I recently discovered one new game-breaking bug:
- After the party has obtained the Cell Key in Fantasma Cavern, some of the cave passages in the outside area can't be used until the party has freed Tommuz and Yrana. This also applies to the cave passage left of Fantasma Cavern that leads to a treasure chest which contains an HP Increase. Unfortunately, you mixed them up and made the left cave inaccessible, not the right cave near (left of) Fantasma Cavern. That means: If the player obtains the Cell Key in Fantasma Cavern and then goes through the cave passage left of Fantasma Cavern before freeing Tommuz und Yrana, they will get permanently stuck, since the way back is blocked.