Buso Haki in Haze Seas levels up from one thing only: the total number of successful strikes you land while it is active. Every hit counts as progress, so the fastest route to maxing it is to land as many hits as possible per enemy before that enemy dies. The trick is to keep enemies alive longer and stop them from hurting you back.
Quick answer: Set your Sword stat to 0, equip the Pillow sword, activate a Logia fruit like Flame for immunity, then cluster five Samurai enemies together and strike them nonstop. With zero sword damage, the Samurai stay alive while you rack up thousands of Haki strikes, and the Logia immunity means they cannot damage you during the grind.
Why the zero-sword setup works
Two mechanics make this grind possible. First, Buso Haki experience comes purely from landing hits, not from how much damage those hits deal. Putting 0 points into the Sword stat means each Samurai survives far longer, letting you land dozens of hits per enemy instead of killing it in a few swings.
Second, a Logia-type fruit grants immunity to physical attacks from lower-level NPCs. When the Flame fruit is active, you will see the “Logia immunity active on NPCs” message, which confirms the Samurai cannot damage you. Together, these let you stand inside a crowd of enemies and swing forever without dying or clearing them out.
Setup before you grind
| Requirement | What to set |
|---|---|
| Sword stat | 0 points |
| Other stats | Max Combat, Defense, and Fruit |
| Sword | Pillow (low damage) |
| Fruit | A Logia type such as Flame |
| Enemies | Samurai, in the Second Sea |
| Check-in NPC | Baji, the Armament Expert |
Note: you can reset and reallocate your stats so the Sword line reads 0 while Combat, Defense, and Fruit sit at their caps. The Pillow is the ideal weapon here because its damage is low enough to keep enemies alive through many swings.
The Samurai grinding method
Buso Haki levels and strike thresholds
You first buy Buso Haki V1 from Old Man Silver in Logue City at Level 350 for 100,000 Berries. After that, every level comes from landing hits with Haki active. The final level requires a separate quest from the Armament Expert.
| Level | How to unlock | Effect |
|---|---|---|
| 1 | Buy from Old Man Silver (Level 350, 100,000 Berries) | +2.5% damage |
| 2 | ~5,000 successful Haki strikes | +5% damage |
| 3 | ~20,000 successful Haki strikes | +7.5% damage |
| 4 | ~50,000 successful Haki strikes | +10% damage |
| 5 | ~100,000 strikes, then clear the Armament Expert quest (take 1,000 hits, pay 200 Gems) | +15% damage, +10% damage resistance |
The Samurai cluster method feeds directly into these strike counts, so it is the quickest way to push from one level to the next up to the point where the final quest takes over.
How to confirm your progress
Return to Baji after a grinding session. His dialogue shows your running total of strikes imbued with Haki and the number still needed to advance. If the “strikes so far” figure has climbed and the “more strikes for upgrade” figure has dropped, the grind is working. A single strong session can shave more than 1,000 strikes off the requirement.
If your counter is not moving, check two things. Make sure the Logia immunity message is active so you are not dying or being knocked out of the group, and confirm your Sword stat is still at 0 so the Samurai are not dying too quickly to farm. Keep the cluster tight and keep swinging, and each level threshold falls in order until you reach the Armament Expert quest for the final upgrade.
