While it is a casting cost that isn't quanta, that does not make it "fake quanta" or a "pseudoquanta" (both require the Alternate Cost mechanic to expend real quanta).
Every element can afford to cast these cards so I would personally categorize them as Alternate Cost, Other (unless the card's specific mechanical theme would dictate otherwise) which fits the generic dragon theme IMO.
Your intent/goals seem to line up exactly with what I would expect from a Thematically Designed Alternate Cost series.
(The only difference from what you have now is standardized terminology and normal card backgrounds)
In summary:
Its cost is not quanta but still is a valid alternative cost (though strange and hard to balance
)
Its cost can fit thematically into Other or any Element if the specific card has a sufficient elemental influence. (
: Firebreathing: Deal 1 damage to target. Can be used multiple times per turn.) Shortbow's Air influence is not sufficient.
The Curators will probably still place it in the PseudoElement poll.
You might want to add reminder text about the Dragon Alt Cost for cards using this alternate cost along with another cost or ones that have room in the card text.
Ex: "You need [N] dragons to cast."
