Armament Haki is an ability that temporarily increases the user's melee damage output, block durability, and allows them to touch Logia Type Devil Fruit users. The length and effects of the ability increase the longer it is used.
The maximum possible damage increase is +20%, whereas the maximum time limit is 1 minute and 55 seconds. It takes around 2 days of use to max with the reward for maxing it being a new swirling purple effect on your swords while the ability is active. (only visible at Graphics Level 4+)
Busoshoku Haki can be obtained as a reward for completing Ray's level 80 quest on Kori Island, which requires an up-front payment of 25000 and the defeat of 100 Yetis. This quest may take more than an hour to finish, and usually, it'll take a few hours.
It is possible to complete the quest with Suke-Suke in under 30 minutes by spamming rock throw (must have at least 30 stat points in devil fruit) and Bazooka after gathering all 6 together. Rokushiki is also a good alternative to completing this quest if you gather the Yetis into a house and use Rankyaku while taking cover.
It is also possible to complete the quest with Bomu-Bomu in about 30 minutes from only killing 4 Yetis) by using Self Destruct (must have at least 85 stat points in devil fruit) and wait until you have full health. (Self Destruct damage depends on how much defense stat points you have.) This is a good method even if you just kill the 4 that spawn near each other and could be done even faster if you decide to gather up all 6.
You could also gain enough defense to block 3 of their punches and then punish them while they're in endlag. (Fixed as of Update 4)
- Making some (very rough) mathematical approximations, and assuming the formula is linear and non-exponential, the player's Haki damage increases at a ratio of roughly 1% for every 2.125 - 2.250 seconds added to the Haki's timer. seemingly the only Devil Fruit other than Suke-Suke that gets a boost from Haki usage, the moves of the Gomu-Gomu also get damage increases with haki active. Another possible error would be the unchanged damage of the 1 Sword Style's Dragon Blaze.
- Busoshoku Haki can deflect bullets (not coated in Haki) while blocking, dealing no damage to your block. However, deflecting bullets does not deal damage to the attacker.
- You can evolve Busoshoku Haki into Busoshoku Haki V2 in the Second Sea.
- Busoshoku Haki was nerfed and now only gives a 15% damage increase while the max duration is 1 minute and 55 seconds.
- The player is able check if they have trained it to max if their sword has this animation.