The Cavern of the Stolen Fayth is an optional side quest area that you can visit once you reach the Calm Lands. They can be accessed by taking the valley pathway after the team defeats Defender X along the bridge.
The game does not require you to visit the Cavern of the Stolen Fayth, but the first time that you can access it is while traveling through the Calm Lands. Check out the Calm Lands section of the strategy guide for more information:
There are some side quests that can be completed in the Cavern. Namely, this is where you obtain the optional Aeon Yojimbo. Check out the side quest page for more information:
