Dryads (Woodmen and the like...) aren't exactly immune to Earth magic. In fact, it heals them.
I checked the Brave Story record, 'Delita's Thoughts', where Ramza and Delita have a chat in Zeltennia Church. There are 3 other unnamed parishiners in the church. :meditate:
Question: What is the only item in the game that you can buy for 1 gil?
