Passive Shard is a legendary material in Sailor Piece that allows you to unlock passive abilities for your weapons. The item drops from NPCs throughout the game, though its legendary rarity means the drop rate is low. Once you collect Passive Shards, you can exchange them with the Passive Master NPC on Judgment Island to enhance your weapon capabilities.
Quick answer: Defeat any NPC in Sailor Piece to have a chance at receiving a Passive Shard drop. After collecting shards, travel to Judgment Island and speak with the Passive Master to unlock weapon passive abilities.

How to Farm Passive Shard
Passive Shard drops from any NPC enemy you defeat in Sailor Piece. The item has no location restriction—you can farm it anywhere in the game world where NPCs spawn. Because Passive Shard is classified as a legendary material, the drop rate remains consistently low regardless of which enemies you target.
The most efficient farming strategy is to defeat NPCs continuously in areas where they respawn quickly. Choose locations with high enemy density and fast respawn timers to maximize the number of kills per hour. Auto-farming settings can help maintain consistent progress if you plan to farm for extended periods.
No specific NPC type has a higher drop rate for Passive Shard. The drop chance applies uniformly across all standard enemies, so focus on clearing enemies quickly rather than hunting particular types. Group farming or using area-of-effect abilities can speed up the process by allowing you to defeat multiple NPCs simultaneously.

How to Use Passive Shard
Step 1: Travel to Judgment Island after collecting at least one Passive Shard. Judgment Island is accessible once you have progressed far enough in the game to unlock travel to that location.
Step 2: Locate the Passive Master NPC on Judgment Island. This NPC handles all passive ability unlocks for weapons in Sailor Piece.

Step 3: Interact with the Passive Master and select the weapon you want to enhance. The NPC will present available passive abilities you can unlock using your Passive Shards.
Step 4: Confirm the passive ability unlock by spending the required number of Passive Shards. The passive ability will immediately apply to your selected weapon.

Each weapon can have multiple passive abilities unlocked, and different passives may require different quantities of Passive Shards. The Passive Master interface will display the cost for each unlock option before you commit your materials.
Passive Shard Drop Rate and Farming Tips
The legendary classification of Passive Shard means you should expect to defeat a significant number of NPCs before seeing a drop. Plan for extended farming sessions rather than expecting quick results. Setting up an efficient farming route or using auto-combat features can reduce the active time investment required.
Private servers can improve farming efficiency by eliminating competition for NPC kills. If you have access to a private server, you can control spawn areas without interference from other players. This setup is particularly useful for overnight farming sessions where you want consistent NPC availability.
Track your Passive Shard inventory through the game's materials menu to monitor your progress toward the number of shards needed for your desired passive unlocks. Some passive abilities may require multiple shards, so knowing your current count helps you plan which unlocks to prioritize.

Passive Abilities and Weapon Enhancement
Passive abilities provide permanent stat bonuses or special effects to your equipped weapon. These enhancements remain active as long as you have the weapon equipped, making Passive Shards a valuable long-term investment for your primary combat gear.
The specific passive abilities available depend on the weapon type you bring to the Passive Master. Different weapon categories—swords, melee combat styles, and other equipment—have distinct passive ability pools. Review the available options for your weapon before spending shards to ensure you unlock the most beneficial abilities for your playstyle.
Once unlocked, passive abilities cannot be removed or transferred to other weapons. Choose your enhancements carefully, prioritizing weapons you plan to use for extended periods. If you switch to a new weapon later, you will need to farm additional Passive Shards to unlock passives for that equipment.