History Main / HourOfPower

* ''WesternAnimation/TheTransformers'': The Terrorcons can only remain in their [[CombiningMecha combined form]], Abominus, for a short period of time before a timer forcibly splits them apart. This is a self-imposed limit due to how [[TheBerserker destructive and uncontrollable]] Abominus is. The Seacons of the same series also imposed an automatic timer for their Piranacon combination. The Seacon's shared love of hunting Autobots makes Piranacon unusually intelligent and focused for a combiner, but it also makes him [[SuperPersistentPredator obsessed with hunting his prey]]. Without the timer, Piranacon would refuse to separate and continue hunting until he drained his entire energy supply and shuts down.

* ''Videogame/VampireSurvivors:'' Certain characters have a gimmick where, upon killing a given number of enemies (that increases with each activation), they get thirty seconds of ''massively'' boosted stats and occasionally additional temporary weapons. As of this writing, they are ''[[Videogame/AmongUs Emergency Meeting]]'''s Impostor Rina (who gets decent Speed and Cooldown boosts and a massive Might boost) and ''Legacy of the Moonspell'''s Menya Moonspell, who becomes outright invincible, gets ''triple'' Might, ''triple'' Speed, an extra Weapon, a Cooldown boost, and some Curse sprinkled on top to get even ''more'' enemies coming. You can unlock a permanently-boosted "Megalo" version of each if you kill 100.000 enemies with the regular versions, too (and yes, Megalo Menya is ''still'' unkillable for the whole thirty minutes).

** Freeza's 100% form is a beefed up version of his final form, but since Freeza almost never uses the form, he has zero stamina and burns out all his energy in less than five minutes. In ''Anime/DragonBallZResurrectionF'', his new Golden form has the exact same problem, ironically after he had supposedly learned his lesson from his previous failure. When he's resurrected ''again'' for the Tournament of Power in ''Super'', he has much better control of the form, having spent his time in the underworld meditating and visualising [[spoiler: countless ways to murder Goku.]]
** The FusionDance introduced in the Buu arc allows two characters to fuse into a composite being with the powers of both, but only for thirty minutes before the technique ends and they split apart. If the beings are particularly powerful, it shorts out even sooner. In [[Anime/DragonBallGt GT]], for example, the fusion of Super Saiyajin 4 Goku and Vegeta, Gogeta, is so immensely powerful that he defuses after only ten minutes.
** The dead can be given permission to return to the world of the living, but only for a day. Like fusion above, a powerful character like Goku has even less time if he engages in prolonged fighting. What should have been a day was half that because used up all his energy fighting as a Super Saiyajin 3, forcing him to return early.
** Speaking of which, when he's alive Goku's Super Saiyajin 3 form sorta falls under this trope. Unlike the [=SSJ1=] and [=SSJ2=] forms, [=SSJ3=] burns through Goku's energy reserves at a considerable rate, and eventually [[HeroicRROD his power level starts dropping if he stays in it for too long]]. It gives him an absolutely massive power boost, but it's mainly meant to quickly overpower and dispatch foes that are stronger than [=SSJ2=], but markedly weaker than [=SSJ3=], before his energy reserves have enough time to dip too low. If [=SSJ3=] Goku is in a fight against someone close to his power, and they end up lasting long enough against him for that to happen (such as his fight against Kid Buu), he can end up in serious trouble. However, it's hinted that this limitation happened because Goku wasn't used to having a living body after being dead for seven years, which wasn't as durable and didn't have endless energy like his dead body.
** The Super Saiyajin God form in ''Anime/DragonBallZBattleOfGods'' turns a regular Saiyajin into a God, but only for a few minutes. However, in ''Anime/DragonBallZResurrectionF'', the [[DepartmentOfRedundancyDepartment Super Saiyajin God Super Saiyajin transformation]] appears to be a hybrized version of the God and normal Super Saiyajin forms that does not share that weakness.