PURPOSE: To prevent an overflow of start storage even in a regular game state, and also, to execute control at the time of starting a variable display, which is merit to a game store, as well.

CONSTITUTION: When the number of storage is under '2', a variable display time is set to 5.2 seconds (step S76), and in the case where the number of storage is large and ≥'2', the variable display time of a picture pattern is set to 2 seconds in the case where ≥4 seconds elapse from the start time (step S78). In such a way, in the case where the number of start storage is small, the variable display time of the picture pattern is lengthened, and image-up of a game store is realized by giving such an impression that start prize-winning is frequent, to a player. On the other hand, in the case where the number of start storage is large, an overflow of the start storage is prevented by shortening the variable display time of the picture pattern.