What Is Atomic Mastery in Sailor Piece?
With Update 7.0, Sailor Piece introduced a new progression system for the Atomic sword, and this is where Atomic Mastery comes in.
It is not just another questline. This is what unlocks the F skill of the Atomic weapon and boosts its overall damage, making it one of the strongest upgrades for players in mid to late game.
If you are already using the Atomic sword, skipping this is a big mistake.
How to Start Atomic Mastery Questline
Before you even think about starting the mastery quests, you need one thing cleared first.
You must already have the Atomic sword.
This weapon is obtained from the Atomic Trainer NPC by exchanging materials like:
• Shadow Remnant
• Eminence Essence
• Atomic Omen
• Around 45,000 Gems
Once you have the weapon, head to Lawless Island.
Go towards the left side of the island, move behind the large building, and walk toward the edge. That is where you will find the Atomic Master NPC.
When you reach him:
• Press E to interact
• Accept the quest
• Make sure you do not have another active quest
You can cancel and restart the quest anytime by talking to the NPC again, which is helpful if you want to reset progress.
SEE ALSO:
Sailor Piece Codes (March 2026) – Free Gems, Rerolls, and Rewards
Sailor Piece Warlord Race Guide (How to Get & Buffs Explained)
How to Get Sukuna V1 and V2 in Sailor Piece (Complete Guide)
How to Get Dismantle Fang in Sailor Piece (Fast Method)
All Atomic Mastery Quests in Sailor Piece
The Atomic Master gives you a 3-step questline, and you must complete them in order.
Atomic Mastery 1
Defeat the Atomic boss on Hard or Extreme difficulty 20 times
This is mostly a grind quest. If you have a decent build, you can farm this relatively quickly.
Atomic Mastery 2
Get the Eminence Clan
This is where RNG hits hard.
The Eminence Clan is a Mythical rarity, so you will need multiple Clan Rerolls. There is no shortcut here, only consistency.
Atomic Mastery Final
Reach Floor 50+ in Infinite Tower 5 times
This is the hardest part of the questline.
It tests your full build, including:
• Weapons
• Fighting style
• Accessories
• Overall damage output
If your build is not optimized, you will struggle here.
How to Complete Each Requirement Faster
The questline is simple on paper, but execution is where most players get stuck.
Here is how to make it easier:
For Atomic Boss Farming
• Use high AOE builds to clear faster
• Farm on Hard difficulty if Extreme feels slow
• Team up with players to speed up runs
For Eminence Clan
• Save Clan Rerolls instead of using them randomly
• Use codes to stack rerolls quickly
• Roll in bulk instead of one by one
For Infinite Tower
• Focus on survivability, not just damage
• Use strong swords or meta builds
• Learn enemy patterns instead of rushing
Atomic Boss Spawn Guide
The Atomic boss is not always available by default.
You need Abyss Sigils to summon it.
• Hard difficulty requires 3 Abyss Sigils
• Extreme difficulty requires 4 Abyss Sigils
Extreme gives better rewards, but it is significantly harder.
Rewards for Completing Atomic Mastery
Once you finish all three quests, you unlock:
• Atomic sword F move ability
• Around 30 percent damage boost
This upgrade is massive, especially for boss fights and endgame grinding.
Is Atomic Mastery Worth It?
Short answer yes.
If you are using the Atomic sword, this is not optional.
It improves both your damage output and combat efficiency, and without it, your build will always feel incomplete.
FAQs
Where is the Atomic Master NPC in Sailor Piece?
You can find the NPC on Lawless Island, behind the large building near the edge of the map.
Do Atomic Mastery quests have a time limit?
No, you can complete them at your own pace.
How hard is Infinite Tower Floor 50?
It is one of the toughest challenges in the game and requires a strong build and proper strategy.
What does Atomic Mastery unlock?
It unlocks the Atomic sword F move and increases its damage by around 30 percent.
Hi, I’m Ankit Kumar, the founder of StealthyGaming. I handle everything from SEO to researching and writing gaming articles. I’m passionate about helping fellow gamers stay updated with the latest tips, guides, and news. When I’m not optimizing content, I’m probably testing out new games or digging into strategies to make my articles as helpful and engaging as possible.