 The player initially can see a top-down view of the surface-level of the fortress site; each layer of a z-axis level can be viewed when the player changes it.An entire underground level would be seen as its entire section of terrain while a mountain at the surface level would have only its section visible with the remaining surface landscape.Thus, for digging, the player can designate, for every z-level starting from the surface, staircases to be carved, and, at the final designated level, end the staircase by having it dug into a room.