Quote Originally Posted by nickl_2000 View Post
Does Meteor Swarm work underground?
AFAICT, nothing in the spell description precludes it.

Quote Originally Posted by NNescio View Post
Planar Bind/True Polymorph something with immunity to nonmagical attacks. Sic it on the human colony while you and your mates sip martinis and watch the spectacle with Scry-Teevo. Cackle evilly all the way.
Swap out immunity to nonmagical attacks with immunity to psychic abilities, and you've just solved the illithid problem, so I don't really think that changes the illithid vs. human colony math. Regardless, I'd put that in the out-of-box strategies I'd expect to see in these scenarios. It is really the...

Or, yannow, just Mirage Arcane the whole place. Or Shapechange/True Poly into a dragon (shadow for added !!FUN!!) and burn down the whole place, if you want to be hands-on for some reason. Remember to have a friend (or Sim) with Dispel if you go with True Poly.
...hands-on scenario like this that I think the OP was talking about (given that he was worried about the illithids' dominates and mind blasts).