In his Ultimate form, Ben 10,000 (Ben 10: Ultimate Alien) can instantly use any of his alien powers without changing form, as well as access Anodite magic.
Dante's (Devil May Cry) Majin Form is his true demon form, and his highest state of power.
After receiving the chakra of all nine Tailed Beasts, as well as half of the power of the Sage of the Six Paths, Naruto Uzumaki (Naruto) reached his highest state of power, Six Paths Sage Mode.
Kal Kent (DC Comics), an evolved Kryptonian from the year 1 million, possesses vastly evolved Kryptonian powers, as well as several others as a result of additional alien, extradimensional, and supernatural admixtures in his bloodline.
Astraea (Sora no Otoshimono) evolved to her absolute peak state after activating her Pandora System twice.
Godzilla from (Godzilla: Final Wars) is the most powerful incarnation after gaining infinite Kaiser power.
Evangeline (UQ Holder) has evolved past her original state of power after 80 extra years of being alive, allowing her to master Magia Erebea to a whole new level, granting her the power of Krystalline Basilea a state beyond Queen of Ice.
After defeating Akuma, Rugal Bernstein (King of Fighters/Capcom vs. SNK 2) took Akuma's Satsui no Hado
for himself and combined it with his Orochi power, becoming God Rugal.
Gon Freecss (Hunter X Hunter)
Sōsuke Aizen (Bleach) gained godlike power upon becoming one with the Hōgyoku, with his final form transcending the limits of Soul Reapers and Hollows alike.
When using the Final Getsuga Tensho, Ichigo Kurosaki (Bleach) fuses with Zangetsu and his inner Hollow, reaching his highest state of power.
After having the Mantra Reactor of the Karma Fortress implanted in his body, Asura (Asura's Wrath) obtained godlike power, becoming Asura the Destructor.
White Raven (Teen Titans) is Raven's most primal, significant, and powerful form, mostly shown as a symbol of her highest hidden power and her inner purity against the consuming evil of her father Trigon.
In the Avatar State, Avatars such as Aang (Avatar: The Last Airbender/The Legend of Korra) are at their most powerful, enabling them to channel vast cosmic energies and the knowledge and spirits of all past Avatars.
Upon obtaining all of the lost fragments of Soul Edge and rejoining them, Nightmare (Soul Calibur) becomes Night Terror, possessing amplified powers and the ability to fly.
Medaka Kurokami (Medaka Box) has reached her highest state of power, End God Mode.
After receiving energy from all of the Spirits, Tohka (Date A Live: Mayuri Judgement) achieves her ultimate form, Full-Form Astral Dress: Twin Blades Mode.
Mega Man X (Mega Man X) is at his highest level of power when he wears the Ultimate Armor.
Pegasus Seyia (Saint Seyia) is wearing a God Cloth, a Bronze Cloth reborn from Athena's blood, and above nearly all other Cloth types, inferior only to the Kamuis of the Olympian Gods.
Sora's Final Form (Kingdom Hearts) represents his highest level of power, allowing him to use all of his abilities and the Keyblade to their fullest extent.
Saitama (One-Punch Man), after breaking his physical limits, has shown immense strength that has remained unparalleled by anyone.
Galand (Nanatsu no Taizai) when he activates his ability Critical Over augments his physical power to it's absolute limits until his magic power runs out.
After being revived and undergoing intense training for the past four months, Frieza (Dragon Ball) achieves the Golden Form or Ultimate Evolution, the strongest transformation of his race which amplifies his power to the utmost limit.
After eating the final phantom ingredient, CENTER, Acacia (Toriko) achieved his ultimate form which would allow him to consume NEO and become unstoppable.
All of the Mixel tribes mix together with a Rainbow Cubit that creates the biggest max of all, The Ultra-Miximum Max (Lego Mixels).
Wise Oracle (Valkyrie Crusade) is Oracle at her maximum stage of power.