Of late, Eilistraee is now counted among the Seldarine and her divine realm has moved to Arvandor among the other elven deities. I'm not sure her old domain in the Demon-Web Pits even exists anymore.
Downside of this is its going to make it more difficult to reach out to the drow still under Lloth's thumb since it feels like that'll make it easier to keep her influence and call away.
At the moment, the Seldarine / Lloth-sworn difference doesn't make much sense because there's apparently neither much difference in mechanics (0 difference) or narrative (seems to be the same sort of dialogue).
I kind feel that if Seldarine Drow were renamed "Apostate Drow" or something similar...it would make more sense even if it wouldn't be especially accurate given what the actual definition of apostate is.
Oh wow, you're right. How did I miss that. That's odd though, since - as you say - it kind of distances her from her people she wants to lead to "goodness"...
I was initially opposed to "apostate", but maybe it would be a good counterpart to Lolth-sworn. Then again, there's also grey area between the two.
