Another question of race.

[Theian G. Makarn]

So Aiergans were once humans that apparently died but held onto their will to live... or something like that. Oblivitans are the same, but they do not retain memories...

Does that mean that any human can become an Aiergan, or is it only Aelrans?

[Twilight]

This is an old question, but oh well.

Only Aelrans can become Aeirgan. They're already basically Aiergan who can't travel between planes and who are more fragile. Normal humans are just normal humans, unless they're Seers.