While you’re completing The Rising Tide DLC Expansion, you’ll eventually gain access to an Optional Quest called What Ails You. Completing this quest will earn you the Adder Stone reward. This curiosity will allow you to locate and track down Aquamarine material as you travel through Mysidia.

Once you have the Adder Stone in your possession, Aquamarine stones will be illuminated and will begin making noise when you get close to them to help you find them. You can use these Aquamarine materials to create four custom accessories at the Haven Foundry:

Crafted Item	Materials
The Serpent’s Wonder (Deluge)	Aquamarine (x2) Ageless Tallow
The Serpent’s Word (Cross Swell)	Aquamarine (x2) Ageless Odorament
The Serpent’s Watch (Abyssal Tear)	Aquamarine (x2) Ageless Oilstone
The Serpent’s Worth (Tsunami)	Aquamarine (x2) Ageless Millet

As you can see from the materials list above, you’ll need to track down all eight of the Aquamarine stones to craft all eight accessories. You’ll also receive the Serpent Ring Design Draft as a reward from the quest, which will outline all of the materials you need.

Action/Story Mode vs. Final Fantasy Mode

As noted in the Tutorial Message for the Adder Stone, “Aquamarine is hidden throughout Mysidia, so be sure to check every corner of the region; but please note that some aquamarine locations will differ between Action/Story Focused Modes and Final Fantasy Mode.”

Action/Story Mode Locations

Final Fantasy Mode Locations