Reduce person abuse

[Darrin]

I'm not sure that there is a hard and fast answer for this, although Invisibility offers some clarification, at least as far as what counts as an attack for the purposes of Invisibility.

I'd look at all the different ways you can harm your enemies without violating the definition of an "attack". Summoning other creatures to attack for you, for example, is one of the classic ways to abuse invisibility. Conjuring ice beasts and using their no-save "cold aura" for example can be a good way to "blast" your enemies with damage but without actually attacking them directly.