Can incorporeal creatures cast spells from within walls?

[Ravingdork]

Incorporeal trait (truncated) wrote:

An incorporeal creature or object has no physical form. It can pass through solid objects, including walls. When inside an object, an incorporeal creature can’t perceive, attack, or interact with anything outside the object, and if it starts its turn in an object, it is slowed 1.

Can a ghost mage go inside a wall and then cast cone of cold or use telekinetic assault?

Area effects such as those don't have to deal with flat checks for concealment, don't have the Attack trait or an attack roll, and don't require an interact action. That means no rules have been violated, right?

Still, I find it unlikely that the developers would create a monster that could never be targeted, but could telekinetically assault anyone in the area endlessly and with impunity.

[Guntermench]

I don't think you'd have Line of Effect from inside a wall.

[shroudb]

Line of effect is still a thing.

[Perpdepog]

The words "perceive, attack, or interact..." aren't capitalized, either, which suggests they're using a general usage rather than a specifie bit of rules language. Casting spells is still interaction with things outside of the wall even if it's not specifically targeting someone.

I guess a ghost could still hide in a wall and buff themselves though.

[Claxon]

Yeah, I'd say you don't have line of sight or line of effect to anything but the wall or yourself.