
Farm the Moon Slayer boss, collect all seven materials, and unlock the F Move with this step-by-step Sailor Piece guide.
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updated
June 5th 2026
posted
June 5th 2026
Moon Slayer is the Kokushibo-inspired fighting style added in Sailor Piece's Moon Update, and it's one of the most visually striking specs in the game. Crescent moon particles fly off every M1, the V move summons an actual moon, and the F Move drops a black domain that ends with a single devastating forward slash. Getting there takes serious farming, but the path is straightforward once you know what to prioritize.
Moon Slayer is a late-game fighting style modeled after Kokushibo from Demon Slayer. Despite displaying a sword-like weapon in your hand, it's classified as a spec rather than a sword, so don't confuse it with the blade items in your inventory. The style was introduced with the Moon Update and sits among the strongest melee options currently available.
The Six-Eyed Demon Title you earn along the way isn't just a cosmetic flex. It's a hard requirement to purchase the fighting style from the NPC, which means you can't shortcut the boss grind by stockpiling gems early.
Head to Boss Island and find the Moon Slayer Trainer NPC on the opposite side of the island from the spawn point, facing the water. Hand over all seven requirements and the fighting style is yours.
Here's the full list:
| Material | Quantity | How to obtain |
|---|---|---|
| Six-Eyed Demon Title | 1 | Moon Slayer Boss (1% drop) |
| Gems | 37,500 | Quests, chests, boss drops |
| Moon Crest | 1 | Moon Slayer Boss (0.45% drop) |
| Crescent Shard | 4 | Moon Slayer Boss (1.06% drop) |
| Lunar Essence | 9 | Moon Slayer Boss (4.63% drop) |
| Demon Remnant | 16 | Moon Slayer Boss (13.41% drop) |
| Upper Seal | 25 | Any enemy, higher-level mobs preferred |
Drop rates listed above apply to normal difficulty. Observed rates during testing showed some variance, with Moon Crest appearing closer to 0.30% and Crescent Shard at roughly 0.70% in normal-mode runs, which suggests minor fluctuation is possible. Higher difficulty settings increase all drop rates but require more summon materials per run.
Talk to the Boss Summoner NPC on Boss Island and scroll to the Moon Slayer Spawn option. Each normal-difficulty summon costs:
The boss carries over 1.25 billion HP on normal mode. You should be at level 12,000 or above before attempting it solo. Below that threshold you'll burn through consumables faster than the drops justify.
The Extreme difficulty version increases drop chances for the rarest items, specifically Moon Crest and the Six-Eyed Demon Title, but the boss becomes significantly harder to kill. Bringing two or three players to an Extreme run is the most efficient approach if your build can handle the coordination.

Sailor Piece Guide: How to Get Moon Slayer
Upper Seals drop from any enemy in the game, but the rate improves substantially at higher-level zones. The best farming spots are Ninja Island, Lawless Island, and Shinjuku. Enemies here are high-level, respawn quickly, and give you better odds per kill than early-game zones.
Several things increase your effective drop rate:
You need 25 Upper Seals just to unlock the fighting style, plus 1 per boss summon, plus 85 more for the F Move. Plan your farming accordingly.
After testing the full kit on a melee-focused build, here's what each input does and the damage numbers attached to it:
| Keybind | Move description | Damage |
|---|---|---|
| M1 | Crescent moon particle slashes | 300M normal / 900M crit |
| Z | Forward slash into somersault combo | 2.3B |
| X | Two slashes into continuous forward technique | 3.5B |
| C | Lifts enemy, fills area with purple craters | 6B |
| V | Cutscene moon summon, powerful ground cut | 14.5B |
| F | Black domain, continuous slashes, single forward finisher | 25B |
The F Move Mastery NPC is on top of the upside-down hand statue on the right side of Boss Island. Climb to the top and interact with him. You'll need:
The Upper Clan is obtained by rerolling your clan affiliation. It grants +40% Damage, +50% Max HP, +12% Melee Damage, +12% Luck, and a 20% chance to deal 25% extra damage for 8 seconds on skill use. That last passive pairs well with Moon Slayer's heavy-hitting moves. Completing the F Move unlock also awards a permanent +30% Damage Buff for the style.
The two extra Moon Crests are the hard part. At a 0.45% drop rate on normal difficulty, expect to run the boss dozens of times before the second one shows up. This is where the Extreme difficulty summon earns its cost.
For a melee build, yes. The F Move alone hits 25B damage with a +30% buff attached, and the C and V moves give you strong AoE coverage for clearing groups. The fighting style's visual design is also among the best in the game right now, which matters if you're planning to flex the Six-Eyed Demon Title you earned getting here.
The grind is genuinely long. The Moon Crest bottleneck at 0.45% means some players will clear everything else and still be waiting on that last drop. Patience and Luck stacking are the only real answers to that.
For more Roblox and Sailor Piece guides, browse the full guides library at GAMES.GG to find tips on other fighting styles, weapons, and progression systems.
