Nightmare Weaver + Eclipsed Spell

[HedwickTheWorldly]

I have a question about if/how Nightmare Weaver and the Metamagic Feat Eclipsed Spell work together.

The relevant text (emphasis mine):

Nightmare Weaver wrote:

Benefit: By spending a full-round action to cast darkness, you can also make Intimidate checks to demoralize all foes in the spell’s initial area.

Eclipsed Spell wrote:

Benefit(s): Only spells that create areas of light or darkness can be eclipsed spells. If the eclipsed spell creates an area that shines like a torch or raises the light level by one step, you can choose to have the spell lower the illumination level in the affected area by one step, functioning like darkness.

If I were to play, say, a Karmic Monk 1/Heavens Shaman X, could I use Nightmare Fist/Weaver in the area of an Eclipsed Dancing Lights? Could I use Dancing Lights to satisfy the condition of Nightmare Weaver, and Dazzling Display all day, without burning 2nd level spell slots?

[Meirril]

Going by RAW I'd say no. Nightmare Weaver specifies Darkness, and makes no allowances for other darkness effects.

Going by RAI I'd also say no, because Nightmare Weaver seems to be asking for a spell resources and extending a standard action into a full round action to grant a targeted area effect intimidate effect. What you're proposing is to substitute that second level effect with a zero level effect and a meta-magic that may or may not require a full round action (deepening on what sort of caster you are) before you attempt to further modify it with Nightmare Weaver.

Now if you possessed an item that created a darkness effect that wasn't constant I'd let you use Nightmare Weaver with it, but the activation would still change a standard action into a full round action just as Nightmare Weaver describes.

Now on the other hand, I can see Unchained Rogues that want to be snipers taking the Eclipsed metamagic feat just so they can learn a zero level darkness spell.

[HedwickTheWorldly]

Fair enough. I figured it was too good to be true. Still makes for a fun trick to pull out of a hat for an Unsworn Shaman, for example, who can change their metamagic feat daily.