Walls can be placed randomly on the playground, They never contain a mine and can not be opened by clicking. Walls that surround the playfield can optionally be displayed. Both surrounding and internal walls can be opened as an option to make the game easier. Adding internal walls without opening them will however make the game more difficult as the information on adjacent bombs is hidden for those cells.

Shields assure that bomb explotions are never harmful! When the player opens a cell that contains a bomb he will only loose a shield. So if you make a silly mistake you can still continue the game even though you won't be braking any records. When the player is out of shields he can not continue play and the game is lost. A new game will therefore always start with at least one shield. The player can also choose any fixed number of shields or select them as a percentage of bombs on the gamefield.