Digging while Invisible

[Quidam]

I had recently been considering a spell that digs when I found one in Spells & Spellcraft- Dig. I was intending on using it to dig forty foot pits under the feet of my enemies. Of course, that only works when you're on earth, but still- could be fun.

Now, here's the question: if one were invisible when casting it, do you reappear? I'd think not, as, even though the affected area is directly underneath your foes, they are not within it when the spell is cast and therefore you stay invisible.

Sound reasonable?

 

[Dursk Starkfire]

I'd say no, you do not appear. Dig doesn't sound to be an offensive spell, and you only appear from invisibility when you physically attack or cause damage. However, your enemies would be able to discern your general location from all that verbal casting you're doing.