With the aid of the Kaioken, Son Goku (Dragon Ball series) is able to increase his Ki reserves up to 20 times their natural limit, but at the cost of exhausting his body.
Whenever Master Roshi (Dragon Ball series) enters his MAX Power form, he gains a massive increase in power and muscle mass, allowing him to hold his own against strong opponents.
By facing his fears and controlling his heart, Krillin (Dragon Ball series) obtains the No Ego Zone state.
Beerus (Dragon Ball series) in his Angered State.
After becoming Super Saiyan Gods and adapting to its power, Goku and Vegeta (Dragon Ball series) became Saiyans beyond God, enabling them to use the Super Saiyan God power in their base forms.
After having all of his latent power unlocked by the Old Kai, Gohan (Dragon Ball series) obtained the Potential Unleashed form, his most powerful state of being.
Liqueur (Dragon Ball Super) entering his enhanced Nine-Tails form.
Using Namekian Fusion to merge with fellow Namekians Nail and Kami, Piccolo (Dragon Ball series) became a Super Namek, possessing power surpassing that of an untrained Super Saiyan.
Dabura (Dragon Ball series) uses Demonic Will to enter a powered-up state during his fight with Gohan.
After being corned by Goku in the final moments of the Tournament of Power, Jiren (Dragon Ball Super) became angered and awakened a deeper threshold of latent power, surpassing his previous full powered state, and achieving his Burning Ultimate Warrior state.
In his Wrath State, Broly (Dragon Ball Super: Broly) utilizes the power of the Great Ape, gaining its raw physical power and resilience without losing his speed.
The Future Warrior (Dragon Ball Xenoverse) is capable of utilizing both the Kaioken...
...and the Potential Unleashed form.
Rushuna Tendo (Grenadier) enters her Heightened State, providing an increase in strength, speed, and firepower.
Using Focus Spirit, Link (Hyrule Warriors) enters an enhanced state that increases his strength, speed, and defense.
Unable to wield armor like X, Zero (Mega Man X series) is able to posses the Black Zero enhancement, granting him an increase in attack powers, speed, and weapon energy.
Using the PED Suit and Phazon in her body, Samus Aran (Metroid) enters Hypermode, receiving a vast increase in firepower and strength.
When Liu Kang (Mortal Kombat: Shoalin Monks) executes his Brutality: Rage Mode, he enters a powered up state in which he covers himself in flames and becomes able to project powerful fireballs and pummel his opponents with fists of flames.
When Kung Lao (Mortal Kombat: Shoalin Monks) executes his Brutality: Razor's Edge, he enters a powered up state in which his Razor-Rimmed Hat becomes a deadly weapon in his hands, slashing his enemies multiple times before decapitating them.
Whenever he tapped into Kurama/Nine-Tails's chakra, Naruto Uzumaki (Naruto) was able to enter his initial Jinchūriki form, increasing his strength, speed, combat capabilities, and healing...
...and in his one-tailed state, he was shrouded in his Demon Fox Cloak which increased his abilities even further and granted him a degree of physical protection.
Tayuya (Naruto) using the second level of her Cursed Seal.
When he possessed the Cursed Seal of Heaven, Sasuke Uchiha (Naruto) received an increase in chakra and physical abilities....
...and at the seals' second level, he was able to fight on par with Naruto Uzumaki's One-Tailed form.
Users of the Eight Inner Gates such as Rock Lee, (Naruto) are able to open them in order to gain access to a great amounts of chakra at the cost of doing extreme damage to their body.
Using Gear Second to increase the flow of blood throughout his body, Monkey D. Luffy (One Piece) enters a state in which his strength and speed are greatly enhanced.
By releasing her limiter, Aigis (Persona 3) enters Orgia Mode, her most powerful state of being.
The Lost Galaxy Rangers (Power Rangers Lost Galaxy) can use the Lights of Orion to access a state in which they able to enhance the strength of most their arsenal and ultize their Power-Up Mode.
The Lost Galaxy Rangers can also use the Lights of Orion to empower their Galaxy Megazord and its saber.
Yang Xiao Long (RWBY) using her Semblance
to use the energy from every blow she takes to make herself more powerful, entering a state in which her strength is doubled.
Using Dark Gaia's power, Sonic the Werehog (Sonic Unleashed) enters Unleashed Mode, gaining enhanced strength, speed, and durability.
Whenever Shadow (Sonic the Hedgehog series) removes his Inhibitor Rings, he becomes Chaos Shadow, allowing him to tap into a limitless supply of Chaos Energy while draining his stamina.
Even with his Inhibitor Rings on, Shadow (Sonic the Hedgehog series) can enter an enhanced state of being via Chaos Boost.
Tsukune Aono (Rosario + Vampire) enhances his strength by releasing the first seal of his Holy Lock.
Those infected with the Hercules virus (Punch Line) can Uberfy, causing them to gain superhuman strength and speed.
Ryu (Ultimate Marvel vs. Capcom 3) uses Hado Kakusei to enhance his strength, speed, and techniques.