Octopath Traveler 0: All Crested Key Locations and The Eight Sacred Treasures

When you first boot up Octopath Traveler 0, one of the 'Belongings' you can assign to your created character is a Crested Key, described as A key engraved with the crest of a dagger. This is actually one of eight such Crested Keys found in the game — one for each main weapon type — and ties into a high level game-long quest. This is similar to how a Letter Fragment collectable can also be obtained as a Belonging right at the beginning of the game.

If you have this (or any other) Crested Key in your inventory, then a quest An Encounter with Viator will appear in the town of Valore. Here you'll recruit Viator — one of the game's many travelers — to your team, and he'll remark about finding the rest of the Crested Keys to find The Eight Sacred Treasures.

After you obtain the boat — the Queen Orsa — after the main quest The Rings Sealed Away, a new side-story quest appears titled 'The Eight Sacred Treasures'. This is a level 60 quest that you can receive well before you are level 60. It'll take you to an Outersea island called "Isle of Heroes Past". Here, you can use your Crested Keys to obtain the Eight Sacred Treasures. However, you'll need to defeat a high-level boss 'Warbringer's Phantom' before you can collect your rewards. Chances are you'll need to sit on this quest for a bit before you are able to defeat it.

Once you have beaten Warbringer's Phantom, you can collect the eight legendary weapons, one of each type, provided you have the Crested Key for it. We've listed the eight Crested Key locations down below.

While these aren't the absolute best weapons in the game, they are still worthwhile to obtain to outfit your party:

• Storm Blade
• Deathclaw Dagger
• Tempest Spear
• Spirit Axe
• Moonlit Bow
• Evenfall Fan
• Solaris Tome
• Staff of Discipline

Octopath Travler 0 - Crested Key Locations