A gaming machine (10) has a display (14) and a game controller arranged to control images displayed on the display (14).The game controller is arranged to play a game (16) wherein at least one random event is caused to be displayed on the display (14). If a predefined winning event occurs, the machine (10) awards a prize. When a special symbol is carried by a symbol-carrying element into a display position on the display (14), the special symbol substitutes as more than one occurrence of a standard symbol of the game (16).