; The cave walls sound hollow. A dangerous side shaft could emerge. [The cave shudders from some imbalance.] : Occurs inside a mine. This message appears when the tile being mined shares a single corner with an existing tunnel. To continue adjacent tiles must be mined out before mining can continue on this tile. See example on the right.
; Another The mountainside would risk crumbling. You cannot tunnel is too close. It would collapsehere. : Occurs when opening a new tunnel from the surface. Caused when there is already a tunnel to the back or the sides of the entrance tile or if a tunnel is ahead but to far down to connect to. Surface mine down to reduce the slopes, then attempt to tunnel again.
; The cave walls look very unstable. You cannot keep mining here. : Occurs inside a mine. Happens when mining close to the top of the rock layer. The ceiling of the newly mined tile would break the rock layer. Can sometimes be avoided by mining downwards or by lowering the mine floor and thereby opening the new tile a bit lower.
; The cave walls look very unstable and dirt flows in. You would be buried alive. : Occurs inside a mine. Happens when the tile being mined will break out to the surface, but the surface is not exposed rock. To excavate it the rock on the surface must be fully exposed.