It should be noted that "modern day" Arcanima is a descendant of both Nymian Scholasticism (Scholaring? Scholology? Scholomancy? Scholomance?) and Allagan Summoning techniques. Which is why the base class can flow into either one from the advanced jobs from a lore standpoint. The Carbuncle, comparatively, is Arcanima's attempts at creating a Fairy or Egi. It's pretty primitive in comparison to the other two types.
If I recall correctly, a Fairy is actually a full-blown elemental rather than just an aetheric construct like a Carbuncle. The Nymians somehow managed to learn to create them - and the reason why you kind of need a soul crystal as a SCH is that creating new ones is a very lost art and the existing ones are bound to these crystals. So, unless you learned how to create a wholly new one or extract an existing one from a crystal by the Tonberries (which I suppose is an angle you could take since they're the transformed denizens of Nym and you already learn advanced Scholar techniques from one starting at level 50), there isn't going to be much of a way to just... summon one without a soul crystal.
If I recall correctly, a Fairy is actually a full-blown elemental rather than just an aetheric construct like a Carbuncle. The Nymians somehow managed to learn to create them - and the reason why you kind of need a soul crystal as a SCH is that creating new ones is a very lost art and the existing ones are bound to these crystals. So, unless you learned how to create a wholly new one or extract an existing one from a crystal by the Tonberries (which I suppose is an angle you could take since they're the transformed denizens of Nym and you already learn advanced Scholar techniques from one starting at level 50), there isn't going to be much of a way to just... summon one without a soul crystal.
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