A gaming machine provides an operation unit, a display unit, and a control unit. The display unit displays a display area with a plurality of cells in a grid. A respective symbol, from a set of symbols, is displayed in each cell. The symbols in the set of symbols having a ranking from lowest to highest and include first and second sub-groups. The symbols in the second sub-group of symbols have a higher ranking than the symbols in the first sub-group. The control unit randomly selects one of the symbols from the second sub-group of symbols. The selected symbols from the second sub-group of symbols and the first sub-group of symbols forming an instant sub-group of symbols. The control unit being further configured to randomly select a plurality of symbols associated with the display area from the instant sub-group of symbols.