Published: April 28, 2026 
Crystal Defense is one of the best endgame modes in Sailor Piece right now. It is locked behind Sea 2, so you need to be a late-game player to even access it. But once you are there, it is one of the best ways to farm rare items and upgrade your stats. This guide covers everything about Crystal Defense in Sailor Piece, from how to enter it to how to AFK it properly.
Where Is Crystal Defense in Sailor Piece?
Crystal Defense is on Punch Island in Sea 2. Once you unlock Sea 2, use the portal to get there. When you land on the island, take the road on the left side where the Fast Ninja NPCs are, and you will see the Crystal Defense NPCs at the end.
You can't just enter this area easily. To enter, you need Crystal Keys. You can get them by killing NPCs in Sea 2. The Fast Ninja NPCs on Punch Island are a popular spot since there are two groups of them close together.
Sailor Piece Crystal Defense Guide
Once you have at least one Crystal Key, head to the Crystal Defense NPC on Punch Island and interact with the Crystal Defense NPC on the right side. Click the Spawn button to open a portal, and the run will start after a short timer.
If someone else already spawned a portal, just walk up to it and hold E to join their run. Up to 4 players can be inside one Crystal Defense at the same time.
Now, here is the explanation of how the mode actually plays out once you are inside:
1. The Crystal
When you load in, there is a crystal in the middle of the arena with 100% HP. Enemies spawn from all sides every wave and rush toward it. Your job is to kill them before they reach it and deal damage. If the crystal hits 0%, the run ends, and you fail.
2. Waves and Debuffs
Every wave you clear earns you 1 to 4 Crystal Coins, and higher luck stats help you earn more per wave. After every 5 waves, a boss spawns with a chance to drop the Anti-Magic sword, Demon Wings accessory, or the Demon Dweller title.
Each new level also applies a random debuff, like reduced ability damage or longer cooldowns, so things get harder the further you go.
3. Restarting a Run
If the crystal gets destroyed, you get a prompt to restart. Restarting costs 1x Crystal Key. You can also turn on auto-spawn from the settings and type in the wave number you want to reset at, which is useful if you are AFK farming.
How to AFK Crystal Defense in Sailor Piece
AFK farming Crystal Defense is completely doable, and plenty of players are doing it right now. Here is the best setup:
The Ice Queen is currently the best option for AFK Crystal Defense. The ability has a massive range and a short cooldown, which means it can wipe out entire waves before enemies even get close to the crystal. The World is also a great fighting style option because it can push enemies back, which is especially helpful during boss waves with high HP.
If you want to do AFK farming, here are the steps to follow:
- Enter Crystal Defense and load into the mode.
- Let yourself lose on the first run to unlock the auto-restart option.
- Turn on auto-replay and set it to restart at whatever wave you start struggling on. If you start losing on wave 60, set the reset to wave 50 to keep things efficient.
- Sit in the middle of the arena and let Ice Queen's ability handle the waves.
- Use an auto-clicker to prevent disconnection due to inactivity. On both PC and mobile, this keeps the session going without any manual input.
Crystal Defense Merchant NPC
Crystal Coins are only earned inside Crystal Defense, so every coin you get is exclusive to this mode. Here is everything available from the Crystal Defense Merchant:
| Item | Price (Crystal Coins) |
|---|---|
| Common Chest | 1 |
| Rare Chest | 5 |
| Dungeon Key | 3 |
| Boss Key | 3 |
| Trait Reroll | 4 |
| Race Reroll | 4 |
| Tower Key | 8 |
| Clan Reroll | 9 |
| Epic Chest | 12 |
| Bloodline Stone | 14 |
| Legendary Chest | 25 |
| Mythical Chest | 65 |
| Secret Chest | 500 |
| Clover Outfit | 850 |
| Aura Crate | 1,000 |
| Cosmetic Crate | 1,400 |
| Destroyer Aura | 2,000 |
| Anti Magic Sword | 5,000 |
Sailor Piece Crystal Defense Stat Upgrades
Next to the Crystal Merchant is an Upgrade NPC where you can spend Crystal Coins to boost your stats permanently. Here is the full upgrade table:
| Stat | L1 | L2 | L3 | L4 | L5 | Total Cost | Max Bonus |
|---|---|---|---|---|---|---|---|
| Damage | 850 | 1,150 | 1,500 | 2,000 | 3,000 | 8,500 | +25% (+5%/level) |
| Critical Damage | 850 | 1,150 | 1,500 | 2,000 | 3,000 | 8,500 | +15% (+3%/level) |
| Critical Chance | 850 | 1,150 | 1,500 | 2,000 | 3,000 | 8,500 | +5% (+1%/level) |
| HP | 600 | 750 | 1,000 | 1,250 | 1,750 | 5,350 | +37.5% (+7.5%/level) |
| Luck | 1,250 | 1,750 | 2,250 | 3,000 | 4,250 | 12,500 | +15% (+3%/level) |
Crystal Defense is one of the best endgame activities in Sailor Piece right now. If you can set up an AFK farm, you can actually have the Crystal Coins stack up over time. Once you unlock the Anti-Magic Sword and max out your stats, you will have a strong advantage across the rest of the game.
 For more codes, tips, and info about the game, check out our dedicated Sailor Piece wiki.
