FEED Magazine
FEED Video Games 2001: Guinea Pig of Death
Steven Johnson on the notorious killer-rodent mod for The Sims

In the early spring of 2000, Maxis released a new downloadable mod for their best-selling game, The Sims. For the price of a quick file transfer, Sims players could add an adorable guinea pig, complete with cage and training wheel, to their onscreen households. Maxis had already released a few new objects by the time it unleashed the guinea pig, and hard-core players were already familiar with how a new download could bring new joy into Simsville -- sometimes triggering exclamations of delight from the virtual characters -- and so when the guinea pig appeared on the Maxis site, thousands of gamers immediately transferred the file to their hard drives. And sure enough, the guinea pig quickly became a popular attraction in their onscreen households -- the Sims would stop by and play with the adorable little critter, while the more meticulous Sims would take the time to clean out its cage. Occasionally, the guinea pig would bite the hand that fed it, but after a quick reflexive gesture, the Sims seemed unharmed by the attack.
Until they started to get sick.
The symptoms first started appearing on the Maxis bulletin boards and other Sims fan sites, related by bewildered players: first a persistent cough, then a loss of energy. And then a one-way trip to the SimCemetery. The novelty of the symptoms were the first point of discussion: Sims had died before, but they'd never had a cough before -- something in the game had changed, though the culprit wasn't clear. A game that had begun life as a twenty-first-century dollhouse suddenly seemed like a Richard Preston book. Something was killing off the Sims, but where was the infectious agent coming from? After countless bulletin board posts, the Sims community finally detected a common pattern: Players who had downloaded the guinea pig add-on, but failed to keep the cage clean, were succumbing to the disease. Shortly thereafter, Maxis admitted that it had deliberately included a virus in the guinea pig, and released a non-lethal version.

While the guinea pig was not a user-created mod, it showcased an important attribute of The Sims' semi-open architecture. At first glance, one of the things that makes the game so compelling is the fact that the characters onscreen respond coherently to the world that surrounds them. Let one of your Sims buy a pool table, and his lifestyle changes accordingly -- he has more fun playing, of course, but he also spends a little less time reading or practicing the piano. Will Wright recognized early on that this sort of causality would be difficult to engineer if he wanted the game's architecture to remain open: How would the Sims themselves know how to respond to new objects inserted into the world? It's hard enough responding to the first sighting of a Furby or a Winnebago as a sentient human being -- how is a digital life form supposed to figure out what to do with such things?

Wright hit upon a brilliant -- and vaguely McLuhanite -- solution to this bind: Rather than struggle with teaching the Sims how to learn, he built intelligence into the objects. According to the game's underlying model, objects in the world -- an Aston-Martin, a Furby, a Winnebago, not to mention the more prosaic goods that come bundled with the game -- are endowed with a set of expectations about how a virtual human will interact with them. When a given Sim enters into the force field exuded by an object, those expectations start to shape the behavior of the Sim. If one of your onscreen citizens walks into a room with a television in it, there might be a fifty percent chance she'll sit down and stare into the screen hypnotically. Technically speaking, that's not because your character herself is prone to zoning out in front of the tube -- it's because the tube itself has been programmed to trigger zoning in half the Sims that come into contact with it.
The guinea pig exploited the fact that these objects can trigger both primary and secondary behaviors: When players integrated the furry rodent into their games, their characters immediately started showing the primary behavior of playing with the guy and cleaning his cage. The behavior of getting sick came later, but it was also built into the guinea pig object. Effectively, the guinea pig was a vehicle for Maxis to introduce sickness into the Sims world without having to put up a blurb on their Web site saying "download the Ebola patch here." It was a Trojan horse delivery mechanism for a virtual virus. And if Maxis was capable of such malevolence, imagine the carnage that might ensue if object-creation became a more democratic process. While early announcements for the Sims promised that users would be allowed to create new objects -- and thus new behaviors -- for the game, Maxis has been extremely proprietary about the object tools, allowing players to trade characters or houses or decorative elements, but not allowing them to create new behavior types. The killer guinea pig may have been a warning to those players clamoring for an even more open architecture: Be careful what you wish for.

Steven Johnson is FEED's Co-Editor-in-Chief and the author of Interface Culture: How New Technology Transforms the Way We Create and Communicate.

NEXT: Wagner James Au on the constantly expanding story of Thief's hero, Garrett

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