If it helps, the Garleans use such methods because they cannot use magic and so dampening their own non-existent ability to use it isn't really a factor.
So, considering that we're dealing with characters that can externalize their aether via magic... maybe some protective spell woven into a piece of jewelry? One that helps to deflect magic that goes their way? I mean, in a spellcaster-vs-spellcaster battle, I'd assume that there's got to be some manner of protective wards and spells that one uses to reduce the incoming magic damage they're going to take.
In which case, the enchantments are going to be more important than the materials... in which case you can include some folklore fluff that actually has no actual weight. A belief that some material helps the process when it's actually just the magic that matters.
Alternatively: materia. You use materia to strengthen armor in the Armorsmithing quest chain. And there's certainly a wide selection of materia that protect against certain elements. So maybe some manner of jewelry socketed with the appropriate materia might be the way to go.
So, considering that we're dealing with characters that can externalize their aether via magic... maybe some protective spell woven into a piece of jewelry? One that helps to deflect magic that goes their way? I mean, in a spellcaster-vs-spellcaster battle, I'd assume that there's got to be some manner of protective wards and spells that one uses to reduce the incoming magic damage they're going to take.
In which case, the enchantments are going to be more important than the materials... in which case you can include some folklore fluff that actually has no actual weight. A belief that some material helps the process when it's actually just the magic that matters.
Alternatively: materia. You use materia to strengthen armor in the Armorsmithing quest chain. And there's certainly a wide selection of materia that protect against certain elements. So maybe some manner of jewelry socketed with the appropriate materia might be the way to go.
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