; A dangerous crack is starting to form on the floor. You will have to find another way. [The cave shudders from some imbalance.] : Think it is caused by undermining previous tile mined above. No fix, though mining another wall, and therefore changing tunnel direction, worked on same tile.
; Another tunnel is too close. It would collapse. : Occurs when opening a new tunnel from the surface. Caused when there is already a mine underneath tunnel to the back or the sides of the entrance tile you are trying or if a tunnel is ahead but to far down to connect to tunnel into.
; 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 you are mining on will break out to the surface, but the surface is not exposed rock. To excavate it, you must first expose the rock on the surface.