Esdeath (Akame ga Kill) is the strongest warrior of the Empire, it took the combined military might of one million men and ten Teigu users including Akame to finally defeat her.
Yachiru Unohana (Bleach) has mastered all the countless sword styles in the world, becoming the first Kenpachi.
Kenpachi Zaraki (Bleach) is one of the most powerful Shinigami to have ever lived. With his strength unleashed Kenpachi is able to slay Unohana, one of the strongest Shinigami of all time, with one blow.
Sosuke Aizen (Bleach) is one of the most powerful Shinigami in existence, the Wandenreich considered his power to be superior to Genryuusai.
Ichibē Hyōsube (Bleach) is one of the most powerful Shinigami and commander of the Royal Guard.
Yhwach (Bleach) is the most powerful Quincy that ever existed, defeating Genryusai Yamamoto without any effort at all.
Ichibē Hyōsube vs. Yhwach (Bleach)
Ichijo Aoi (Choujin Koukousei-tachi wa Isekai demo Yoyuu de Ikinuku you desu!) is the strongest martial art master in the world. She can single-handedly annhilate an entire army of terrorist using pure might and skill.
As an Angel, Whis (Dragon Ball Super) is a master of Ultra Instinct, and therefore a fighter stronger than even gods.
The Grand Priest (Dragon Ball Super) is the greatest fighter in all of existence. Even Whis admitted he would stand no chance against him.
Jiren (Dragon Ball Super) is the strongest mortal fighter in the multiverse. Having reached an unfathomable level of skill and power that surpasses even the Gods of Destruction.
Son Goku (Dragon Ball series), the first mortal to have mastered Ultra Instinct, putting him beyond even gods.
Acnologia (Fairy Tail) who is considered the King of Dragons possesses such ludicrous power that he is greater than the entire formidable armies of Alvarez and Ishgar and the mighty Wizard Saints and the dreaded Spriggan 12.
Having been a full fledged martial artist since the age of 3, Kenshirō Kasumi (Fist of the Blue Sky) wander the world crippling or killing those he would fight earning the moniker of Yánwáng (King of Death).
Kenshiro (Fist of the North Star) is ultimately regarded as the world's strongest man. His mastery of the greatest martial art the globe over, The Hokuto Shin Ken (Big Dipper God Fist), has garnered him titles such as the Savior of The Century's End.
Isaac Netero (Hunter × Hunter) is one of the strongest characters of the series and an extremely powerful practitioner of Nen.
Meliodas (Nanatsu no Taizai) In the past was considered to be one of the most callous of the Demon Clan and the former leader of the Ten Commandments. Feared by even the Goddess Clan for his monstrous power, combat and sword skills. Being considered the only one worthy of the position of Demon King.
Madara Uchiha (Naruto) was one of the most gifted shinobi in history. His tremendous skills in armed and unarmed combat allowed him to take an army of highly skilled shinobi at once.
Naruto Uzumaki and Sasuke Uchiha (Naruto) have surpassed their predecessors Hashirama and Madara as the most powerful Shinobi of all time.
Nagi Springfield (Negima) is considered as the strongest Magic Knight Magi not only for his magical prowess, but also monstrous battle strength. In just his teens defeated the Mage of Beginning, a powerful and Ancient Archmage feared as the greatest threat to the Magic World...
At the age of 10, Negi Springfield (UQ Holder) defeated his father's longtime rival Jack Rakan and destroyed demons of the Mage of Beginning and his father who was possessed by the same person. As an adult was known as the most powerful immortal mage able to move at the Speed of Lightning, while utilizing thousand different magics.
Jack Rakan (Negima) a powerful Gladiator with immense combat strength, magic and ki that borders on insanity, being the only person who could fight against his eternal rival, Nagi Springfield…
…his abilities earned him the titles 'Thousand Blades', 'Man Who Cannot Die', 'Immortal Fool, 'Human Atomic Bomb', 'Ultimate Hard Worker', and 'That Damn Guy Who You Can Stab With Swords All You Like And'... you get the point.
Dracule Mihawk (One Piece) is the Strongest swordsman in the World...
...His skills in swordsmanship are so immense to the point where he is able to overpowering even Roronoa Zoro with a mere dagger.
Before his death, Edward Newgate/Whtebeard (One Piece) held the title of the Strongest man in the World for his physical power, which is far superior to even a giant and having eaten the Gura Gura no Mi, the strongest Paramecia-type Devil Fruit, many calmed he had the power to destroy the world.
Charlotte Linlin/Big Mom (One Piece) is one of the world's most powerful pirates; even at the age of 5, she effortlessly defeated one of the Giants' greatest warriors.
Kaido (One Piece) is hailed as the strongest beast in the world.
Shinobu Sensui (Yu Yu Hakusho) mastered the Resshūken, fighting style that is only available to fighters that have mastered all other forms of martial arts. He also mastered the Sacred Energy, the highest echelon of power that even Genkai couldn't achieve.
Raizen (Yu Yu Hakusho) was a Mazoku, an immensely powerful demon warrior, that even starving himself for centuries and merely using his descendant, Yusuke Urameshi, as a temporary medium he was able to decimate the mighty Sensui.
Jin Toujou (Shinmai Maou no Testament) has supreme strength and fighting abilities among the Hero Tribe, so much so that during their war with the Demon Clan, the original Demon Lord pulled back his forces in fear of his monstrous strength; being of akin to a War God...
...during the climax of the Great War, Jin pushed both Sapphire
out of a dimension that they were all trapped in where a number of twenty Ancient Evil Dragons, Fafnir were located, one thing led to another, and Jin killed them by himself just as he was about to be saved.
Edelweiss (Rakudai Kishi no Cavalry) is the world's strongest swordsman and a Desperado, her combat skills greatly outmatched Ikki who was fighting at his best; even leaving him barely able to fight after their match concluded.
Hou Ken (Kingdom) is a Bushin, a path seeker of the martial path who "host a violent god" within himself....
...powerful fighter who is strong enough to kill multiple opponents with one slash...
...move as fast as the eye can see despite his large frame...
...he is also formidable without his glaive, having killed a tiger with bare hands.
Haimura Moroha (Seiken Tsukai no World Break) is the current incarnation of Kensei Flaga, who took on nations by himself using his unrivaled swordplay, combat prowess and tactical skills.
Kaguya Otsutsuki (Naruto) attained god-like power she used put an end to a war-torn era single-handedly and was worshiped as a goddess for her power.
Belzard (Highschool DxD) is the most powerful Red Dragon Emperor, having defeated two White Dragon Emperors in his lifetime.