To provide a player with expectation for whether or not a forenotice performance continues in each variation cycle and bring his/her attention to a result of an interim variation cycle.

In symbol combinations displayed in first to third variation cycles (symbol variation games) with continuous performances, a symbol combination displayed on a valid line L5 formed by connecting symbol display positions H4, H8, and H12, or a valid line formed by connecting symbol display positions H6, H8, and H10 may be found to be valid in some cases. Consequently, a player pays an attention not only to a final variation cycle with the continuous performance but also a result of an interim variation cycle such as what kind of symbol combination is displayed in the interim variation cycle.