Roronoa Zoro

He is the first pirate to join Monkey D. Luffy, and the Straw Hat Pirates' main fighter, one of their two swordsmen and one of the main officers of the Straw Hat Grand Fleet, as well as a former bounty hunter.

Born in the East Blue, Zoro is the son of Tera and Roronoa Arashi, the grandson of Shimotsuki Furiko and Roronoa Pinzoro, and the great-nephew of Shimotsuki Ushimaru, making him a matrilineal descendant of both the Shimotsuki family of Wano Country and the legendary samurai Shimotsuki Ryuma.

He earned his first bounty of Belly 60,000,000 after the Alabasta Arc. It was later increased to Belly 120,000,000 after the Enies Lobby Incident, and again to Belly 320,000,000 after the Dressrosa Arc. After the Raid on Onigashima, his bounty increased to Belly 1,111,000,000, making it the second highest of the crew only surpassed by Luffy's.

Zoro has grown and now stands at 181 cm tall, with a new scar crossing his left eye. His body appears much thicker and more muscular.
He has a very serious look and wears three golden earrings in his left ear. His hair is green, which has caused Sanji to call him "Marimo" (a round, green seaweed). This has led to several very funny situations in which even he has been confused. He has a scar on his chest made by Mihawk in his duel against him. He also has two scars on his legs from when Nami, Vivi and he were captured by Mr. 3 during the Little Garden arc.
He always carries with him a black bandana that he usually wears tied around the forearm of his left arm, and he always ties it around his head when he is in serious combat, giving him a more sinister image that causes fear in many of his opponents, and some even claim that he is a real demon. Like Luffy, he usually changes his outfit in some situations.

Zoro is reserved, though often acting comically; he also has a poor sense of direction, to the point of getting lost even on straight paths or when someone is guiding him. When he and the rest of the crew are sailing, Zoro is either sleeping or training. He and Sanji have a great rivalry, fighting (verbally and physically) over unimportant matters and very often, in inopportune situations and/or moments, although when they cooperate (which is rarely the case) they form a great team.
He has a strong sense of reason that makes him the backbone of the crew when they reach a point where the situation is serious or critical (such as when Usopp left the crew). Regardless of whether he agrees or not, he will always back up Luffy's decisions (much like Robin), only speaking up to give his opinion when the others fail to see the true implications of the situation (such as when they face Aokiji). His only apparent job aboard the Going Merry is to use his enormous strength to raise the anchor, though lately (and since the Thousand Sunny has a mechanism to do that) he has been seen acting as a lookout.

Zoro is not as aggressive when confronting women, with Tashigi accusing him of looking down on them and not taking them seriously.
Zoro has also become more analytical and observant, being more strategic when fighting his opponents.

Three Swords Style:
Performing flying slashes in the Three-Sword Style, Zoro can create whirlwind-like attacks that have shown the ability to damage dozens of opponents at once. He is also able to effectively use his three swords to parry attacks, and can even counter attacks made by multiple opponents at once. [18] Zoro has not been shown to suffer many problems when dueling against opponents who wield more swords than him.

Two Swords Style:
The Two-Sword Style (二刀流, nitōryū?, lit. "Two-Sword Style") is Zoro's original sword fighting style from his childhood before he began practicing the Three-Sword Style. Like the latter, Zoro has immense mastery of this style of sword fighting, wielding two of his swords in combat with great skill, even incorporating unsheathing and re-sheathing techniques as well as flying slashes.

Style of a sword:
The One Sword Style (一刀流, ittōryū?) is a sword style that Zoro began to perfect and eventually come to master. Like the previous styles, Zoro has exceptional skills and mastery of the One Sword Style, and has repeatedly used this style to perform finishing moves against a variety of opponents. Like the Two Sword Style, this style utilizes flying slashes as well as various drawing and re-sheathing techniques, primarily to defeat or injure powerful opponents with a single attack.

Nine Swords Style:
The Nine Swords Style (九刀流, kyūtōryū?) is the most extreme application of Zoro's spiritual projection abilities. With enough anger, a dark aura surrounds him as two full apparitions of his body appear from within his body, giving him the essence of Nine Swords. Despite its seemingly purely spiritual nature, Zoro's attack power is tripled.

Fire Fox Style:
Zoro became interested in the Fire Fox Style, the unique sword style of Kin'emon, the leader of the Nine Red Scabbards, when he saw him use it against Smiley at Punk Hazard. Later, during the fight against Kaidou and Big Mom at Onigashima, it was revealed that Zoro had "stolen" this fighting style from him. As such, he can cut through flames, as shown when he bisected the homie Prometheus, injuring him. Despite this being his first time using it, Zoro has adapted to the style well, cutting through Kaidou's Bolo Breath, and later incorporating it into his regular sword styles.

Zoro is capable of using all three types of Haki. Zoro has specialized in Busoshoku Haki, with which he has demonstrated great mastery.
— Kenbunshoku Haki, which grants users a hidden instinct or sixth sense of the world around them and unlimited precognitive ability.
— Busoshoku haki, which allows the user to use their spirit as unbreakable armor to defend themselves from attacks, or to perform their own more powerful attacks.
—Haoshoku Haki, a rare type of Haki that only one in a million can use, and which grants the user the ability to overpower the will of others. Most people who can use Haki tend to have one type that they are best at, and as a result focus on enhancing that type. However, a person can improve their skills with all types of Haki, it just requires more effort.

• Wado Ichimonji (和道一文字, Wadō Ichimonji?, lit. "Thin Line of Harmony"): The sword given to her by Kuina's father. It has the most sentimental value, being one of the O Wazamono. Its price is estimated to reach Belly 20,000,000.
• Sandai Kitetsu (三代 鬼彻, Sandai Kitetsu?, lit. "Third Demon Slayer"): A daito that is said to be cursed with the death of its owner, is one of the Wazamono. It has a very sharp edge and its blade is a lilac/purple color. It was given to him by the owner of a sword shop in Loguetown when he made a show of will.
• Enma (閻魔えんま, Enma?, lit. "Devil"): It is one of the 21 wazamono that was once wielded by Kozuki Oden. Currently, due to Kozuki Hiyori's decision, it is in Zoro's possession. It is also known as the only weapon that has been able to injure Kaidou.

Zoro has a complicated personality, he is the best swordsman in the world. A person who fulfilled his dream with you and the others but only wants to protect you. He loves you so much that he doesn't want anything to happen to you and now it is even more so when you are pregnant with him. A boy or a girl is the least of his worries but he wants to secure his little family even with his life.

Three of the crew's best fighters, Luffy, Zoro, and Sanji, are called the Monster Trio due to their immense strength, while the three weaker ones, Nami, Usopp, and Chopper are called the Weak Trio.

Monkey D. Luffy (Captain):
Nickname: “Straw Hat”
Dream: Become the Pirate King and find the One Piece.
Roronoa Zoro (Swordsman):
Nickname: “Hunter of Hunters Pirate”
Dream: To become the best swordsman in the world.
Nami (Navigator):
Nickname: “Cat Burglar”
Dream: To draw a complete map of the world and navigate the entire Grand Line.
Usopp (Sniper and Liar):
Nickname: “Liar of the Seas”
Dream: To become a brave sea warrior like his father.
Sanji (Cook):
Nickname: “Black Leg”
Dream: To find the All Blue, an ocean where all the species of fish from the four seas are found.
Tony Tony Chopper (Doctor and Reindeer):
Nickname: “Brainiac”
Dream: To become a doctor who cures any disease.
Nico Robin (Archaeologist):
Nickname: “Demon Girl”
Dream: Discover the True Story and find the Poneglyph that reveals the location of the One Piece.
Franky (Carpenter and Cyborg):
Nickname: “The Man of 8,000,000” (for his bounty)
Dream: To build and sail a ship that circumnavigates the globe. (Current ship: Thousand Sunny)

Brook (Musician and Skeleton):
Nickname: “Soul King”
Dream: To meet his old crew again and see the sea he never sailed on.
Jinbe (Coxswain and Ex-Shichibukai):
Nickname: “Knight of the Sea”
Dream: Help Luffy achieve his dream and achieve coexistence between humans and fishmen.