V1[]
Busoshoku Haki/Armament Haki is an ability that can be bought at the Bubble Island in the first sea for 500k beli. When on, it coats the user's arms in black (or legs if you are using Dark Leg/Black Leg which Sanji uses.) It gives a damage buff for all swords and fighting styles (except Ancient Sword), as well as letting the player use these to damage Logia users. It is essential for combat, especially for people who main sword and melee, and is overall useful for PvP and PvE. It also adds an effect for some swords, giving select ones an aura.
V2[]
To get Buso Haki V2, you must first be at least level 3600 and have the V1. Once these are accomplished, go to Lee, who is located by the dock of Marine HQ. He will tell you to find Pung, who is located at Pirate Skull in one of the buildings. Talk to him, then he will give you a quest to defeat Dark Beard. Upon completion, you will receive a message that says "Pung is feeling happy". Talk to Pung again, then you can go back to Lee to claim your Buso Haki V2 for 35M Beli.
Once you have the V2, you will be able to change the color of your Haki. There are two sellers for this: one near Lee at the Marine HQ, and another in the first sea inside of the spawn building. There is another NPC that shows you which colors you have gotten so far and to equip them if you like. The NPC is located in one of the towers at Marineford and in the mansion at Fiore.
Busoshoku Haki -V2 gives a better damage buff for swords and fighting styles than V1 does, and you are also able to change the outline color of it (see above).
The Haki v2 colors available thanks to shroom are (White, Green, Lime, Yellow, Carmine/Red, Fuchia, Ultramarine, Azur, Apricot, Indigo, Arc)
For example the Apricot color:
Level armament[]
Since update 5, an armament stat was added. There are 6 levels to armament, each level allowing the Busoshoku Haki to cover more of the body. To achieve 6 levels in armament, you are required to hit NPC's a total of 40,000 times with Buso/Armament Haki active using a fighting style or sword. It is suggested to have no stats in fighting style, as well as using a logia fruit. Clicking the ~ next to armament stat lets you change the stage of Busoshoku, this doesn't change stat buffs. Each level of Busoshoku Haki increases the damage and defense by 1% (6% total buff when maxed).
Armament stages[]
You can do Punches only with M1 sword/fighting style.
Half legs is only covered if you have dark leg fighting style.
1 level - 0 punches. Half arms/half legs covered
2 level - 2500 punches. Full arms/full legs covered
3 level - 7500 punches. Full arms/ full legs and torso covered
4 level - 15000 punches. Full arms/full legs, torso and head covered
5 level - 25000 punches. Full arms/full legs, torso, head, half legs/half arms covered
6 level(max) - 40000 punches . Full body covered
Trivia[]
-To easy farm 6th stage you should have 0 points in sword/fighting style and logia. After this stack up from 4 to 8 npc's around you and use auto clicker. Npc cant punch you because of logia but you cant kill them because low M1 damage.
-For players who dont own Logia there is another method. First you will need to have either shift lock or the teleport ability, then equip a weapon or melee (Dragon's Standard is recommend since it has a slightly faster m1 speed, plus less end lag), then go to pirate island at 1st sea, lure 6 swordsmen clowns and stand near an orange house. Right behind it there is a gap you must fit in so make sure your character is sideways (or else he wont fit) if you struggle to get inside or dont have shift lock for some reason just use teleport/flash step. now all your need is turn on auto click while facing against the wall where the npcs will stand outside without hitting you. (also, if you for some reason want to to check their health you can use your observation haki). Just keep repeating the process until you kill them. You will get around ~2.5-3k progress per 6 npcs killed (If you dont have any stats on said weapon or melee).