So this question is to do with a character I'm playing as and her role moving forward. She is a Drow, with the first Drow Nobility (Advanced Race Guide) feat, and will likely be taking the Improved and Greater Drow Nobility feats as well progressing. This however changes her Darkness spell to Deeper Darkness before it get's any additional casts per day.
So the question is, does Deeper Darkness count for taking the Nightmare Weaver (Ultimate Combat) feat?
Reading as written, and considering the book release dates for Ultimate Combat and the Advanced Race Guide which contains Drow and the Drow Nobility feats, I could take it either way? Ultimate Combat came out first, and Deeper Darkness is a PHB spell, so it's not like Deeper Darkness wasn't an option for Nightmare Weaver, however Deeper Darkness reads as 'functions as darkness', so it may have been considered at the time. Advanced Race Guide being released after UC, may have made the change for Drow to have Deeper Darkness as to avoid the synergy of Nightmare Weaver with Greater Drow Nobility having an at-will Intimidate bomb with 20ft(Darkness)/60ft(Deeper Darkness) as a full-round action. Though by that same regard, Dazzling Display (PHB) is exactly that, and released before, though is 30ft flat, and isn't also casting Darkness.
So I guess the question is twofold. Does Deeper Darkness as an ability count for taking Nightmare Weaver? And if not, if you had Darkness and Deeper Darkness, would Deeper Darkness (which functions as Darkness) be usable with Nightmare Weaver?
As written, no to both. Deeper Darkness is not Darkness—the “functions as darkness” is rules shorthand. On the other hand, if your GM is nuts enough to let you play a Drow in the first place, you could probably make the case for allowing it to work that way. Also, just as a note, be sure to pick up “see in darkness” somehow, otherwise you’ll be blinding yourself when you turn off the lights.
No, and even if it did the feat wouldn't do you any good when casting deeper darkness.