One piece is one of longest-running anime's to date, recently celebrating its 20th anniversary. In 20 years, Monkey D. Luffy has had countless memorable fights against the toughest opponents.

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Traveling with his crew, the Straw Hat Pirates, they have crossed paths with many other pirate crews and the Marines. With every encounter, Luffy knows who he has to take down for his crew to win. With so many great fights spread over two decades, ranking all of them is a tall task, but in this article, we'll break down the top ten.

10 Luffy VS. Arlong

Arlong Laughing At Nami

Luffy taking down Arlong is so satisfying. The Arlong Park arc does a great job at building Arlong up to be this terrible Fishman. Through Nami's flashbacks, the anticipation for Luffy going after him is huge. The hype is at is highest after Luffy gives Nami her hat after she asks for help, and the Straw Hat Pirates take the famous walk to Arlong Park.

The fight moves into Nami's room, with Luffy destroying her childhood trauma before our eyes. He rains down a final Gum-Gum Battle-axe, taking down Arlong and the place that held Nami emotionally captive most of her life.

9 Luffy VS. Enel

Enel during One Piece's Skypiea arc

Enel is insanely powerful and unlucky that fate pitted him against Luffy, his living counter. Enel's lightning fruit being so powerful, and with his mantra, he proclaimed himself a god and ruled over all of Skypiea. Enel's "mantra"  turned out to be our first look at Observational Haki, which isn't even mentioned until hundreds of episodes after this arc.

Considering that, Enel was ahead of his time. Though with Luffy's rubber and battle adaptiveness, he was the perfect matchup to take down Enel.

8 Luffy VS. Crocodile

A close-up of Crocodile from One Piece, who has a groaning expression

Luffy facing Crocodile was a humbling experience. Crocodile was the second Logia type user Luffy had come into contact with and the first of the Seven Warlords. With escape not being an option like his first encounter against Smoker, Luffy is forced to overcome his inability to hit Crocodile. His first bout with Crocodile ends in his defeat.

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This fight serves as an essential progression for Luffy, overcoming this mounting obstacle that he is bound to face again in the future. With his cleverness, he figures out using water will help him make contact. With the fight going on amidst a civil war consuming Alabasta, a resounding finale concludes under the city, with Luffy punching Crocodile through the bedrock for the triumphant victory.

7 Luffy VS. Moria

Moria is the captain of the giant Island ship Thriller Bark, and the second Warlord to cross paths with Luffy. While maybe not being as fundamentally strong as Crocodile, with ample setup time and resources, Moria is worthy of his warlord title.

These circumstances play out perfectly for Moria when Luffy and crew land on Thriller Bark. Luffy's shadow is stolen and put into the giant Oz's corpse, essentially making a huge version of himself. Luffy leads the charge against the giant opponent, who ends up being perfect for the entire Straw Hat crew to fight together. Once they take Oz out, Luffy exposes Moria's inept one-on-one fighting ability, ultimately bringing him down.

6 The battle of Sabaody Archipelago

Luffy Left Saddened By His Crew Disappearing

The Sabaody Archipelago is the last stop before the new world. While not ranked number one, this may be the most important fight for Luffy, and it was a complete and utter defeat. All the chaos starts when Luffy delivers one of the best one-punch knockouts in the series to the Celestial Dragon Saint Charloss. This news spreads quickly and the Marines charge with the pending reinforcement of an admiral on the way.

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The fight starts with fans getting our first view of the other supernovas when Luffy, Kid, and Law start beating up on hordes of Marines. Things take a sudden turn when the "Kumas," later know as Pacifistas, start showing up. Luffy leads the Straw Hat Pirates in defeating one but is then overrun with the emergence of Sentomaru, another Pacifista, Admiral Kizaru, and the actual Kuma. Luffy watches in dismay as Kuma takes out the Straw Hats one by one. This defeat serves as a turning point in Luffy's realization of the gap in power that remains.

5 The Battle of Marineford

Whitebeard One Piece

Like the last entry, this fight isn't against a singular opponent, but it is too important to leave off the list. Luffy pours everything he has into this battle in an attempt to save his brother, Ace. Fighting alongside the Whitebeard pirates, Luffy charges through an endless amount of marines.

Luffy even briefly crosses paths with big names such as Mihawk, his Grandfather Garp, Sengoku, and the three admirals. The biggest moment for Luffy, though, is when he uses his Conqueror's Haki, knocking out countless marines and getting the attention of everyone on the battlefield. Sadly enough, the battle does not end well for Luffy and serves as the foundation in his determination to never lose anyone again.

4 Luffy VS. Hody

Hody monster

This entry's high rank has nothing to do with Hody but is mainly due to Luffy and his progression. This fight marks the first time viewers get to see the results of Luffy's training with Rayleigh during the two year gap. Luffy's entrance to the fight sets the tone when he is thrown up by a shark, disappears before Hody's eyes, and kicks him into a cliffside. Before he goes back in for more, Luffy uses his Conqueror's Haki and knocks out fifty thousand new fish-man pirates. Yeah, fifty thousand.

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This whole fight feels like the author Oda showing off Luffy, and it couldn't be better. Hody only stays in the fight thanks to the use of handfuls of energy steroids and getting the fight into the water. Even with the drug strength and water advantage, Luffy unleashes his Red Hawk, the cultivation of his training and inheritance of his brother's will. Shortly after, Luffy deals the finishing blow, another new move, the Elephant Gatling Gun.

3 Luffy VS. Lucci

Rob Lucci and Hatori from One Piece

Airing in 2007, this fight is still one of the greatest in One Piece. Lucci is the leader of the secret World Government unit CP9, who has taken Robin. By this point, Lucci is by far Luffy's greatest opponent, pushing the Straw Hat captain further than anyone ever had.

Luffy relies heavily on his newest technique, Gear Second, and reveals another new technique, Gear Third. Even with these two advancements, Lucci manages to pull ahead and deal a decisive blow, dropping Luffy to the floor. After a riveting speech from Usopp, Luffy gets back up but receivers another heart-wrenching blow.

Only this time, Luffy does not go down and unleashes everything he has into his strongest technique at the time, Jet Gatling Gun. Lucci is pummeled and goes down in one of the most compelling finishes to a fight the series has to offer.

2 Luffy VS. Doflamingo

Luffy VS Doflamingo

Doflamingo is one of the best villains introduced in One Piece so far. He is a ruthless agent of chaos who tramples on the lives of the inhabitants of Dressrosa. Doflamingo rules over Dressrosa like a puppeteer controls puppets. Luffy and Law fight together initially, but once Law is brutally wounded, only Luffy is left standing.

Facing his greatest opponent following the two-year gap, Luffy unveils the height of his training, Gear Fourth. With a completely changed appearance, Luffy goes all out and stuns Doflamingo with the extent of this ability. Even still, Doflamingo lived up to the reputation that had been built for him throughout the series, providing the first glimpse at a devil fruit awakening power.

1 Luffy VS. Katakuri

Luffy Using Gear 4th: Snake Man On Katakuri

This was the most anticipated fight in One Piece in a long time, and it completed surpassed expectations. The man with the bounty of 1 billion berries, Katakuri, represents the widest strength gap Luffy has ever overcome in a fight.

Being pushed into a corner, Luffy's only option is to learn Katakuri's Observational Haki ability as it is used against him. After some outside interference, Luffy is gravely wounded but Katakuri's honor brings him to wound himself in the same manner as to not have a dishonorable victory. After an epic clash of Conqueror's Haki, Luffy reveals a new Gear Fourth form called Snake Man, allowing him to just barely secure the victory.

NEXT: One Piece: Top 10 Monkey D Luffy Attacks, Ranked