It is important that you upgrade these structures whenever possible as they serve a lot of purposes and aid in your quests. Even at their starting level the structures you can use in the Sanctury are very useful for growth building and upgrading them boosts their benefits even more.
To earn upgrade the Sanctury Structures you need to gather all 12 Breaths of Orbis. Collecting these rare stones may require reruns on some stages to unlock additional areas in each region. Pay particular attention to the locations that have a white diamond-shaped icon beside it.
There are 12 Breathes of Orbis you can get from each story difficulty level and their locations are: 1-9, 2-S6, 3-S3, 4-S6, 4-S12, 5-S6, 6-S6, 7-S6, 8-S3, 9-S3, 9-S6, and 10-S3.
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