I haven't used it, but the description says that it makes a game event occur.
You know how sometimes you get a package delivered to your door, or you get e-mail saying that you've overpaid or underpaid your taxes, or you win a prize for eating a lot of hot dogs, or there's a power failure and all your food spoils? (There are lots more than that, but that gives you a sense of the kind of thing I'm talking about.) I'm pretty sure that those things are game events. So buying a roll of the dice means that some game event will occur -- it could be positive or negative.
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Middle-aged professional woman still plays computer games. Film at 11.