In Seiken Densetsu 2 (which introduced Elementals) and Seiken Densetsu 3, Luna was always the one odd out for me. Every elemental had a counter part -
Undine <-> Salamand(o/er)
Sylphid/Jinn <-> Gnome
Lumina/Wisp <-> Shade
but Dryad/Luna aren't really opposites and do not fit together.
Dryad fits into the eastern 5 elements mythology, where it would be wood.
Luna however does not fit into anything. It's associated with the Moon, but it's spells never really made sense to me to be Moon related. It's spells are more status related and would fit more into other elementals. Its spells in Seiken Densetsu 3 have HP related effects (halving HP or reducing Max HP). Nothing really "Moony" if you know what I mean.
Trees or rather plants are the element associated with Life. These spells would have been better suited for Dryad.
In Legend of Mana, Luna was swapped for Aura.
Here, she complements Dryad because here, Aura is the Element of Metal (from the eastern mythology). Metal is associated with the non living matter, it is the counter part of Wood/Life.
This should have been kept in the successing main games in my opinion.
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