Craft it
You need
Make it at (any of these)
Needs a Pal with Handiwork. Best:Solenne (Lv 8), Selyne (Lv 7), Wistella (Lv 6)
Work: 300
A bone flute recreated by deciphering a Faded Schematic. Its clear tone, echoing endlessly beyond the horizon, will likely call forth the oath-keeper, the Legendary Ocean King.
You need
Make it at (any of these)
Needs a Pal with Handiwork. Best:Solenne (Lv 8), Selyne (Lv 7), Wistella (Lv 6)
Work: 300
Keep one of these schematics in your Inventory or in a chest at your base to unlock crafting Echoing Flute at that tier and rarity.