Armament Haki (Busoshoku Haki) is a form of Haki that allows the user to use their spirit to create, in essence, an invisible armor around themselves. Notably, this form of Haki can be used to injure Logia Devil Fruit users and allows the user to defend against attacks that would otherwise cause them harm.
Here’s the list about the strongest Armament Haki Users. Of course the list contains only those characters who have already shown this ability:
12 – TRAFALGAR LAW
Law has shown great proficiency in Busoshoku Haki, able to block Doflamingo’s Goshikito which is powerful and sharp enough to slice Issho’s meteorite and also took out a large portion of the palace without getting injured at all.
11 – JINBE
Jinbe is extremely skilled in using Busoshoku Haki, as shown when he defended himself against some Big Mom Pirates. He could also fortify his arms and was able to briefly defend against Big Mom’s Cognac. In the past, he could fight equally against Ace, an extremely powerful Logia user.
10 – MONKEY D. LUFFY
Luffy seems to have also mastered Busoshoku Haki to an extremely high extent, which has been shown to darken his body (or parts of it) and harden it. This is first shown being used when he easily defeated a Pacifista with a single Haki imbued punch used in conjunction with his Gear Second.
9 – RORONOA ZORO
Being his personal Haki specialty, Zoro has extraordinary mastery of Busoshoku Haki. During the Dressrosa Arc, it is revealed that Mihawk taught Zoro how to imbue his swords with Haki. He can imbue Busoshoku Haki into all three of his swords at once; in doing so, he managed to cut down Pica, who had already covered his entire body with the same Haki, thereby also demonstrating his supreme mastery over Haki as compared to the Donquixote top executive.
8 – FUJITORA
Fujitora could clash head on physically with Sabo, a Logia-class Devil Fruit user and also a proficient Busoushoku Haki user, demonstrating an extremely high level of skill in Busoshoku Haki. He could focus strong concentration of Busoshoku Haki into his sword, turning it obsidian black and making it strong enough to defend against the razor sharp threads of the Birdcage, which can slice cannonballs and buildings with great ease.
7 – CHARLOTTE CRACKER
Cracker has incredible mastery of Busoshoku Haki, which he uses to harden his sword and biscuit armor. Luffy, a highly proficient expert of Busoshoku Haki himself, described Cracker’s Busoshoku Haki as extremely tough, which can easily withstand Luffy’s Haki enhanced strikes. After imbuing his sword with Haki, Cracker was able to cut Luffy’s arm while he was fighting in Gear Fourth, further demonstrating the power of his Haki.
6 – CHARLOTTE KATAKURI
Katakuri is extremely skilled at using Busoshoku Haki, as shown when he imbued his mochi leg with it in order to bludgeon and injure Luffy. He can also harden his arm, as shown when he countered Luffy’s attack. His Haki enhanced strikes are powerful enough to counter and overpower Luffy’s own Haki enhanced attacks, and he has boasted that his Busoshoku Haki is superior to Luffy’s.
5 – SABO
Sabo has shown incredible mastery of Busoshoku Haki, which he can imbue into his arm or his pipe. His Busoshoku Haki is strong enough to shatter Burgess’s Haki infused right arm armor, as well as Diamante’s sword. His mastery of Busoushoku Haki is superior to Bastille’s, as seen when the Vice Admiral attempted to cut him down with Haki enhanced sword strikes; not only did Sabo manage to block his Same-kiri Bocho, he even managed to destroy the entire blade with relative ease.
4 – SHANKS
Shanks has mastery over Busoshoku Haki, as during the Battle of Marineford, he imbued Busoshoku Haki into his sword in order to block a magma attack from Akainu.
3 – BIG MOM
Big Mom has immense mastery of Busoshoku Haki. By hardening her arm, she could easily block Luffy’s Gear Fourth Kong Gun, a tremendous feat as Luffy’s Kong Gun is powerful enough to break through powerful Haki based defenses of highly skilled Busoshoku Haki users such as Doflamingo, Cracker and Katakuri.
2 – SILVERS RAYLEIGH
Rayleigh has an extremely high level of skill in Busoshoku Haki, allowing him to effectively bypass the powers of a Devil Fruit user and touching the “substantial body” beneath whatever protection the fruit provides as seen when he used Busoshoku Haki to kick and redirect an attack from Admiral Kizaru. Rayleigh’s immense proficiency in Busoushoku Haki allows him to use it for devastating offense.
1 – MONKEY D. GARP
He demonstrates extremely proficient skill in Busoshoku Haki, being able to injure Luffy several times, bypassing his rubber body. He could harden his fist and turned it obsidian black, allowing him to counter and even crush Chinjao’s Haki-enhanced drill shaped head 30 years ago, proving his superior mastery compared to Chinjao, who himself is a powerful expert Busoushoku Haki user in his own right. During the Battle of Marineford, he managed to punch and hurt Marco despite the latter being in his regenerative phoenix form.