; Dirt will flow in. : Occurs inside a mine. This means the tile you are mining is very close to the surface. It would ordinarily create an entrance, but the rock layer on the surface has not been uncovered. If you dig up the dirt on the surface above the tile, further mining will create a cave entrance (or exit, as it may be.)
; A dangerous side shaft will appear. : Occurs inside a mine. This message appears when the tile you are excavating shares a single corner with an existing tunnel. To excavate it you must first excavate so the target tile shares an entire wall with the other tunnel. See example on the right.
; The cave walls look very unstable. You cannot keep mining here. : Occurs inside a mine. This means the tile being mined is adjacent to a cave entrance, and cannot be opened. There's nothing to do about it, except wait for that entrance to collapse.
== Ore veins ==