The proposal I have in mind is that due to how unambiguous alien forms as a concept are, is a lore tag that specifically describes said abstract creature as abstract_alien_(lore) (or something similar).
The best example of said abstract alien forms is probably from Neon Genesis Evangelion:
But I'm sure there might be other examples of abstract formed aliens.
The requirement for said tag usage would be that only characters that aren't original characters would be able to qualify as this would help janitor more easily determine if it's an alien character with an abstract form or just an non-living object/thing.
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