The Mirrors of Soleanna, which are located throughout the town, city, and the forest of Soleanna, are shrines that hold large circular mirrors that appear to be magical. Instead of a reflective surface, they each show places of Soleanna that cannot be accessed by casual means. They also work as portals to those locations. They usually require a specific upgrade or story progress for them to be reached.
They are the access points from Town Stages to the Action Stages. When touched (or at least homed into) the Action Stage will begin for the player to progress through.