Completing the Infinity Domain Mastery quest in Sailor Piece is a must for players with the Strongest of Today fighting style. Doing so unlocks the powerful ultimate move for the style, which deals the most serious damage among other moves. You must submit certain items to an NPC after obtaining the Strongest of Today fighting style to complete the Sailor Piece Infinity Domain Mastery quest. This article provides a complete guide.

Completing the Infinity Domain Mastery in Sailor Piece

Completing the Sailor Piece Infinity Domain Mastery quest unlocks the "F" move for the Strongest of Today fighting style. So, you must possess the fighting style to receive and complete the quest. Here are all the steps involved in completing the Infinity Domain Mastery quest:

1. Obtaining the Strongest of Today Fighting Style

You must interact with the Strongest of Today NPC on the Shinjuku Island and submit the required items to learn the fighting style. Here is the list of items and how to obtain them:

Required ItemsHow to Get
1 Infinity Essence0.65 to 0.9% drop chance from the Strongest of Today boss
3 Blue Singularity2 to 3% drop chance from the Strongest of Today boss
9 Reversal Pulse15 to 25% drop chance from the Strongest of Today boss
Consume 6 Six Eye6 to 8% drop chance from the Strongest of Today boss
Strongest Sorcerer Title1 to 1.5% drop chance from the Strongest of Today boss
(Pity at 125)

The Strongest of Today boss spawns on the Shinjuku Island. Once there, interact with the Strongest Boss Summoner NPC. Then, use 1 Limitless Key to spawn the Strongest of Today boss. Given the drop rate of the required items, you might have to fight him multiple times.

2. Completing the Infinity Domain Mastery Quest

After obtaining the Strongest of Today fighting style, you must submit specific items to the Infinity Domain Mastery NPC to complete the quest. You can find the Infinity Domain Mastery NPC on the Shinjuku island. He is located inside the crooked building, which is near the Quest NPC of the island.

Here are the items required to complete the Infinity Domain Mastery quest:

Required ItemHow to Get
Infinity Trait- Use Trait Reroll currency to get the Infinity Trait
- It is of Mythical rarity with a drop rate of 0.25%
3 Blue Singularity2 to 3% drop chance from the Strongest of Today boss
1 Infinity Domain ShardCraft at the Infinity Domain Shard NPC

Follow the steps below to craft the Infinity Domain Shard:

  1. Farm 6 Energy Shards. You can obtain it by defeating the Strong Sorcerer enemy mobs on Shinjuku Island.
  2. Farm 2 Cursed Flesh. You can obtain it by defeating the Strongest in History boss on Shinjuku Island. Summon the boss with a Limitless Key by interacting with the Strongest Boss Summoner NPC. There is a 0.65% to 0.9% chance for a Cursed Flesh to drop.
  3. Find the Infinity Domain Shard NPC. He is located near the rock behind the crooked building with the Infinity Domain Mastery NPC (shown in the picture below).
  4. Submit 6 Energy Shards and 2 Cursed Flesh to get one Infinity Domain Shard.
Infinity Domain Shard NPC

After submitting the required items to the Infinity Domain Mastery NPC, you'll unlock the "F" move for the Strongest of Today fighting style. Additionally, you'll also receive a 30% permanent damage boost.

That's how you complete the Sailor Piece Infinity Domain Mastery quest. Follow our Sailor Piece wiki for more such in-depth guides and information about the experience.