The world of One Piece contains many mysteries pertaining to powers and techniques that set the strongest pirates apart from the amateurs. One such technique is the Haki, an ability that allows users an array of remarkable feats such as precognitive abilities and a strong will that overpowers the will of others.

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There are three types of Haki, each with its own unique properties. Busoshoku Haki is one that presents immense power-level increase potential. Though a more common Haki, it presents a clear distinction between those who have mastered it and those who have not. Of the many who wield this form of Haki, here are the most proficient users.

10 Charlotte Katakuri

As a Sweet Commander and reliable Big Mom Pirates member, Katakuri's Haki proficiency is well known. Like many Haki users, he is able to imbue his Busoshoku Haki into his strikes. His most common technique involves mixing his Devil Fruit, the Mochi Mochi no Mi, with his Haki.

Katakuri boasts mastery over Busoshoku Haki, claiming to be better than Luffy at utilizing it during their confrontation. During said fight he was able to injure Luffy and deflect the Straw Hat captain's Haki-infused attacks, overpowering him and demonstrating his superior technique at the time. And while defeated, it's undeniable Katakuri is one of the most skilled Busoshoku users.

9 Roronoa Zoro

Amongst the three Haki forms, Zoro is most proficient in Busoshoku, commonly used to coat his swords and induce damage to Logia-type Devil Fruit users. Zoro was trained in this Haki under Mihawk, and proved his skill in the technique in his fight against Pica (who Zoro was able to cut through with his Haki-imbued swords).

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Now in wano, Zoro has exemplified increased command through employing Enma, Kozuki Oden's cursed sword with the ability to drain Haki. In spite of initially subjecting to his Haki being drained, Zoro was able to restore his Haki and later showed control over the sword in his fight against Kaido and Big Mom. He would later go on to leave a permanent scar on Kaido, something seldom have accomplished.

8 Akainu, Aokiji, and Kizaru

According to One Piece lore, Vice-Admiral ranked Marines and higher are expected to have certain mastery in Haki — as such, it's no surprise that the previous Admiral line-up, consisting of Akainu, Aokiji, and Kizaru hold tremendous Busoshoku Haki usage.

During Marineford, the three Admirals demonstrated an advanced, combined technique to negate Whitebeard's shockwave. This technique, known as Emission, is something very few can use, thus showing their Haki comprehension. And while more of their Haki abilities have yet to be shown, it's indisputable that their titles and minor showing of this Haki justify their placement on this list as some of the strongest combined forces in One Piece.

7 Kozuki Oden

Oden was said to be a Busoshoku Haki master, Busosoku being referred to on Wano as Ryuo. He showed remarkable promise from a young age, already able to coat his weapons and slice through the Mountain God. Later he would go on to wield Enma, showing better and more immediate command over it than Zoro.

Upon years of experience, he later developed a reputation as one of the only people able to wound Kaido in his dragon form, something that even to this day many of the most experienced Haki users have yet to do.

6 Kaido

With plenty of abilities at his disposal, it's no surprise that Kaido is also a powerful Busoshoku Haki user. Like many skilled Haki users, Kaido uses Busoshoku to strengthen his weapon (his giant kanabo) to increase his damage output. While using his kanabo, he can utilize Emission to project Haki, striking enemies from a distance with a powerful shock.

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Kaido's superiority in Busoshoku is evident by the numerous Busoshoku users he has overpowered, as shown when he managed to deflect and damage Luffy who had coated both of his arms during their first fight. This alone is enough to validate his higher skill level, but can also be proven with how much foes struggle to pose a match against him.

5 Charlotte Linlin

Charlotte Linlin, better known as Big Mom, is a pirate Emperor who seldom falters to other's strength, only ever being beaten due to her own mental weaknesses. As shown in her many battles, the Big Mom Pirates captain is incredibly skilled in Busoshoku Haki, primarily optimizing it for hand-to-hand combat by coating her arms.

In her battle against Luffy, Big Mom was able to deflect his Haki-coated technique with a single arm — and given that this attack was one of his most powerful, it's evident she possesses tremendous power with her Haki. And like the most powerful users, she can emit Busoshoku Haki from a distance.

4 Edward Newgate

Though his power levels decreased after passing his prime, Whitebeard was still considered one of the best Busoshoku Haki users while alive. As a younger pirate, Whitebeard exemplified incredible control over Busoshoku Haki, matching up alongside the likes of both Gol D. Roger and Kozuki Oden. In his matches against both fellow Haki users he displayed the ability to transfer his Haki into his weapon, Murakumogiri, and even the ability to strike foes from a distance using Emission.

Even as he grew older, Whitebeard was able to outmatch many opponents who were also capable Haki users, showing that his age and worsening health were but minor setbacks to his immense strength. He managed to damage and defeat many intangible opponents (most notably Logia-type Devil Fruit users) and earned the respect of many for this remarkable display of power.

3 Gol D. Roger

The legendary pirate Gol D. Roger is a notorious name amongst pirates and citizens alike whose power levels surpass even the most fearsome warriors in One Piece's modern day. Among many of his skills, Roger's Busoshoku Haki usage was one that rivalled the greatest users, being credited as a match for Whitebeard in his prime.

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Besides Whitebeard, Roger was able to both match and overpower proficient Busoshoku user Kozoki Oden, defeating him in a single swipe of his Haki-imbued saber. Beyond his legendary status being a testament to his expertise, his masterful use of Emission and overall proficiency do more than enough to validate why Roger is still considered the Pirate King.

2 Monkey D. Luffy

Despite his joyful and playful demeanor, Luffy is considered one of the most feared pirates in all of One Piece, especially after the timeskip in which he added Haki to his arsenal. Busoshoku is perhaps Luffy's most used Haki as he commonly mixes it with his Devil Fruit abilities to increase his offensive and defensive potential.

Though previously outdone by other Busoshoku users, he is now perhaps one of the most proficient wielders, having surpassed the most masterful of foes. Beyond the common imbuement technique and the rare ability to inflict distance-based damage, Luffy can now channel his Haki to destroy things from the inside — be it people or objects. Proof of his increased mastery include the ability to damage Kaido, being able to withstand attacks from Kaido, and destroying deadly collars and explosive handcuffs from the inside out. It's uncertain whether his Haki has reached its limits, but given his unlimited potential he is certain to only grow more powerful in the technique.

1 Silvers Rayleigh

Perhaps one of the greatest Haki users is Rayleigh, who served as the first mate for the legendary Roger Pirates. As the person responsible for training Luffy and fighting alongside Roger, it's clear that Rayleigh has a deep understanding of the technique — which is only further authenticated by his various victories and shows of strength. With his Haki, Rayleigh is able to bypass the limitations of Devil Fruit user's opponents, as shown when he was able to deflect Kizaru's light-based attacks.

What's more, he can use the difficult technique of projecting Haki at a distance and appears to be one of the best at it. But perhaps the most impressive demonstration of his Haki proficiency is his ability to force his Haki into an opponent, subsequently destroying them from the inside.

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