User can put their power into overdrive, boosting their ability way beyond its limit making it stronger or ignoring its weaknesses; sometimes gaining a sudden boost of stamina, strength, speed and endurance in the process of using the power.
It must be a power that the user already has but boosted beyond its limits or so-called limitations at the cost of losing it. After use, the user may face a jeopardous obstruction such as temporary or permanent loss of their powers, a major setback on their abilities, or a crippling/fatal injury.
Ryoma Echizen (Prince of Tennis); via Pinnacle of Perfection
Younger Toguro (Yu Yu Hakusho)
Spyro (The Legend of Spyro)
Calamity Ganon (The Legend of Zelda: Breath of the Wild); via Dark Beast form
Titan (Batman: Arkham)
Venom (DC Comics)
Kōkai Gyoku (Flame of Recca)
Ophis's Snakes (Highschool DxD)
Energy Steroids (One Piece)
Blast Bomb (Slayers); without the use of the Demon's Blood Talismans
In a last ditch effort to defeat Batman, Joker (Batman: Arkham) ingested a massive quantity of the Titan serum and became a powerful abomination...
...but the overdose poisoned him, causing a deadly disease that killed him a year later.
Jackson Chappell (Batman Beyond) took a massive infusion of Venom in an attempt to defeat Batman. While he gained great power, the overdose eventually turned him into a brain-dead vegetable.
Igor Planter (Black Cat) gained the power to control plants via drinking the Spirit Drink, but due to incompatibility, he shriveled up shortly afterwards and died.
Gyanza Rujike (Black Cat) boosting his muscles to the absolute maximum, but due to him being untrained, he used up all of his life force in the process, which cost him not just his muscles, but also life.
Uryu Ishida (Bleach) using Quincy: Letzt Stil to boost his strength, as the cost of his powers after the brief moment. The only way to recover was to shoot him 19mm to the right of his heart after exhausting him completely, thus the Quincy: Letzt Stil has been considered an obsolete technique.
Ichigo Kurosaki (Bleach) using the Saigo no Getsuga Tenshō: Mugetsu , allowing him to transcend the limits of both Shinigami and Hollow, but will deprive him of his power after use. He only recovered (and stronger than before) when Gotei 13 members transferred a bit of their own power each to him.
Sajin Komamura (Bleach) used his clan's Humanization Technique to temporarily regain his human form and the associated power boost and immortality, but this eventually regressed him to a mere wolf.
Goku (Dragon Ball) uses the x10 Super Saiyan Blue Kaioken to gain an explosive burst of power during his battle with Hit, enough that Hit's Time-Skip technique was rendered useless against him. However, as the technique was incomplete at the time, it only had a 10% success rate, and a 90% chance of immediate death; though he survived, his usage of the technique led Goku to develop Delayed Onset Ki Disorder, a medical condition that greatly reduced both his Ki control and capacity.
In the hopes of destroying Majin Buu, Vegeta (Dragon Ball) expended all of his life energy in the form of the Final Explosion, devastating the landscape and blowing Majin Buu to pieces. As a result, he was reduced to a stone statue and crumbled to dust.
Natsu Dragneel (Fairy Tail) has always been using more magic than his body can supply, leading to him to developing an Anti-Magic Tumor. He would have died from it, had the tumor not been shrunk down to a benign level.
Rasen (Flame of Recca) used the Kōkai Gyoku to erase Kagerō's immortality curse, but it was too much for the weapon to take that it self-destructed before it could take Rasen's existence as payment.
Might Guy (Naruto) opened all Eight Gates to gain power surpassing that of the Five Kage, but was destined to die from the strain. Even though Naruto saved his life, the recoil damage inflicted onto him forced him to retire from battle.
Mizuki (Naruto) drank a flawed potion that gave him an explosive boost of power, greatly enhancing his physical attributes, but the strain on his cells caused his body to breakdown shortly after, and he lost his ability to use ninjutsu ever again. Had Tsunade not saved him, he would have actually died.
After using the Convexity Fury to defeat and purify Dark Cynder, Spyro (The Legend of Spyro) lost all of his elemental powers, forcing him to relearn them with help from the Chronicler.
Superman (DC Comics) uses the Super Flare to expel all of the solar energy in his cells in the form of a massive explosion that incinerates everything within a quarter-mile radius, at the cost of him losing his powers for the next 24 hours.
The first time she activated her Household Vessel, Morgiana (Magi: The Labyrinth of Magic) gained a massive boost of power, but in the process, she burned through her body's supply of Magoi, leaving her near-death.
Hody Jones (One Piece) overdosed on Energy Steroids, which kept over-bursting his powers far beyond his body's limit, but eventually, he aged prematurely so much that he could barely stand up without a walking cane.
Toguro (Yu Yu Hakusho) raising his muscles to 100% of his 100% power, forcing past his limit. However, as he used his life force to do so, the strain caused his body to shatter upon defeat, and he died shortly after.
Lestion (Yumekui Merry) can kill any dream demon with his gun, but doing so will destroy him and shatter his vessels conscious and subconscious minds in the process.