So my team - generally all around 15th level - and I are trying to sneak into a formerly drow citadel in order to snap off the big climactic battle and save the world. A frontal assault is not an option, and it occurred to me that this is a perfect opportunity to use my Druid's Animal Shapes spell. turning into a group of Bats might be a good, inconspicuous option, but I was wondering if there were any small or medium magical beasts that are able to burrow in stone? I've never really had much call for magical beasts in my experience playing this druid, so my normal roster of forms is lacking.
A pitty I can't use Vermin shapes. Spiders would be ideal.
Well, not that a druid can cast it, but if you have someone who can cast elemental body you could turn into earth elementals and just earth glide yourselves there.
I think dire badgers can tunnel through rock. Kinda big though.