In Final Fantasy Resonance, if you want to get the best out of your party member Fina, you need to find and convince Espers to lend their unique skills to you. Siren is one that you’ll pick up along the way, but most others will be completely optional, much like Carbuncle.
This Esper will only reveal themselves if you find all three Ruby Fragments hidden around Olderion. These can be a little tricky to find, but if you’re having a hard time, we can make things easy for you by pinpointing their exact locations.
Ruby Cave & All Ruby Fragment Locations

First of all, to begin this quest, or at least be aware of what the Ruby Fragments are for, you’ll need to head to the Ruby Cave, which is just north of the Sanctum of Firion, not far from where your Airship crashes.
Head inside and inspect the gravestone, which will send you on your way tasked with looking for three Ruby Fragments.

The first isn’t too far from the cave, as you’ll find in the south-east of the island, near two small bodies of water not far from the Rukh Cave.
The second Ruby Fragment is located on the east coast of the island. You’ll want to hug the island’s edge, and you’ll find the Ruby Fragment laying around. If you hit the Sanctum of Squall, you’ve gone too far.

Then lastly, you have the Ruby Fragment located on the west side of the island. You’ll want to cross the water as if you’re heading out toward the Secluded Dwelling and the Sanctum of Tidus. But then, head toward a little hill on the left side of the entrance to Waterfall Way, and you’ll find the final Ruby Fragment.

After you find all these Fragments, you simply need to head back to Ruby Cave, and unlike most other Espers, you won’t need to fight Carbuncle to have them offer their services.

