"Individually, they can take down any bender. Put them all together, they could take down the entire world."
― Zuko (Avatar: The Legend of Korra); talking about the Red Lotus
"The great war ended with neither winners or losers due to Acnologia's existence, as if mocking the deaths of all those who died in the war, victory was his and his alone."
― Irene Belserion (Fairy Tail)
"I know in my heart that it was impossible but, for that entire fleet of 5,000 pirates to be completely eradicated by a single man!"
― Gin (One Piece)
"You're not a soldier." "Damn right I'm not - I'm an army."
― James Rhodes and Tony Stark/Iron Man (Marvel Cinematic Universe)
"Ten stormtroopers, a hundred, a thousand—the numbers don't matter."
― Galen Marek/Starkiller (Star Wars: The Force Unleashed)
"Three hours, Avengers. That's how long it took him to murder every man, woman, and child in Slorenia. Three hours."
― Major Uto Smith on Ultron (Avengers 1998 20#)
"Devil King Clans? Devil King Army? You bastards should know I do not fear even that, you are free to gather all of your forces together to come after me, I will just slaughter them all, drown every last of you in a sea of your own blood!!"
The user is able to fight against seemingly, overwhelming odds with ease. They are a capable warrior on the battlefield, decimating the enemy single-handedly and with a near-supernatural finesse that pars with the skill of more experienced fighters. This ability can manifest in various ways but is usually the result of extreme martial skill. Users of this ability are as deadly at long-range combat as they are in close quarters.
If users are Immortal (may be part of this power anyway) then they themselves are an army killing machine with no end.
Last Stand Empowerment: The ability to spontaneously manifest the above power in suicidal situations. Almost always results in the user's death, though not before amassing a significant body count. Users who do survive its use may develop the permanent version.
Inverse Ninja Law: The ability to become more powerful as the odds are stacked against you. However, the opposite is also true. This may be exploited by genre-savvy opponents. Not necessarily unique to ninjas, see here for more details.
Asterix, and Obelix (The Adventures of Asterix) are capable of beating entire armies.
King Bumi (Avatar: The Last Airbender) took back Omashu and kicked out the Fire Nation (for good) by himself in a mere eight minutes during the eclipse.
Iroh (Avatar: The Last Airbender)
Heatblast (Ben 10) is capable of single-handedly defeating an army of Vilgax's basic drones.
Way Big (Ben 10) is one of Ben's most powerful transformations as shown when he defeated Vilgax along with his army in his first appearance.
Meg and Chris Griffin (Family Guy) were each able to kill a large number of students who attempted to kill them, turning the cafeteria into a genocidal scene.
While Kal-EL/Clark Kent/Superman (DC Comics) has been described as 'faster than a speeding bullet', 'more powerful than a locomotive' and being 'able to leap tall buildings in a single bound', these are not his greatest feats. When he is under the sun, his power increases exponentially, allowing him to defeat incredibly powerful opponents.
Bruce Wayne/Batman (DC Comics) is well known for using his intelligence, gadget expertise, detective skills, athletic prowess, and a strong force of will to overcome an army of foes and even super-powered beings...
Buddy Blank (DC Comics) truly lives up to his codename of OMAC (One Man Army Corps).
Superboy Prime (DC Comics)
The Martian Manhunter vs. The Justice League (DC Comics: New 52 )
Slade Wilson/Deathstroke (DC Comics)
The Incredible Hulk (Marvel) is one of the most powerful beings in his respective universe. His ever-growing rage is able to increase his power to the point where he is strong enough to match the strength of beings such as Thor, Silver Surfer, and the Sentry.
Ares, the God of War (Marvel Comics) the original one-man army…
Steve Rogers/Captain America (Marvel Comics) can easily hold his own against a legion of Hydra operatives…
…SS troops back in WWII…
Multiple Man (Marvel Comics) is literally a one-man army.
Matt Murdock/Daredevil (Marvel Comics) is capable of fighting large groups of Ninja…
…and Yakuza gangs...
As a highly skilled master assassin and mercenary, Wade Wilson/Deadpool (Marvel Comics) is capable of fighting multiple opponents while (of course) talking.
After being modified into a cyborg by the Weapon X program, Garrison Kane (Marvel Comics) became a walking arsenal.
Sometimes pushing his healing factor to its limit, James "Logan" Howlett/Wolverine (Marvel Comics) is capable of taking on multiple opponents…
…Savage Land Cavemen…
…and while under the influence of mind control, S.H.I.E.L.D.
Taskmaster (Marvel Comics)
With his expertise in weaponry, combat skills, and armed with his magic sword, Jack (Samurai Jack)...
...is able to take on giant monsters,...
...hundreds of robot destroyer drones,...
...and even face off against Aku himself.
Tai Lung (Kung Fu Panda) tearing the elite Anvil of Heaven rhino guards.
The Anti-Monitor (DC Comics)
Lance Sterling (Spies in Disguise)
Classified as a Class Omega threat, Nimrod (Marvel Comics) contains have a wide range of applications needed to fight, kill, or harm superhumans.
Blue Falcon (Hanna-Barbera/Mystery Incorporated) taking on an army of Destroido Guards.
An incredibly talented swordsman, Afro (Afro Samurai) is strong enough to cut through multiple thugs and warriors quickly and effortlessly.
Due to his proficiency with ATs, Agito (Air Gear) can single-handedly defeat and kill many adversaries.
Esdeath (Akame Ga Kill) is hailed as the strongest warrior of the Empire, able to fight entire an army of one million soldiers and 10 Teigu users by herself.
The First Shinigami Captains (Bleach) were noted to be the strongest generation of Shinigami warriors in the history of the Gotei 13…
…including Genryusai Yamamoto who was hailed as the strongest Shinigami for over 10 millennia…
…and Yachiru Unohana, the bloodthirsty master swordswoman who mastered eight thousand schools of swordmanship.
The Vizards (Bleach) are highly skilled and experienced fighters being former Shinigami Captains and Lieutenants, and with their hollow powers they can annihilate armies of Gillians.
Sosuke Aizen (Bleach) is one of the most powerful Shinigami ever known, able to singlehandedly defeating multiple Shinigami Captains and Vizards without using his full strength.
After 300 hundred years of endless combat, its just another day for Zodd the Immortal (Berserk).
Earning the title, Hundred Man Slayer, Guts (Berserk) became infamous for slaying over 100 Tudor mercenaries during the 100 Year War…
…and since becoming the Black Swordsman and being branded by the God Hand has killed over a thousand evil spirits, Apostles and their spawn.
Papillon (Buso Renkin) turned into a deadly fighter once becoming a humanoid homunculus, having devoured his household's entire security staff and defeated the likes of his more experienced great-great grandfather Dr. Butterfly and the seasoned warrior Genji Ikusabe.
Ichijou Aoi (Choujin Koukousei-tachi wa Isekai demo Yoyuu de Ikinuku you desu!) is the strongest martial arts master in the world, able to destroy an entire terrorist organization by herself.
Rei Ogami (Code:Breaker) was able to kill entire armies of hoodlums, yakuza, corrupt policemen, and military-trained personnel with his blue flame.
Toki (Code:Breaker) obliterating an army of military-trained guards with his magnetism, easily deflecting their bullets back at them…
…or by using his deadly marksmanship to snipe them down at tremendous precision and distance.
Denji (Chainsaw Man)
Kurumi Tokisaki (Date A Live) is an immensely powerful S-Class Spirit being capable singlehandedly wiping out an army of DEM Wizards and Bandersnatch robots.
As a child, Son Goku (Dragon Ball series) single-handedly defeated and destroyed the Red Ribbon Army and ever since then, he has increased in both strength and power. His martial art skills, ki abilities, and various transformations allow him to overcome the strongest of opponents throughout his life.
Much like his rival, Vegeta (Dragon Ball series) is a very powerful Saiyan warrior. His energy based attacks, physical techniques, and Super Saiyans transformations have allowed to defeated countless enemies.
In his mastered Golden Form, Frieza (Dragon Ball Super) single handedly defeated an entire army of assassins within a few minutes. Even one that was empowered by a God of Destruction.
In her Berserker form, Kale (Dragon Ball Super) started overpowering most of the fighters in the Tournament of Power, inclduing Super Saiyan Blue Goku, and even scored a few defeats in succession.
Natsu Dragneel (Fairy Tail) is a top class Fairy Tail member and the strongest demon from the Book of Zeref, his strength is so insane he can take down over 900 highly trained soldiers with just one breath attack.
Erza "Titania" Scarlet (Fairy Tail) has defeated over 100 high-level monsters in a row, which was considered impossible, even for the best.
Acnologia (Fairy Tail) the King of Dragons possess 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
After years of training, Kenshiro (Fist of the North Star) can easily kill several humans without taking a single hit...
...single-handley destroy various armies of the Land of Asura...
Devil Rebirth (Fist of the North Star) killed 700 people with one use of his "Rakan Niō Ken" (Arhat Deva Fist).
A powerful human Homunculi, King Bradley (Fullmetal Alchemist series) possessed inhuman skill in swordsmanship that allow him dispatch countless soldiers as if it were a mere sport.
Hattori Zenzō (Gintama) single-handedly taking down the entire Kiheitai fleet with his immense ninja techniques alone.
Utsuro (Gintama) single-handedly slaughtered a majority of the Shinsengumi and Harusame's 7th Division of Yato members.
Hailed as the Strongest Human, Cao Cao (Highschool DxD) is a powerful fighter and the wielder of the True Longinus, being able to fight the most powerful supernatural beings.
Vali Lucifer (Highschool DxD) is descendant of Satan Lucifer and the wielder of the Divine Dividing, Azazel stated Vali is the most powerful White Dragon Emperor to have ever existed.
Issei Hyodou (Highschool DxD) is the wielder of the Longinus Boosted Gear, through constant intense training Issei became a extremely powerful fighter, able to fight the most powerful supernatural beings from a Super Devil to a Evil God and even one of the strongest Evil Dragon.
Dulio Gesulado (Highschool DxD) is the wielder of the Longinus Zenith Tempest and Strongest Exorcist of the Church.
Sairaorg Bael (Highschool DxD) is wielder of the Longinus Regulus Nemea and a extremely powerful martial art master.
Hayato Furinji (History’s Mightiest Disciple Kenichi) is the ultimate one-man army, able to take on an entire military base all by himself, as well as use humans like shurikens and strong enough to destroy tanks by himself, all while fighting with his eyes closed and only using 0.0002% of his full power.
The Band of Seven (InuYasha) was a group of mercenaries that savagely slaughtered entire armies. Even one of them was capable of grave destruction, but together they could “do the work of a hundred men.
Armed with masterful swordmanship and a powerful weapons expert, Ri Shin (Kingdom) is fully capable of taking on multiple opponents with his martial prowess alone as he displays it with his King's Sword's swordsmanship while killing multiple Wei soldiers...
...and decimates an entire Zhao battalion with his podao.
Yo Tan Wa, the King of Death (Kingdom)
Kyou Kai (Kingdom)
A powerful man of immense strength, Mou Bu (Kingdom) displays his brutal strength on the battlefield as he smashes through multiple heavily armored soldiers just by swinging his war mace.
Rin Ko of the Four Heavenly Kings (Kingdom)
Ou Hon (Kingdom)
Earl Shi of the Wei Fire Dragons (Kingdom)
Shi Ryou (Kingdom)
Sho Fukamachi/Guyver I (Guyver)
Sun Seto (My Bride is a Mermaid) is skilled in swordplay to the extent that she was able to take on and defeat a rival yakuza gang by herself.
During the final days of the Third Great Shinobi War, Minato Namikaze (Naruto) became famous for killing over 100 shinobi earning the title the Yellow Flash. If he was so much as spotted anywhere near the battlefields, the enemy would sound the retreat.
Sasori of the Red Sand (Naruto) was a powerful puppeteer shinobi and a cunning one at that, his supreme skill in Puppet Mastery allowed him to assassinate the Third Kazekage and destroy an entire nation.
The Six Paths of Pain (Naruto) were known for the entire destruction of the Hidden Rain and Hidden Leaf Villages.
Third Raikage Ay/A (Naruto) was able to singlehandedly fight off 10,000 Iwagakure shinobi for three days and three nights nonstop before finally succumbing to death.
Sasuke Uchiha (Naruto) is an extraordinarily skilled swordsman, able to slay an army of skilled Samurai with ease.
Madara Uchiha (Naruto) annihilate half of the relatively undamaged Fourth Division seconds after being resurrected and was strong enough to defeat the 5 Great Kages.
Even at the age of 14, Obito Uchiha (Naruto) was able to slaughter an army of the Bloody Mist ANBU ninja…
…and after sealing the Ten-Tails into his body becoming its Jinchuriki, he could take the entire Allied Shinobi forces and overpower them.
Admiral Kizaru (One Piece) single-handedly captured 500 pirates during his raid on Sabaody Archipelago.
The Blackbeard Pirates (One Piece) are extremely powerful fighters, each member capable of decimating entire countries…
Edward Newgate/Whitebeard (One Piece)
…and particularly their leader Marshall D. Teach, possessing powers of both Yami Yami no Mi and Gura Gura no Mi Devil Fruits, the most powerful fruits for both Logia and Parameica class.
During his final day as a pirate, Kuro (One Piece) killed an entire ship full of trained Marines with his immense speed.
As a combatant for the Big Mom Pirates, Randolph (One Piece) is perfectly capable of wiping out entire armies.
Demon Lady, Charlotte Amande (One Piece) is a powerful master swordswoman…
…capable of massacring an entire army of armored knights single-handedly.
Rob Lucci (One Piece) is a genius Rokushiki master hailed as the strongest assassin of his generation. Even at the age of thirteen, he killed over 500 soldiers and an entire crew of pirates by himself.
Vinsmoke Judge (One Piece) is the supreme commander of the Germa 66 and is an immensely powerful warrior in his own right.
Refereed as the Monster Trio, Monkey D. Luffy, Roronoa Zoro, and Vinsmoke Sanji (One Piece) are three of the strongest members of the Straw Hat Pirates. Capable of defeating entire armies of pirates, marines, giant monsters, and the most powerful enemies of the New World.
After two years of extensive training, Usopp, Nami, Chopper, Nico Robin, Franky, and Brook (One Piece) became highly skilled and formidable fighters able to defeat large numbers of powerful enemies in the New World.
Charlotte Perospero, Compote, Katakuri, Smoothie, Daifuku & Oven (One Piece) are the strongest members of the Big Mom Pirates, their strength is described as monstrous even among a Yonko Pirate Crew.
Saitama (One-Punch Man)
Lu Bu (Record of Ragnarok)
Thor (Record of Ragnarok)
Kenshin Hiruma (Rurouni Kenshin), the Battosai/Man Slayer can dispatch several opponents with little effort while only using his sheath.
Honoka (The Third) once destroyed an entire army all by herself with just a single swing of her sword.
Saito Hiraga (Zero no Tsukaima) is the current incarnation of Gandalfr: The Left Hand of God. Being Gandalfr grants him incredible physical capabilities and innate mastery of all weapons, allowing him to single-handed fought an army of 70,000.
Personal IS pilots (Infinite Stratos) have been military trained in using the IS to it full potential, giving them comparable strength to a country's military. Tatenashi Sarashiki has displayed her ability to easily handle other personal IS pilots.
The result of hellish Iwagakure ninja training, Gabimaru the Hollow (Hell’s Paradise: Jigokuraku) is a walking army...
..., showcasing his skills as he killed over 20 samurai police officers during his capture...
As he continues to improve himself after his Double Awakening, Sung Jin-Woo (Solo Leveling) can easily fight with the strength of over 100.
The Seven Dragon Paladins (Undefeated Bahamut Chronicle) are the strongest Drag-Knights from their respective countries, each capable of overpowering entire armies of monsters on their own.
Although being a slime, Rimuru (That Time I Got Reincarnated As a Slime) is a powerhouse in his own right.
...Examples like him defeating 5 Ogres By Himself...
...Killing the Orc Lord and absorbing his powers
...And Killing 10 Thousand soldiers out of anger for killing many of his friends and residents
Bruce Wayne/Batman (Arkham Series) is an extraordinary martial art master, able to fight single-handedly the most dangerous criminals and crime syndicates of Gotham Underworld.
Asura (Asura's Wrath) possesses speed, strength, durability, and stamina far beyond anything one could call human. The greatest assets to his abilities: his Mantra affinity, Wrath, allows him to increase his power to the point where he able to destroy entire fleets, The Gohma: Vlitra, and even Chakravartin The Creator himself.
The Doom Slayer (Doom) can single-handedly defeat legions composed of the strongest demons of Hell.
The Dovahkiin (Elder Scrolls) is a godly powerful mortal, and can single-handedly turn the tide of Skyrim's Civil War.
Some SOLDIERs (Final Fantasy 7) are capable of taking on the battlefield alone.
Kratos (God of War series) is one of the best examples of this ability. He has shown impressive feats of strength and magic in order to defeat hundreds of foes, deities, and even the mighty Zeus.
Gordon Freeman (Half-Life Series) is capable of defeating hundreds of US Marines, Overwatch Soldiers, and Synths on his own.
Even amongst his fellow Spartan-II Super soldiers, John-117 (Halo) is capable of defeating legions of enemy soldiers.
As shown multiple times in his life, Jak (Jak and Daxter series) has proven to be a very capable fighter. Thanks to his ability to channel various forms of Eco, melee skills, and acrobatics, he has defeated ambushes of Lurkers, Crimson Guards, Metal Heads, and Dark Makers.
Sora (Kingdom Hearts) can handle an entire army of 1000 Heartless with little effort.
Possessing speed, strength, endurance, his traditional X-buster, and his limitless potential, X (Mega Man X series) is capable of taking on numerous Mavericks, Mechaniloids, and even Sigma however strong they may be.
As shown in the past, present and future, Zero (Mega Man X, Zero, and ZX series) have shown to be strong enough to take on an army of Mavericks single-highhandedly.
Big Boss (Metal Gear) is renowned as the greatest soldier of the 20th century.
Samus Aran (Metroid) has fought the massive legions of the Space Pirates for years.
Ryu Hayabusa (Ninja Gaiden) is the Ultimate Ninja. As the Dragon Ninja of Hayabusa Clan, Ryu's master-level skills of hand to hand combat, Ninpo and weaponry, especially with his Dragon Sword, has allowed him to overwhelm and defeat enemy ninja, soldiers, robots, cyborgs, mutants, monsters, Fiends, and even supreme deities such as the Greater Fiends and Archfiends
As The Fastest Thing Alive, Sonic (Sonic The Hedgehog) is well known for using his speed while in ball form to combat hundreds of Dr. Eggman's robots as his speed in his ball form is strong enough to break or cut through their metallic armor. Outside of his speed, he possesses great physical combat skills despite having little to no training in martial arts as seen when he faced off against the Gizoid, Emerl, who possessed all of the abilities of him and his allies.
Nightmare (Soul series) has been known to be a scourge on the battlefield, able to vanquish entire armies with his demonic sword Soul Edge.
Agent 3 (Splatoon) can singlehandedly defeat entire armies of Octarians and the five Great Octoweapons.
Strider Hiryu (Strider series) is a high-tech mercenary of the highest caliber. His skills in martial arts, agility, speed, trick tools, and his Falchion have allowed him to defeat robots, dinosaurs, warships, and even Grandmaster Meio.
Heihachi Mashima (Tekken) was a supreme martial art master, able to take down the majority of the technologically advanced Tekken Force army by pure might and skill.
By carrying the Spirit of the Hero, armed with his Master Sword and Hylian Shield, bearing the Triforce of Courage and mastery and possession of multiple weapons, gadgets, and magical items, Link (The Legend of Zelda series) is able to overcome countless forces of evil such as monsters, demons, the undead, and even Ganondorf.
Snow Demon (Valkyrie Crusade) is known as the One-Demon Army.
Kazuma Kiryuu (Yakuza) is an extraordinary martial art master, able to fight off entire gangs of Yakuza and overwhelm extremely strong fighters such as Majima and Taiga.
The Four Horsemen of Apocalypse (Darksiders) are supreme Nephalem warriors with tremendous supernatural powers, able to single-handedly slayed entire legions of fiendish demons.