When Eiichiro Oda published One Piece's first chapter in 1997, he probably never expected his pirate story to become the most popular and successful manga series of all time, and the anime has received an equal amount of success and praise. The story follows Monkey D. Luffy, who is traveling the world with his crew in order to become the new Pirate King, and he has met quite a few interesting characters along the way.

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One Piece has been around for over two decades, and over that time, fans have been introduced to more than 900 characters, some of whom are more memorable than others. When a story has that many characters, it is impossible to give them all enough screen time, which is why they disappear or go away for a while. And there are quite a few currently sidelined characters that fans want to see again.

10 Kuro Hasn't Appeared Since The End Of The Loguetown Arc

Captain Kuro mad with blades One Piece

Kuro may be a smart and ruthless pirate captain who uses gloves that have full-length katana blades on each finger, but he's still an ordinary human who can be beaten by many characters. He was the main antagonist of the Syrup Village Arc, where he pretended to be Kaya's caretaker in order to steal her family's wealth.

After being defeated by Luffy, Kuro became the captain of the Black Cat Pirates again, and the last time fans saw him, he was looking at Luffy's first wanted poster, which was issued at the end of the Loguetown Arc. His current whereabouts are unknown, but if he does reappear, it will be interesting to see how he will interact with Usopp.

9 Bon Clay Hasn't Been Seen In The Anime Since Impel Down

One Piece Bon Clay Crying

Bon Clay was an important side character in the Alabasta Arc, and he and Luffy managed to become quick friends despite the fact that he was an enemy who worked in Crocodile's criminal organization. He possesses the Clone-Clone Fruit, which allows him to become a physical double of anyone he touches.

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He later appeared in the Impel Down Arc, where he sacrificed his freedom in order to help Luffy escape. He was presumed dead for a long time, but it was later revealed that he survived, and he is currently the Queen of the prison's Newkama Land. When he does return, his reunion with Luffy will undoubtedly be filled with tears and joy.

8 Katakuri Is A Great Fighter & He May Become An Ally Down The Line

Katakuri using the Mochi Mochi no Mi during his fight against Monkey D. Luffy in the Whole Cake Island arc

Charlotte Katakuri is one of Big Mom's many children, and he happens to be the strongest member of her crew because he possesses extremely powerful Observation Haki, as well as a Devil Fruit which allows him to create, control, and transform into mochi.

He had an incredibly intense fight with Luffy during the Whole Cake Island Arc, and it became quite clear that he developed a great deal of respect for the Straw Hat captain. Katakuri hasn't appeared in the Wano Arc yet, but given his popularity, he should appear again in the future, and when he does, he might be an ally.

7 Donquixote Doflamingo Is Arguably The Series Best Villain & He Knows The Celestial Dragons' Secret

Doflamingo laughing in One Piece.

Doflamingo went through something very traumatic as a child, and when he attempted to rejoin the Celestial Dragons, he was turned away, which is why swore revenge on them and became a pirate. He has the power to create and manipulate string, which doesn't sound impressive, but he can actually use this power to destroy an entire kingdom.

After losing to Luffy, Doflamingo was arrested and sent to Impel Down, where he is still a prisoner, but he still has some knowledge of current events. So far, Doflamigo is arguably One Piece's greatest villain, so it makes sense to bring him back from that perspective, but he also has knowledge of the Celestial Dragons' secret treasure, which is information Luffy will need in the future.

6 Arlong Hasn't Been Seen Since His Defeat Early In The Series

arlong one piece

Arlong is a sawshark fish-man who believes that humans are inferior beings, and he was the main antagonist of the Arlong Park Arc. A fish-man's physical strength is usually 10 times that of an ordinary human's, and Arlong was even stronger than that, which is why he was so dangerous without having a Devil Fruit power.

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Arlong was unbelievably cruel to Nami, and this was after he killed her adoptive mother in cold blood. He is currently in Marine custody, and if he were to return, it would be interesting to see if he has changed his ways, and the only way to do this properly, is to have him beg Nami for forgiveness.

5 Gin Said He Wanted To Meet Luffy Again

Gin Holding His Weapon

The Baratie Arc introduced fans to Sanji, but it was also the first and only time that Gin appeared in the story. Gin is the Combat Commander of the Krieg Pirates, and he was once fiercely loyal to his captain until he decided to stop following him after Luffy defeated him.

Gin actually respects Luffy for being a good person and captain, and he admires Sanji because he was the first person to ever show him kindness when he arrived on the Baratie starving. As Gin departed, he told Luffy that he hopes to meet him again in the Grand Line, which implies that he should appear again.

4 Smoker Is A Rebellious Marine & He Hasn't Been Seen Since Dressrosa

Vice Admiral Smoker smoking in One Piece.

Smoker started out as a captain stationed in Loguetown, but he has since risen to the rank of Vice Admiral. Thanks to the Smoke-Smoke Fruit, he can create, control, and transform into smoke at will, which is why Luffy had difficulty fighting him in their first encounter.

He is known for being a loose cannon and a rebellious marine who does not always believe in his superiors' actions. Smoker hasn't appeared since the Dressrosa Arc, but given his relationship with Luffy, the two may end up teaming up in the future during the series' final conflicts.

3 Pudding's Story With Sanji Hasn't Ended Yet

Pudding on her wedding day

Katakuri has a lot of siblings, including Pudding, who agreed to marry and kill Sanji so that her family could assassinate the Vinsmoke family and take control of the Germa Kingdom. At first, Sanji and the other Straw Hats thought that Pudding was an ally, but she later revealed herself to be a willing participant in the plan.

The problem though is that she genuinely falls in love with Sanji on their wedding day when he tells her that her third eye is beautiful. Pudding will definitely be back because her story with Sanji remains unfinished, and this is because she removed and saved portions of his memories with her Devil Fruit.

2 Crocodile Has Done Nothing Since The Summit War & He Might Be An Ally Now

Crocodile

When Crocodile was first introduced, he was one of the Seven Warlords, but he was also trying to take control of the desert kingdom, Alabasta. This made a lot of sense since Crocodile possesses the Sand-Sand Fruit, which allows him to create, control, and transform into sand.

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He may have beaten Luffy in their first encounter, but Luffy emerged victorious in the end, and this resulted in Crocodile being sent to Impel Down. It was there that he met Luffy again, but instead of attacking him, he agreed to help Luffy escape, and he continued to help him during the Summit War. Since the war, Crocodile has made cameo appearances, where he is smiling while reading about Luffy's accomplishments, which implies that he might be an ally down the line.

1 Enel Hasn't Been Seen Since The Skypiea Arc & He's Been On The Moon That Entire Time

Enel Lying Down & Meeting With His Minions In Skypiea

There may be characters who are stronger than Enel, but he is still one of the most dangerous characters that the series has produced. He was known as the God of Skypiea because he was able to create, control, and transform into lightning, and it helps that he has strong Observation Haki as well.

Luffy was able to counter Enel because of his rubber body, but in the end, the former God of Skypiea achieved his goal of traveling to the moon. Fans have wanted to see Enel return for years, partly because of how strong he is, but mainly because they want to know about his lunar exploits.

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