Buggy is the main antagonist of the Orange Town Arc.Through his crazy streaks of good fortune, coupled with weaselly actions and lying, he has managed to gain power and favor with people by doing next to nothing. Oftentimes, happenstance makes him look more impressive and intimidating than he really is.
Buggy is one of the few villains to become reformed after facing Luffy, though only slightly. He also begins to accept people’s kindness, though he can still be cruel to anyone who is not a member of his crew or is aiding him in his goals.
Arlong is the main antagonist of the Arlong Park arc. He considers humans to be inferior beings, and is very cruel to them. He thinks nothing of killing a town full of humans, although he seems to prefer controlling people with money and deals (like Nami and Nezumi).
Crocodile is the main antagonist of the Alabasta Saga. He is self-assured, confident in himself and in his abilities. He has shown a complete lack of fear and doubt. He usually appears to be very composed, even when facing fearsome opponents like Whitebeard, Dracule Mihawk, and Akainu.
Crocodile has been shown to almost completely lack any code of honor. He also shows no emotional concern for any of his subordinates.
Rob Lucci is the main antagonist of the Water 7 Arc. He comes off as a cold and collected CP9 agent, almost never displaying any emotions.
In combat, he is a very sadistic and violent fighter, and also seems to derive amusement and gratification from inflicting physical and emotional pain on others.
He finds it offensive when someone shows weakness around him. The reason that he killed the five hundred soldiers in his past was due to the belief that weakness is a sin. Personally, he believes anyone who shows weakness is no better than a criminal.
Enel is the major antagonist of the Sky Island Saga. He thinks of himself as an invincible god – quite literally. He believes that he is a divine and immortal being, with the authority to do, take or destroy whatever he pleases and is capable of doing anything. Enel holds no regard for any life except his own, and has no moral qualms about killing thousands – instead he sees it as his godly duty, and laughs maniacally as he sends Skypiea to its doom.
Despite her elderly age of 68, Linlin has childish tendencies. She’s an extremely ruthless and unstable woman. She’s also immensely selfish and obsessed with power.
Big Mom is an extremely gluttonous pirate who loves to eat sweets above all else; she suffers from an unknown disease, in which she becomes obsessively fixated on a “Sweet Theme”, and will go on a crazed rampage in search of what she wants to eat.
Big Mom has proven herself to be extremely treacherous and cunning, as she is willing to break promises and betray potential allies to get what she wants.
Akainu is the current Fleet Admiral. He is cruel, heartless and believes in the Marines motto of “Absolute Justice”, which is to punish criminals at any cost. He will kill anyone that he thinks are evil or are an obstacle of justice. He will also not hesitate to kill his own comrades who run away from the battle. He will kill them no matter how they beg for mercy. He is one of Monkey D. Luffy’s archenemies after killing his brother Portgas D. Ace.
Doflamingo is a major antagonist in the Marineford Arc the main antagonist of the Dressrosa Saga.
He has immense arrogance, pride, and a carefree attitude. He is also completely calm and cool-headed in most situations.
Doflamingo likes to toy around with his opponents and victims in a sadistic and cruel ways. He seems to live by a “might is right” philosophy, believing that the strong are the ones who make the rules and will be the only ones capable of living in the “New Age”. However, he does have an extremely strong sense of loyalty, duty, camaraderie and compassion to the subordinates who had been with him for a long time.
Katakuri is a major antagonist of the Whole Cake Island Arc. He is a very cold individual and is capable of extreme brutality as shown when he pondered on how he should maim Luffy with his trident.
But he’s also a honorable man who dislikes other people interfering with his fights. Though he considers Luffy his enemy and desires to eliminate him personally before he can become a threat, he wishes to defeat him fairly. After discovering that Flampe was the one attacking Luffy and lowering his performance in the fight, Katakuri injured himself in the same spot he injured Luffy to compensate and angrily shouted at Flampe for interfering in his fight and revealed his full face to her to stop her meddling in the duel between men even if it caused Flampe to lose respect for him.
MARSHALL D. TEACH
Blackbeard is the archenemy of Monkey D. Luffy and is considered the evil counterpart of Whitebeard. He is highly amoral. He believes that there is no inherent “good” nor “evil” in the world, jeeringly mocking anyone who expresses such belief. He showed his ruthlessness when he killed Thatch, and with his crew’s help finished off his former captain, Whitebeard.