Nami is the navigator of the Straw Hat Pirates, after officially joining the crew at the end of the Arlong Park Arc. Having had her village rescued by a defiant Luffy, Nami willingly joins the Straw Hats on their adventures.

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In her time, her navigational skills has shone through. Her ability ensures the Straw Hats can carry along sailing even in the dangerous and unpredictable weather of the New World. Nami dreams of one day drawing a map of the entire world, and being the navigator in the future Pirate King's crew is a surefire way to achieve that. With that in mind, here are 5 One Piece characters she can defeat and 5 more who she can't.

10 CAN'T DEFEAT: SHIRAOSHI

One Piece - Mermaid Princess Shirahoshi - Poseidon

Shirashoshi is a princess of the Ryugu Kingdom, being the youngest child of King Neptune and his late wife, Otohime. She is the ancient weapon, Poseidon, who can communcate with the Sea Kings. Though Shirahoshi is a kind and sweet girl, her abilities means she could turn out to be one of the most dangerous creatures in the One Piece world.

Shirahoshi's size means she could be difficult for Nami to deal with in a battle. Of course, Zues might aid her in overcoming this. But, if the Sea Kings realise Shirahoshi is in danger, they won't merely sit back and Nami won't be able to do much against such powerful beasts.

9 CAN DEFEAT: REBECCA

Rebecca was introduced during the Dressrosa arc as a gladiator who was fighting in the famous Corrida Colosseum. She is the daughter of Jyros and Scarlett, and is currently a lady-in-waiting of Dressrosa Kingdom.

During her fights at the Colosseum, Rebecca often avoided being hit due to her incredible dodging abilities. Her agility is her strongest asset and, as such, she built her fighting style around it. This allowed her to claim many a victory in the Corrida Colosseum but, if faced with the threat of Nami and her Zeus thundercloud, she would surely be defeated.

8 CAN'T DEFEAT: BIG MOM

Big Mom wielding her two strongest weapons, Zeus and Prometheus, against Brooke during One Piece's Whole Cake Island arc

Big Mom is the queen of Totto Land and currently the strongest woman in the One Piece world. Charlotte Lin Lin was born with overwhelming strength and she has proven to be hard to handle ever since she was a child.

A young and hungry Lin Lin went on a rampage and destroyed a town in Elbaf when she was merely a child. This level of strength means that only an exclusive few pirates can ever hope to put up a fight against Big Mom.

7 CAN DEFEAT: ALVIDA

alvida from one piece

Alvida was first introduced as a great and fearsome foe before Luffy quickly handed her a reality check, that is. Since then, she's consumed a Devil Fruit and allied herself to the former Warlord of the Sea, Buggy the Clown. These events have led to her taking great strides as a pirate, and her Devil Fruit's powers means she would be quite a troublesome match for many pirates.

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Her Slip-Slip Fruit abilities allow her to evade many types of attacks, but an attack from Nami's Zeus empowered Climatact could easily wipe out Alvida, despite her improvement over the years.

6 CAN'T DEFEAT: NICO ROBIN

nami and robin

It is believed that, before joining the Straw Hat crew, Nico Robin was one of the most callous women on the sea, often abadoning her crew to save herself. She was a "devil" who could destroy the world if allowed to live, due to her ability to read the Ponyglyphs. This caused the government to hunt her down and, to survive, Robin had to become strong and do everything she could to grow.

This turned her into a cold and calculating woman who could handle herself in a fight. Her Devil Fruit's ability would give her the upper hand in a fight against Nami, due to the latter's over-reliance on her Climatact.

5 CAN DEFEAT: ZALA

Zala or Miss Doublefinger (as she was known while apart of the criminal organization Baroque Works) is the current owner of Spiders Cafe, where she works alongside several of her former associates. Zala consumed the Spike-Spike fruit and true to its name, the fruit gave her the ability to turn her body into spikes.

These spikes are sharp and strong enough to easily pierce through reinforced concrete walls. Despite this ability, Miss Doublefinger was no match for Nami way back in Alabasta. This was back when Nami was a far inferior fighter, meaning Zala would surely lose should they have a rematch.

4 CAN'T DEFEAT: BOA HANCOCK

After being freed by Fisher Tiger, Boa Hancock and her sisters escaped and eventually built up their strength, and were recruited into the Seven Warlords system. After seeing that system fall apart, the Kuja pirates and Hancock are now enemies of the government once again, meaning that the Pirate Empress is now free to bear her fangs at the world once more.

Hancock has shown great skill in Haki, which alone puts her into a totally different category to Nami; one that Nami can't simply surpass with her Climatact alone. At least, not yet.

3 CAN DEFEAT: VIOLA

Viola As Violet Of The  Donquixote Pirates

Viola is the current crown princess of Dressrosa, having formerly joined the Donquixote family under the command of Donquixote Doflamingo. During this time, serving as an officer in the family in order to protect the citizens of Dressrosa and King Riki, Vola had to stand by and watch as her once beloved country fall into the hands of Doflamingo for years.

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Her Glare-Glare fruit grants her impressive perceptive abilities, which can be a great aid in large scale missions. She is also a highly competent fighter, which would make her a challenge for Nami. But, with Zeus' help, Nami should be able to overcome Viola.

2 CAN'T DEFEAT: SHAKI

Shakky is currently the owner of Shakky's Rip Off Nar and the current wife of the right hand of the former Pirate King, Silvers Rayleigh. Before settling down on Sabaody with Rayleigh, Shaki was a notorious pirate who was often chased around by Monkey D Garp in his prime.

Despite this, she was never captured, which stands as a testament to both her and her crew's strength. This has led many to believe that she's a former member of the Rocks Pirates, though it has yet to be confirmed. It is certain that Shaki can handle herself and with her ability, plus experience from decades of piracy, she would be victorious if Nami and her were to do battle.

1 CAN DEFEAT: KALIFA

Kalifa cp9 smiling in One Piece

Kalifa is a former member of the secret government organization, Cipher Pol 9, where she served for many years with great distinction and class. After mastering the Rokushiki techniques, Kalifa became a superhuman who was capable of easily defeating many of her enemies.

In Enies Lobby, she consumed the Soap-Soap fruit and her abilities improved to an even higher level. Despite this, she was still defeated by Nami during Ennies Lobby and, if the fight was to be repeated, the results would not change.

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