"I have this wand left over from that foul man we fought in the moathouse -- I could make us all invisible as we enter, at least we would be hidden from sight, but not from sound...."
"Alternatively, we could send a scout ahead, who is somewhat sneaky and quiet, to take a quick look and then report back -- all of this hinges upon how one gains entry to the mine system -- if there is just an opening without a door, that is easiest. But if there is a large door or gate, then all bets are off, as how can you sneakily open a giant gate?"