Monkey D. Luffy is the protagonist of One Piece who sets out to sea to become the Pirate King by claiming the grand treasure known as the One Piece. Early into the story, Luffy establishes the Straw Hat Pirates and manages to conquer the entirety of the East Blue and later on, the Grand Line as well.
Currently, he is one of the Four Emperors of the Sea and to get here, he has had to fight several powerful enemies and crush them into the dirt. While all of Luffy's victories are enjoyable for the fans, only a handful can be considered to be the very best in One Piece.
8 Defeating Moria
Luffy's fight against Moria might not be the flashiest seen in One Piece, however, it is one of the most important clashes that he has engaged in so far on his journey. Against Moria, Luffy's never say die attitude was highlighted at its very best. Fans also saw the Straw Hat Pirates put their trust in their captain as he sprung forth to save the day.
This fight was incredibly difficult for him as he had to take down the giant zombie oars first. After defeating Oars, Luffy took it upon himself to engage Gecko Moria in combat and put an end to his tyranny in the Florian Triangle as well.
7 Defeating Doflamingo
Luffy clashed against Doflamingo in the Dressrosa arc of One Piece. This arc is one of the very best in the story and it sees the former Celestial Dragon, Doflamingo, engage in combat with both Luffy and Law. While Law has a history with Doflamingo, it is Luffy who he entrusts with his burden and, from there onwards, the Straw Hat Pirate takes it upon himself to crush Doflamingo.
During this fight, fans get a good taste of what the pirates in New World are made of. At the same time, Luffy's training during the 2-year timeskip bears fruit as he enters a new transformation called Gear Fourth. The fight also delivers incredible action which is topped off by an extremely overpowered technique that Luffy uses to crush Doflamingo called King Kong gun.
6 Defeating Arlong
Lucy's fight against Arlong takes place relatively early in the series, however, it bears tremendous significance both for Luffy and the character of Nami as well. After his navigator asks him for help, Luffy marches to Arlong Park and crushes the Fish Man with his bare fists. While this fight is certainly not the best when it comes to action, the emotional weight that it carries is possibly one of the greatest in the story.
This fight encapsulates what One Piece is all about and sums up the character of Luffy in a short yet simple manner. Undoubtedly, it is one of the very best fights in the story to date.
5 Defeating Enel
Luffy fought against Enel, the God of Skypiea, during the Sky Island arc of One Piece. Enel was an incredibly powerful adversary for Luffy to face, especially due to the powers of his invincible Logia Devil Fruit called the Goro Goro no Mi. However, as fate would have it, Luffy was his perfect counter.
This fight showed fans how Luffy was always meant to be God's natural enemy and gave them an idea of what his character is all about, especially when it comes to tackling the ideas of freedom and fate. Luffy absolutely crushed Enel and in doing so, saved Skypiea from utter destruction.
4 Defeating Katakuri
Lucy's fight against Katakuri is one of the very best in the story when it comes to action. This fight took place in the Whole Cake Island arc and saw Luffy come face to face with an enemy that was much stronger than him. During this fight, Luffy tries to evolve mid-combat and that is, essentially, what makes it so special.
Katakuri paints an image of a better version of Luffy and the Straw Hat pirate has to do everything in his power to defeat him. This fight sees Luffy advance his Haki to the very next level and, at the same time, also showcase his timeskip training by delivering yet another ferocious form of Gear Fourth, called Snakeman.
3 Defeating Crocodile
Luffy's fight against Crocodile will always be special to the fans as it was the very first fight that he took part in and where he felt out of his depth. Luffy lost to Crocodile twice and that aspect of this fight makes it very special.
Furthermore, the weight it carried on an emotional level was completely different from the vast majority of the fights that fans saw before it. Crocodile eventually fell while Luffy was carrying the weight of Arabasta on his shoulders and for that reason, this fight certainly remains special to this day.
2 Defeating Lucci
Luffy fought Lucci during the Enies Lobby arc to save his friend, Nico Robin. To rescue his friends, Luffy will go to any length and this fight encapsulates that part of his character very well. Even though Luffy hit his limit several times during this fight, he managed to push beyond it simply to save his crewmate.
All that, when combined with the fact that this fight is topped with incredible action as well as tension makes it one of the very best fights in One Piece. The fact that Luffy was able to defeat Lucci makes it one of his very best victories so far and some would argue that it is his best.
1 Defeating Kaido
Kaido is certainly the biggest adversary that Luffy has faced so far on his journey as a pirate. Being an Emperor of the Sea, Kaido is among the strongest characters in the entire world of One Piece, if not the strongest. To defeat him, Luffy had to face defeat several times and grow while fighting. This fight saw Luffy take his first step as an Emperor level pirate and from there onwards, embrace the idea of freedom to the fullest.
Luffy Awakened his Devil Fruit and became Nika and in doing so, he spread joy and laughter to the land of Wano. He carried Wano's weight on his shoulders and liberated the country from 20 years of oppression. This victory over Kaido is, by far, the most special one that Luffy has enjoyed so far.