Armament Haki, also called Buso, is the power that lets you land hits on Logia fruit users in Haze Seas. Without it, your attacks pass straight through them. It also adds a permanent damage bonus to your swords and fighting styles, which is why most players grab it the moment they hit the level requirement.
Quick answer: Reach Level 350, travel to Logue City in Sea 1, and pay Old Man Silver $100,000 to learn Level 1 Buso Haki. Press J to activate it, then land hits with it active to earn EXP toward higher levels.
Where to unlock Armament (Buso) Haki
The trainer is a character named Old Man Silver, who resembles Rayleigh from One Piece. He stands in Logue City in Sea 1, near the door of a house toward the left corner of the island. Talk to him once you meet the requirements to buy the base skill.
| Requirement | Detail |
|---|---|
| Trainer | Old Man Silver, Logue City (Sea 1) |
| Level | 350 |
| Cost | $100,000 |
| Activation key | J |
You earn levels and cash by clearing enemies and finishing quests from the Quest NPCs, so you will usually have both ready by the time you reach Logue City on the normal route.
What Buso Haki does when active
Press J and your character’s limbs or weapon turn black, which confirms the Haki is on. While it is active, you gain two benefits. You can damage Logia fruit users, and your fighting style and sword damage go up by the current level’s bonus.
Note: The Buso damage bonus only applies to fighting style and sword skills. It does not increase Devil Fruit skill damage, so a fruit build gains only the Logia-hit ability, not extra fruit damage.
Every Buso Haki level and EXP requirement
Leveling is based on how many attacks you land while Buso is active. Each level raises the damage bonus, and the final level adds damage resistance on top. You cannot skip tiers, so every milestone must be completed in order.
| Level | EXP to reach | Effect |
|---|---|---|
| 1 | Unlocked at Level 350 ($100,000) | +2.5% damage |
| 2 | 5,000 | +5% damage |
| 3 | 20,000 | +7.5% damage |
| 4 | 50,000 | +10% damage |
| 5 | 100,000 (+ quest) | +15% damage and +10% damage resistance |
EXP roughly equals hits landed, so reaching Level 2 takes about 5,000 attacks, Level 3 about 20,000, and so on. Want to check your progress? Use the ;busoexp me command to see how many imbued strikes you have thrown.
Completing the Level 5 quest with the Armament Expert
Levels 2 through 4 unlock automatically as you build EXP. Level 5 is different. Once you reach Level 4 and grind out the full 100,000 EXP, you have to finish a quest from the Armament Expert NPC on Flower Capital island in Sea 2.
How to confirm each level unlocked
Two titles act as clear checkpoints. Reaching Buso Level 1 grants the Ironfist title. Hitting Level 5 after finishing the evolution quest awards the Void-Forged Arms title. Seeing either title confirms the level applied correctly.
A few things commonly stop progress. You will not gain EXP if the Haki is not active, so watch for the black limb effect before you swing. You also cannot skip ahead to the Expert’s quest before completing Levels 2 through 4 in sequence. And if you are short on the 200 Gems, the Level 5 quest will not finish until you deliver them.
Values here follow the current game data and can shift with updates, so treat the EXP figures as a reliable guide rather than a permanent guarantee.
