Game Like a Statistician: The Sometimes-Filthy Opportunity Cost of Zing

Dragon Quest is a interesting franchise of games for a number of reasons: it’s got a very nationalized fandom (large in Japan, tiny worldwide), the cutest mascot, and it’s really damn good.* Of particular interest here is that the Dragon Quest franchise has, from very early on, incorporated a good deal of random chance. Owing to the creator’s personal interest in gambling, opportunities to press one’s luck are found throughout the franchise, both overtly advertised in casinos and more subtly worked in the battle system. Unlike in real life, the casinos in Dragon Quest are eminently beatable – save at church, play highest-stakes game available, reloading if necessary, until a win happens, and repeat until you have the Metal King Sword at level 8. The finer points of DQ’s battle system are less obviously solvable – information beyond one’s control can determine whether a risk one is about to take is smart or stupid, and a lot of fictional parties ended up dead thanks to their players inadequate assessment of said risks.

One of the most fun choices in the series originates from a spell introduced in the series’ third installment. Zing is a spell which, half of the time it is cast, does nothing, an annoying feature balanced out by what it does the other half of the time – resurrect an unconscious party member. Thus, for much of the game, a player with a KO’ed ally faces a nonsimple dilemma – is zing generally worth it? Does the upside of having that ally back outweigh the opportunity cost? I’m going to examine some of the fundamentals of that question using a fairly basic battle simulator I built from scratch.

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