History AwesomeButImpractical / AnimeAndManga

** Goku's massively powerful Spirit Bomb attack, an attack which draws energy from all nearby life-forms; it's so ponderous it takes ''several episodes'' to fully charge (though this is partially the fault of real-life episode padding) and leaves him wide open to attack, with the added risk of wasting all that energy if he loses concentration. And after all that, it only finishes off a single (canon) opponent in the entire series run.

* ''LightNovel/FullMetalPanic'': The ''Tuatha De Danaan'' (TDD-1) submarine has a revolutionary stealth engine that allows it to go undetected by conventional sonars. The drawback is that the ''TDD-1'' has to stay regularly on dry dock for several days for maintenance. In contrast, nuclear submarines can operate many-long months without refueling.

* It's been stated several times in ''LightNovel/GoblinSlayer'' that a sword can get in about 5 kills before it's too caked in blood and fat to use anymore. Additionally, though longer swords look flashier than a shorter one, they're difficult to swing around in an enclosed space, as we learn very early on in the series.

* ''LightNovel/HighSchoolDXD'': One of Yuuto Kiba's swords, the Destruction Sword, is a {{BFS}} over two meters long and lives up to is name thanks to its destructive aura. The problem is that it is so big and heavy that Kiba can barely lift it and wielding it kills his speed, his greatest advantage in battle.

* The magical weapons in ''LightNovel/IsItWrongToTryToPickUpGirlsInADungeon''. While it can help adventurers that don't know much magic, they are expensive, {{breakable|Weapons}}, and not as strong as actual magic. Welf, possibly the only living person who can make them ''en masse'', refuses to make them for this very reason.

* In ''LightNovel/{{Konosuba}}'', there is the spell [[FantasticNuke Explosion]], the most powerful Detonation-Type Magic. So ridiculously powerful that it's basically a OneHitKill on any target it hits. The drawbacks? Firstly, it can't be used in towns or dungeons specifically because it's too powerful to use in those locations; firing it in the wrong spot could flatten the town the caster is defending, and using it underground will kill everyone either by the explosion or cave in. Secondly, it disintegrates whatever it kills, robbing the caster and their party of any valuable loot and/or bodyparts that the target may be carrying. Megumin, the team's BlackMage, insists on [[MasterOfOneMagic only using her Skill Points to further enhance Explosion's power]], refusing to even increase how much mana she has, never miind [[WillfullyWeak acquire other spells]]. This means that what her mana can't cover is CastFromLifespan, and she collapses and is completely helpless afterwards, and her refusal to learn other skills makes her TheLoad when she can't use Explosion. This PowerfulButIncompetent nature got her kicked out of every adventuring party before Kazuma's, and even Kazuma observes that she's incredibly useless due to her self-sabotaging personality.

* Giga Slave from ''LightNovel/{{Slayers}}''. Sure, you can destroy any enemy/mazoku with it, but chances are you're going to bring on an AssimilationPlot or [[EndOfTheWorldAsWeKnowIt worse]], [[spoiler:be possessed by the (dark) creator of the Universe and most likely ''die from that mere fact'' (as happened to Lina in ''Next'', only surviving when the Lord of Nightmares saw Gourry's UndyingLoyalty to her)]] and if/when you manage to dodge all the above, you still lose your magical powers for a few days [[ArsonmurderAndJaywalking and]] [[LockedIntoStrangeness your hair might turn white until you recover]]. The original novels also have the Blast Blade, a sword that can cut through anything... including any possible material you might try to make a sheath out of. Because of this, it's incredibly difficult to carry the thing around without damaging things (including possibly yourself) by accident. Gourry has to have it magically dulled to make it usable.

* Subverted in the "Phantom Bullet" arc of ''LightNovel/SwordArtOnline'': [[LaserBlade Photon Swords]] in ''Gun Gale Online'' possessed incredible attack power, but were considered this trope due to their limited range, meaning that by the time anyone got close enough to attack with one, they'd be riddled with bullets. Kirito, however, manages to transform the Photon Sword into a LethalJokeWeapon, using his personal experience in VRMMO games that emphasized swordfighting to not only dodge bullets, but [[ParryingBullets deflect them using his Photon Sword]] before going in for the kill. Later on, other players start attempting to replicate his feats with [[DifficultButAwesome limited success]].

* ''LightNovel/UndefeatedBahamutChronicle'' has the Bahamut itself, Lux Arcadia's Divine Drag-Ride. It has a lot of destructive firepower, can easily defeat at least a thousand men, and is a LightningBruiser. Its problems? It's such a huge energy hog that it can literally drain anyone who uses it, and the first time the protagonist uses it, it rendered him into a coma for weeks. Its techniques and firepower are so precise that the protagonist has to use an AceCustom that heavily weighs him down and force himself to be a StoneWall just to perfectly utilize Bahamut.

** Most of the techniques Gotenks comes up with are flashy, but ineffective. His SignatureMove, the Super Ghost Kamikaze Attack, initially appears to be very powerful and effective, but when Buu uses it against Vegito, Vegito demonstrates the attack's FatalFlaw by detonating the ghosts from a safe distance using Ki Blasts, and then mocks Buu for thinking that an attack created by two kids could actually defeat him.

** In Part 5, there's Pannacotta Fugo's Stand, Purple Haze. Purple Haze's ability is producing flesh-eating bacteria that kills people in 30 seconds. The problem is the viruses can't tell friend from foe and Purple Haze himself is ''extremely'' [[HairTriggerTemper short-tempered]] and difficult for even Fugo to control, and ultimately his Stand is a StoryBreakerPower; Fugo absolutely refuses to even use it unless backed into an inescable corner, as the virus could kill him just as easily. In ''LightNovel/PurpleHazeFeedback'', Purple Haze gets a NecessaryDrawback to prevent him from being overpowered.

** Another King Kai technique, the Kaio-ken, multiplies the user's power several times for a short period, but places a severe strain on the body afterwards (to the point where Yajirobe giving Goku a congratulatory slap on the back afterwards caused him intense pain). It's not surprising that he stopped using it after the battle with Frieza, at which point he had the more reliable Super Saiyan form. Interestingly, Kaio-ken ''is'' useful and not that bad... at lower levels. King Kai specifically tells Goku not to go above Kaio-ken x2. However, his battle against Vegeta forced him to crank it higher and his subsequent fight with Frieza even further, thus the severe strain.
*** Speaking of the impractical, we have the Super Kaio-ken, the combination of Super Saiyan and Kaio-ken. Which was seen only once during Goku's filler arc battle against Pikkon (though it is mentioned again in ''Dragon Ball Super''). This technique sounds very awesome, but it is so dangerously impractical that it results in ''instant death'', and Goku [[ItOnlyWorksOnce can't even use it again]], even while dead.

** Really, Gotenks' very ''existence'' is a case of this. While he's undoubtedly one of the most powerful characters in the series, he's far too arrogant and childish to be very dependable. He could have defeated Buu in the Hyperbolic Time Chamber, but was more concerned with showing off and looking cool; by the time [[LetsGetDangerous he got serious]], Buu had already killed almost everyone and he wasted too much time at Super Saiyan 3.

*** In the Granolah The Survivor Saga, Vegeta receives his power-up answer to Ultra Instinct: Ultra Ego. This power gives him the powers of a God of Destruction and has limitless power, and the bonus of the [[CriticalStatusBuff user getting stronger]] when more damage is taken. Vegeta brutally beats down Granolah when the latter gave Ultra Instinct Goku problems, but Ultra Ego has a caveat: It makes the users' ego and battle lust swell up to insane levels, causing them to lose track of the fight, taking hits instead of dodging and resulting in them taking more unnecessary damage. Vegeta is so caught up in his new power and abusing Ultra Ego's buffs more that he doesn't even take notice of the incredible damage his body is taking. He nearly breaks down before he can even use it's power!

* ''LightNovel/HighSchoolDXD'': One of Yuuto Kiba swords, the Destruction Sword, is a {{BFS}} over two meters long and lives up to is name thanks to its destructive aura. The problem is that it is so big and heavy that Kiba can barely lift it and wielding it kills his speed, his greatest advantage in battle.

* ''LightNovel/FullMetalPanic'': The ''Tuatha De Danaan'' (TDD-1) submarine has a revolutionary stealth engine that allows it to go undetected by conventional sonars. The drawback is that the ''TDD-1'' has to stay regularly on dry dock for several days for maintenance.

* ''Manga/NingenFushinNoBoukenshatachiGaSekaiOSukuuYoudesu'': The Sword of Bonds found by Nick and the party. It's a living sword that has incredible power and can not just multiply but square the strength of the user. Made even better by the fact, that it is completely safe, as the creators were GenreSavvy enough individuals who implemented all kinds of safety features so that there would be no risk of misusing him. It would easily be the ultimate weapon in existence, were it not for one little issue: It requires the user to sync with another person, and they have to be on the same wavelength. Which is extremely difficult to do. This issue is compounded by the fact that Nick's party is founded on the basis of distrust, due to each of them having suffered betrayal by the groups they were with before one another, and they have strict rules about how they interact with one another off and on the clock. In spite of that, Nick manages to succeed at syncing with Karan in their time of need and defeat the monsters preventing the party from leaving with the sword.

* This trope covers the special "Invisible 9" units in ''Anime/PumpkinScissors'' in a nutshell, which feature soldiers transformed into supersoldiers in order to counteract design and equipment failures, or to accomplish things that could otherwise be done cheaper with technology improvements. The 908 High Temperature Troopers, for example, use souped-up flame-throwers that are so powerful they cook the users alive. Their "protective suits", rather than actually shielding them from the heat and dispersing it, are instead filled with special chemicals that keep them pain-free and able to function, though they die quickly and in hideous pain if they take the suit off.

*** There's also Notorious B.I.G. It can recover from any injury almost immediately, it will doggedly pursue anything that gained the ire of its user, it will always be faster than anything around it, Not only that, but it can also absorb kinetic energy to become [[{{Pun}} notoriously big]]. It's basically a killing machine even more unstoppable than '''''Kars'''''. The downsides? It possesses nothing in the way of sapience, meaning it relies entirely on instinct; the moment it spots something faster than what it's already attacking, it'll prioritize that thing over whatever it was attacking before. That means if it's falling out of the sky while you're gently floating away, it won't spot you. Also, its user had to ''die'' for it to activate.

* ''LightNovel/FullDive'': Hiro buys a few smoke grenades, which he thinks are the coolest weapons ever. When he is attacked, he hurls one, but it just bounces off the ground without exploding. Reona tells him that he was supposed to light the fuse before throwing it. Given fires in this world are started with a flint and tinder, Hiro angrily asks how is he supposed to light the fuse in the middle of a fight.

* In ''LightNovel/{{Konosuba}}'', there is the spell [[FantastiNuke Explosion]], the most powerful Detonation-Type Magic. So ridiculously powerful that it's basically a OneHitKill on any target it hits. The drawbacks? Firstly, it can't be used in towns or dungeons specifically because it's too powerful to use in those locations; firing it in the wrong spot could flatten the town the caster is defending, and using it underground will kill everyone either by the explosion or cave in. Secondly, it disintegrates whatever it kills, robbing the caster and their party of any valuable loot and/or bodyparts that the target may be carrying. Megumin, the team's BlackMage, insists on [[MasterOfOneMagic only using her Skill Points to further enhance Explosion's power]], refusing to even increase how much mana she has, never miind [[WillfullyWeak acquire other spells]]. This means that what her mana can't cover is CastFromLifespan, and she collapses and is completely helpless afterwards, and her refusal to learn other skills makes her TheLoad when she can't use Explosion. This PowerfulButIncompetent nature got her kicked out of every adventuring party before Kazuma's, and even Kazuma observes that she's incredibly useless due to her self-sabotaging personality.

* In ''LightNovel/{{Konosuba}}'', there is the spell Explosion, the most powerful Detonation-Type Magic. So ridiculously powerful that it's basically a OneHitKill on any target it hits. The drawbacks? Firstly, it can't be used in towns or dungeons specifically because it's too powerful to use in those locations; firing it in the wrong spot could flatten the town the caster is defending, and using it underground will kill everyone either by the explosion or cave in. Secondly, Megumin, the team's BlackMage, insists on only using her Skill Points to further enhance Explosion's power, refusing to even increase how much mana she has. This means that what her mana can't cover is CastFromLifespan, and she collapses and is completely helpless afterwards, and her refusal to learn other skills makes her TheLoad when she can't use Explosion.

*** This goes UpToEleven with the Super Saiyan Third Grade, an "advanced" Super Saiyan form created during the Cell Saga, that increase the bulk, and thus the available power and the energy and stamina consumption, even more than normal Power Stressed forms, with the bulk being so much it actually ''reduces speed'' which makes it useless since all the power in the world does you no good if you can't hit your opponent. Goku and Vegeta figured that these forms were useless on their own,[[note]]Vegeta stuck to Super Saiyan Second Grade, a more usual Power Stressed Form, while Goku, after achieving both forms during training, opts to master the initial transformation and try and surpass Super Saiyan entirely, resulting in Full Power Super Saiyan (a normal Super Saiyan form where the perfect control allows to use more power than Second Grade gave him previously) and Super Saiyan 2 respectively. Vegeta would decide to imitate him the moment he realized what Goku did[[/note]] but the less savvy Trunks found out the hard way when fighting Cell. Way later on in ''Anime/DragonBallSuper'', Caulifla tries to use Super Saiyan Third Grade on Goku, with just as poor results.

*** The Namekian Dragon Balls and Super Dragon Balls manage to make an already impractical in-story cheat code even ''more'' impractical simply by being too big to fit in one's pocket. Namekian Dragon Balls are roughly the size of dodgeballs, while Super Dragon Balls are roughly the size of entire ''[[UpToEleven planets]]''. The latter have an additional problem: namely, they scatter across the ''[[SerialEscalation multiverse]]''.
*** The situation is much more severe with the Black Star Dragon Balls in ''Anime/DragonBallGT'', which scatter across the entire '''[[UpToEleven GALAXY]]''' and will destroy the planet they were last used on should they not be collected and brought back to said planet within a year's time. The upside? Ultimate Shenron, the Black Star Dragon Balls' dragon, is more powerful than the Earth and Namekian Eternal Dragons and thus has a far greater amount of wishes that he can grant. In the same way, Super Shenron is effectively TheOmnipotent.

* When the party are trying to harvest mandrakes in Manga/DeliciousInDungeon, Marcille, who has only read about the subject in textbooks, suggests a convoluted method involving tying a rope to a dog in order to stay out of earshot of their screams. Senshi, who has actual experience dealing with mandrakes, offers an alternative: just cut the head off before it gets a chance to scream. Even though it turns out [[spoiler: letting the mandrake scream before cooking it makes it taste better,]] the party wisely choose to stick with Senshi's method.

** Parts 1 and 2 have Hamon/Ripple abilities. Hamon users can control energy using special breathing techniques, allowing the user to [[GoodThingYouCanHeal rapidly heal wounds,]] [[ArmorPiercingAttack send impacts through solid objects,]] and, most notably, kill Vampires by simulating sunlight. This all sounds amazing, but if one gets past the grueling training (which is supposed to take ''years'' and is very dangerous) they find out that Hamon techniques require uninterrupted and controlled breathing, full range of movement, and proper blood flow in order to use. So if the user is underwater, is having their blood sucked, is frightened, has frostbite, has their limbs tied, is being choked, is in a cramped space, [[ArsonMurderAndJaywalking or is just tired,]] then Hamon is unusable. These all sound like extraneous circumstances, but the Hero is fighting Vampires, more of which can be easily created (by wearing a Stone Mask or ingesting vampiric blood), and the leader of which can [[AnIcePerson freeze anything he touches]]. All of these weaknesses are highlighted in every Hamon fight in part 1.

*** Part 4's The Hand is generally considered to be one of the most powerful Stands in the series. Not only is it strong and fast enough to keep up with Crazy Diamond, but it also has the ability to erase ''anything it wants'' with its right hand. Range isn't a problem either, because it can erase the space between the user and their target. In other words, The Hand is a OneHitKill machine capable of defeating almost anything with just 2 arm swings. Thing is, its user Okuyasu Nijimura is too nice to actually kill people with it, and not bright enough to think up creative uses for it beyond "remove the space between himself and enemy before swinging again" like most people who possess problematic powers.

** Part 6's Highway To Hell forces a target to receive any damage taken by the user. While this sounds potentially quite dangerous, it doesn't protect or heal the user in anyway, effectively forcing them to kill themselves to kill their target. Of course, in the hands of a suicidal sociopath like Thunder [=McQueen=], this isn't too much of a problem.

*** This goes UpToEleven with the Super Saiyan Third Grade, an "advanced" Super Saiyan form created during the Cell Saga, that increase the bulk, and thus the available power and the energy and stamina consumption, even more than normal Power Stressed forms to the point of surpassing the power of Super Saiyan 2, with the bulk being so much it actually ''reduces speed'' which makes it useless since all the power in the world does you no good if you can't hit your opponent. Goku and Vegeta figured that these forms were useless on their own,[[note]]Vegeta stuck to Super Saiyan Second Grade, a more usual Power Stressed Form, while Goku, after achieving both forms during training, opts to master the initial transformation and try and surpass Super Saiyan entirely, resulting in Full Power Super Saiyan (a normal Super Saiyan form where the perfect control allows to use more power than Second Grade gave him previously) and Super Saiyan 2 respectively. Vegeta would decide to imitate him the moment he realized what Goku did[[/note]] but the less savvy Trunks found out the hard way when fighting Cell. Way later on in ''Anime/DragonBallSuper'', Caulifla tries to use Super Saiyan Third Grade on Goku, with just as poor results.