A discharge lamp lighting apparatus has a configuration including a control unit which discriminates, for each polarity of an AC rectangular wave output, the output voltage detected with an output voltage detector for detecting the voltage applied to a discharge lamp, and carries out constant power control for each polarity separately. Upon a triggering of a bonus event, the gaming system generates, for each bonus event eligibility point accumulated for each player, a random number from a predefined range of numbers. The shut-off holding means maintains discharge shut-off condition after abnormal discharge shut-off by shorting or connecting a low resistance between the external plus terminal and the external minus terminal from outside of the battery pack.