Ever since the One Piece timeskip, Busoshoku Haki has been a basic necessity on the battlefield.
One Piece characters have the ability to manifest their willpower into a spiritual energy. There are three different types, but the most common one is Busoshoku Haki. Users can effectively coat themselves with invisible armor. It's a very useful technique for offensive and defensive purposes.
Some of the strongest One Piece characters are highly proficient with it. This list is entirely dependent on what has been shown on screen. Extremely powerful fighters like the Admirals won't be listed, simply because they haven't been seen using Busoshoku Haki all that much.
Note: This article will contain a few manga spoilers.
Busoshoku users with the most impressive feats in One Piece
10) Kozuki Oden
Kozuki Oden is regarded as the most powerful samurai in Wano Country's recent history. He is among the very few people who can tame the cursed sword Enma. Kaido spoke highly of his skills since he knows from firsthand experience.
During his final battle with Kaido 20 years ago, Oden coated his legendary blades with Busoshoku Haki. This allowed him to deliver Togen Totsuka, a powerful technique that permanently scarred the dragon. This feat wouldn't be replicated until Zoro did it 20 years later.
On a related note, Zoro is also a very proficient user of Busoshoku Haki. Now that he wields Enma, he will undoubtedly surpass Oden in the very near future.
9) Silvers Rayleigh
Rayleigh first demonstrated that Logia users are not immune to physical attacks. Before the One Piece timeskip, he managed to draw blood from Kizaru back in the Sabaody Archipelago.
Keep in mind that Logia users are mostly intangible fighters. Their exceedingly rare Devil Fruits allow them to become a natural element. Only those who have mastered Busoshoku Haki can bypass such defenses.
Rayleigh used to be Gol D. Roger's first mate, so his strength is not surprising. Either way, he still damaged a highly skilled Admiral.
8) Monkey D. Luffy
The main protagonist of the One Piece series, Luffy has trained himself very hard in the past few years. His mastery of Busoshoku Haki is far superior to most users, such as Doflamingo in the Dressrosa arc. Luffy can dish out devastating blows with his Gear Fourth abilities.
During the Wano Country arc, he also learned some advanced techniques. He can now hit opponents indirectly, which is a very rare ability in One Piece.
Luffy could easily be higher on this list. However, the Straw Hat is only slightly behind the Yonko. He bruises and bleeds more easily, which means his Busoshoku Haki isn't at their level. Kaido and Big Mom are constantly protected by their invisible armor.
7) Dracule Mihawk
Ever since his introduction in the One Piece series, Mihawk has been considered the best swordsman in the world. He yields the fabled Yoru, a legendary black blade that can easily cut through anything. Very few swordsmen can even hold a black blade in their hands.
During the One Piece timeskip, Mihawk taught Zoro how to coat his weapons with Busoshoku Haki. This fully protects weapon from powerful attacks. It's clear that Mihawk is quite the expert on the subject.
6) Shanks
The Yonko are considered the strongest pirates in the One Piece series. They are expected to master Haki in various forms.
Shanks has only been seen using Busoshoku Haki once, albeit in very impressive fashion. At the very end of the Summit War, he blocked a direct attack from Akainu, despite the latter's magma properties. Shanks can infuse Haki into his main weapon, thus leaving it unscathed.
5) Charlotte Linlin - Big Mom
Way back in Whole Cake Island, Big Mom effortlessly blocked Luffy's Gear Fourth attacks. This is a wonderful feat by One Piece standards. Remember, the Straw Hat completely destroyed characters like Doflamingo in this form.
Unlike most One Piece characters, Big Mom can also use advanced techniques with Busoshoku Haki. During the Onigashima Raid, she easily defeated Page One without even touching him.
4) Kaido
When he is bothered to use Busoshoku Haki, Kaido is nearly unstoppable with his kanabo. During the Onigashima Raid, he significantly damaged Luffy despite the latter hardening his own arms. Kaido's attacking power is already through the roof. Haki just makes him that much stronger in One Piece.
He doesn't use it often, but he is the world's strongest creature. A single blow from Kaido can break several bones. It's very telling that he saves his monstrous Haki for elite fighters like Luffy and Zoro.
3) Monkey D. Garp
It can be argued that Garp is the first One Piece character to demonstrate Busoshoku Haki. The Vice Admiral used it against Luffy back in Water 7, which completely bypassed the latter's rubber properties.
Garp is known as The Fist for very good reasons. Busoshoku Haki makes his physically strong punches even stronger. During the Marineford arc, he did what nobody else could by striking down Marco the Phoenix with a single hit. Remember, the latter has a bounty of 1,374,000,000 bellies.
Luffy's grandfather has a notable habit of easily taking down foes with minimal effort. Back in the day, Garp crushed Don Chinjao with a mere punch. Keep in mind that Chinjao in his prime can split continents with a headbutt.
2) Edward Newgate - Whitebeard
Despite his failing health, Whitebeard shook the very foundations of the world during the Marineford arc. He mastered Busoshoku Haki, since he can directly attack Logia users with his legendary weapon Murakumogiri. Whitebeard has previously beaten Ace and Crocodile in the past.
In a brief skirmish with Akainu, the pirate did something nobody else could do. Whitebeard dealt major damage just by using his Busoshoku Haki. It completely nullified the intangibility of the Magu Magu no Mi.
1) Gol D. Roger
There is nobody quite like the Pirate King himself. Roger completely breaks the scale of the One Piece universe.
He finally got to show off his skills during a flashback in the Wano Country arc. This is the scene where Roger famously clashed with Whitebeard on a random island. Before that, he briefly engaged with the powerful Kozuki Oden.
Roger is a master of Busoshoku Haki, especially when infused with his main weapon. He easily swatted Oden away like a fly just by using his Kamusari technique. It's no surprise that Roger can also stalemate Whitebeard, who uses a Supreme Grade Meito himself.
Note: This article reflects the writer's personal views.