Permeable Form and spells casting

[Zhepna]

Hi,

If I cast Permeable Form and persist it, I understand that I can cast spells that don't attack while Permeable Form is active but I wonder if they affect the creatures the same way. Like, if I cast Glitterdust, since I'm incorporeal, does my spell can only affect incorporeal creature in the area?

[Kaleph]

Being incorporeal is not the same as being ethereal, and therefore you may influence normally other creatures that are on your same plane, irrespective of their corporeality. Lacking STR and other feats of beeing incorporeal do anyhow affect the way you interact with the physical world, although this shouldn't in most cases influence your spells.

If glitterdust interrupts the spell, instead, is another story. A spell like glitterdust is considered an attack when, for example, assessing if it interrupts an invisibility spell, so a reasonable DM ruling could extend this criterium to permeable form as well - but YMMV.

[Psyren]

Yeah, you'd have to determine if "attack" here means attack roll, or if it uses the broader invisibility definition which boils down to "offensive action." Either way, something indirect like summoning should be all right.

[Anthrowhale]

An illumian using persistent swift invisibility and persistent permeable form to function as a guardian spirit could be an interesting character concept. No direct offensive action is allowed, but there are many indirect actions available.