns him briefly and then forces him back under ground before he can attack.
* In ''VIdeoGame/PaperMarioStickerStar'', when you find yourself facing a Big Chain Chomp, the solution to the entire problem isn't trying to deplete the monster's HP with your attacks. Instead, you simply pound down the stake keeping it where it is (before you even go into battle with it), and then face it and just wait for it to wake up. It does the rest on its own.
** The giant Cheep-Cheep that's fought at the harbor can either be handled like a TimedBossBattle, or you can simply opt to pop it with a Spike Helmet, circumventing the need to use up your powerful stickers and/or spend coins on the battle roulette to defeat it before it self-destructs on you.
* There are a few examples in the ''VideoGame/SuperSmashBros'' series.
** One of the simpler ones involves the [[MultiMookMelee 15-Minute Melee]], where the player has to survive against waves of drones for 15 minutes. The drones start off with very poor AI, but each replacement drone for one that was defeated has better AI than the ones before. Solution? Don't attack - it's trivially easy to defend against the poor (and seldom-attacking) AI of the early drones, and if they're never defeated, you never have to deal with the ones that might be a challenge.
** One that crosses over into ViolationOfCommonSense and AIBreaker involves the Cruel Melee/Brawl, where the enemy drones have extremely ramped up offense, defense, and aggression on their AI. However, it's possible to abuse that aggression by simply jumping off the stage - the player has ways to recover from that, but the AI doesn't, so its aggression just goads the drones into committing suicide. Flying characters and characters who are momentarily still before using a move to return them to the stage are particularly good at this, as they can remain tempting off-stage targets for longer.
** The Cruel Melee ''[=WiiU/3DS=]'' Miis seem to have wised up to the above tactic, but another one was introduced: spamming Counters. Because the Cruel Miis have insane damage and knockback, and Counters get as powerful as the countered attack, landing a few counters is often enough to earn the requisite [=KOs=] for the achievements, especially if you prepare a custom sword Mii with Counter and buffed defense.
** The Assist Trophy version of Isaac from ''VideoGame/GoldenSun'' does this. Powerful, flashy Psynergy or summons? Nope. He just casts Move, his noncombat utility power... and harmlessly pushes your enemies off the stage for an instant ring-out.
* Some monsters in ''VideoGame/MonsterHunter'' have particularly clever ways to take them down. Is BigEater Nibelsnarf giving you trouble with its charge attacks? FeedItABomb, then [[FishingMinigame fish it out]] to make it vulnerable. Is the Zinogre, which uses Mega Thunderbugs to attack you, on the verge of going into its [[UpToEleven third]] [[TurnsRed Rage Mode]]? Make it trip and catch them with a bugnet.
* In ''VideoGame/SonicTheHedgehog2006'', Sonic's final battle is against the powerful Egg Wyvern. As it's a final boss, it can be a really drawn out, knuckle scraping battle... Or you can [[GoodBadBugs wait for Eggman to charge you a few seconds into the fight, jump up to intercept and toss your Sky Gem at the last moment before you grab for his controls, warp back onto the battle platform and simply wait ten, twenty second for Eggman to be far enough out of range that the game considers him dead.]] Seeing as the battle area is basically a small-ish platform above a bottomless pit that's easy to accidentally run off of [[CameraScrew thanks to the sweepy, swoopy camera]], one of the last things you'd think of doing is tossing around a finicky gem that launches you wherever it may land, but it's not that difficult to pull off and is actually significantly easier to do than the fight itself and an easy S-Rank once you've got the timing down.
** As counterintuitive as it may seem given the fact that the Sonic series is all about speed ''and'' the water is constantly rising with no air bubbles to be found, the best way to handle the boss of Labyrinth Zone in the original ''[[VideoGame/SonicTheHedgehog1 Sonic the Hedgehog]]'' is to just take your time and be deliberate with your moves. Missing a jump ''will'' likely cost you, and getting hit by one of the hazards can easily knock you down a few levels which is more or less the same thing. Don't wait around on a platform longer than you need to, but there's enough time to wait for the path to be clear.
* ''VideoGame/DarkSouls'': The Ceaseless Discharge is probably the largest enemy fought in the game, with enormous amounts of health and overwhelming attack power that will give even high level players a bit of trouble if they get hit. And since he's standing in a pool of lava with you fighting him on a cliff edge, the usual strategy of getting inside his attack range where he can't hit you is impossible. The way you're supposed to beat him is to wait for him to attack, dodge, and then strike the arm/tentacle he used to attack you, killing him via a DeathOfAThousandCuts... or, if you've been paying attention to the level architecture, make him chase you along the cliff and trick him into falling off a cliff of his own, instantly killing him.
* The lava chamber in ''VideoGame/ResidentEvil4'' has three fire-breathing dragon statues you need to disable. The shields placed along the walkways hint that you're expected to fake out the enemies operating each statue and quickly snipe them before they can turn the statue toward you and hide behind it. You ''can'' do that, or you can stand a safe distance away, take a look at the chains each statue hangs from, and [[CuttingTheKnot shoot the D-ring couplers keeping them together]].
* In ''Franchise/{{Halo}}'', the Bubble Shield is a BeehiveBarrier that repulses all forms of ranged damage for several seconds, including plasma bursts and explosives. It is, however, not immune to having a Warthog plow through it and take out its user. That's not this trope. What ''is'' this trope, however, is a player rushing ''into'' an enemy Bubble Shield and detonating a grenade or rocket inside it--since the Bubble Shield prevents damage from passing through ''either side'' of its barrier, this ends up focusing all that destructive potential in an enclosed space, usually resulting in the death of everyone inside the Bubble Shield.
* In ''VideoGame/LufiaCurseOfTheSinistrals'', getting the seventh Dragon Egg requires you to avoid taking damage during the boss "[[IKnowYoureInThereSomewhereFight fight]]" against [[spoiler:Erim]]. You can expertly dodge the boss's attacks until the invisible timer ends...or you can have a character with an Ignore Falling Damage ability repeatedly leap off of the arena, which gives them long enough MercyInvincibility to immediately jump off before taking damage.
* In ''VideoGame/TheElderScrollsVSkyrim'', the "Raise Zombie" spell reanimates an intact dead body and makes it your minion for the next sixty seconds (longer with certain perks). The zombie, by itself, is fairly weak, since it fights only with the armor and weapons it had when it died (that is, if you haven't already looted them). However, since you looted their items, it's only logical that you can put items ''back''. Raise a zombie, put some good armor and a strong weapon on it, and send it in from a safe distance to rip apart foes (for extra VideoGameCrueltyPotential, said foes might have been its former allies!) Once the spell runs out or your zombie re-dies, you can collect its equipment from the ash pile it leaves behind.
** Said zombie can also function as a handy pack-mule: give your heaviest VendorTrash items to the zombie until you get under the CriticalEncumbranceFailure limit (300 lbs. with no perks or Stamina boosts). Fast-travel to the nearest town, and your zombie will follow! However, it will crumble to dust the moment you arrive, but that's fine, you can just pick your stuff up and drag it to the nearest store; you'd rather walk 200 feet with a over-heavy load than the three miles it probably would have been without the zombie.
[[/folder]]

[[folder: Visual Novels]]
* In ''VisualNovel/FateStayNight'', Saber is representative of [[spoiler:King Arthur Pendragon]]. She is vulnerable to items and spells that harm [[spoiler:dragons]] as a result.
[[/folder]]

[[folder: Webcomic]]
* The nature of ''Webcomic/{{Erfworld}}'' means Parson usually has to rely on these to win fights. In fact, that's the whole reason Parson was summoned, to think of tactics no-one else would. And he's ''very good'' at it.
** At one point, Parson describes a tabletop gaming campaign he was creating for his friends which was ''designed'' to be unwinnable in a straightforward manner, [[InvokedTrope just to see what kind of outside-the-box tactics they would use against him]].
* Nearly everything that happens in ''{{Webcomic/Homestuck}}'': Inserting two punched cards together in the appropriate slot to combine the objects they are supposed to make; killing your party so they survive in the afterlife that is connected to all other worlds; replacing your dead self by one of your dream selves (who is supposed to stay where he is until a certain point of the game); using a teleportation power on everything that endangers you to delete it rather than on you to flee; etc...
[[/folder]]

[[folder: WebOriginal]]
* In the ''Literature/WhateleyUniverse'' story "Ayla and the Great Shoulder Angel Conspiracy", Phase sees Bladedancer losing to a power mimic in the school holographic simulator. Phase deals with the power mimic by deliberately letting the mimic get his IntangibleMan power [[spoiler: and then taking the guy into the concrete floor before he learns to use Phase's peculiar flight ability.]]
[[/folder]]

[[folder: Western Animation]]
* ''WesternAnimation/JusticeLeagueUnlimited''
** In the episode "Hawk and Dove", the Annihilator defeats much of the League by feeding off aggression and hostility. When [[ActualPacifist Dove]] faces the machine and neither attacks it nor fights back in self defense, the machine shuts down.
** In the same vein, the android AMAZO mimics both the principal characters' superpowers and weaknesses. After he obtains Superman's strength, he also obtains his weakness to kryptonite. He [[SubvertedTrope quickly evolves past this weakness though]]. Then the trope is invoked a second time as the Martian Manhunter deliberately lets AMAZO copy his powers... which include telepathy, which it uses to read Lex Luthor's mind and discover how he tricked it into fighting the League in the first place.
* The ''SamuraiJack'' episode "Jack vs. Mad Jack" has Jack fighting a clone spawned from his irrational anger. At the conclusion, he catches on, steps back and meditates. With his anger calmed, the clone's power cuts off and it dissipates.
* When Trixie shows up for revenge and curb-stomps Twilight Sparkle in the ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' episode "Magic Duel", Twilight's only chance to fight back is some TrainingFromHell to become as powerful as Trixie. [[spoiler:However, being well-aware that she can't match her power, Twilight instead uses trickery and stage magic, which is Trixie's usual specialty, to defeat her.]]
* ''WesternAnimation/BatmanTheAnimatedSeries'' had Batman vs a RobotMe that was trying to replace him. Batman let the Robot version believe it had ''killed him'' (by throwing him into a bottomless pit); the robot was such an exact copy it suffered a [[HeroicBSOD mental breakdown]] and then destroyed itself for violating Batman's [[ThouShaltNotKill One Rule.]]
[[/folder]]

[[folder: Real Life]]
* To some extent, the evolution of strategy and tactics is one series of these after another. Tactics constantly evolve to adjust to social, political, and technological factors, and in turn affect them in turn. One needs to look only at World War I: the deadlock of the trenches led to the development of quickfire artillery barrages, squad and platoon assault tactics, armored advances, all of which would have been unimaginable to all but the most prescient officers in 1914. The success of the tank led to entire strategies built around it that would dominate the Second World War and the Cold War. What seemed new and outside-the-box in the last war could quickly turn into standard operating procedure in the next.
* In team sports such as American football, on occasion someone will develop a new tactic that other teams simply aren't prepared to defend against when it's first used. If there isn't a rule change to prohibit it, other teams will often copy it or develop defenses to stop it.
** This can also happen to individual players, in team or individual sports. Bobby Orr wracked up high scoring numbers when he entered the National Hockey League by driving directly to the net, a tactic he was able to do because teams weren't used to defensemen being such aggressive scorers and so instead of going after him, they tried to block the pass to a forward that a defenseman would normally make.
* In ancient Greece, armies used the phalanx formation where soldiers would have several lines of soldiers of equal lengths with the front line interlocking shields. Because the shield was held in the left hand, the soldiers on the right of the formation would not benefit from the interlocking shields; to compensate, the toughest soldiers would be placed on the right side. At the Battle of Leuctra between Sparta - the dominant power of the time and with a reputation of having a strong army - and Thebes, the Theban general Epaminondas ordered his outnumbered troops to make unorthodox and uneven phalanxes, putting his elite troops on the left instead of the right and even more forces behind them. The result was the Spartans being overpowered, the Thebans gaining victory and ousting the Spartans as the dominant Greek power, and inspiring Kings Phillip II and [[AlexanderTheGreat Alexander III]] of Macedonia to adopt new approaches in battle tactics, changing the course of history.
* NASCAR driver Smokey Yunick did this so often 'Yunicking the rules' became a phrase. As an example, when rules limited the size of the gas tank, he replaced all the fuel line with exhaust pipe to hold more, adding several more gallons that technically were not part of the fuel tank.
[[/folder]]
----