If no RAW is available, I'm curious what PFS treats the RAW as.
If this isn't something that's ever been clarified anywhere (though I'm assuming somewhere it has, in all the FAQs/erratas/Dev comments), maybe I can get some FAQ hits on it, as for balance table-to-table reasons it seems like something that needs an answer.
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A caster puts up a Wall of Stone, using we'll say Shades.
Enemy goes to hit it (I know "interaction" has some discretion, but I think most would agree hitting something is interacting with it)
Enemy makes the Will save, realizes it's an illusion/shadow.
Which applies...
A) The enemy has an 80% chance of hitting the wall, and a 20% chance of going right through it as if the wall wasn't there (Is that per turn he rolls the %? Or for the duration of the spell whatever he first rolls is always applied?)
or
B) To that enemy, the spell only has 80% the HP/hardness of a real Wall of Stone to that foe. (I'd assume in that case for the duration of the spell, but what happens if that enemy and an enemy that failed their will save are both wailing away at the wall?)
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It looks like (B) would make the shadow spells much nicer, as you could depend on the spell always doing something, but (A) seems like it'd be easier to adjudicate for a GM. Since Shadow spells are described as quasi real I'd want to lean towards (B) as well, but from what little I can recall off my head I could easily be missing something.
I'm on the spot to answer this question as best I can, and I have zero PF materials with me at the moment to attempt to look it up.
The description of Shades answers this: "Nondamaging effects are 80% likely to work against nonbelievers."
The description of Shades answers this: "Nondamaging effects are 80% likely to work against nonbelievers."
Gracias, that's what I needed.