Edge:State Of Decay works because it takes the clichés of zombie fiction – clashing survivor personalities, scavenging for supplies, roaming hordes, infested houses, amateurishly fortified safehouses – and successfully translates them into a set of intersecting systems and rules. Sometimes these rules seem arbitrary. Scavenge too quickly through houses for supplies, for example, and you might, somehow, make such a racket while rifling through a backpack that a crowd of nearby undead draws near. At other points, they integrate beautifully, such as when your attempt to clear out an infestation that’s affecting the morale of your safehouse alerts a nearby horde. The game never judges you, offering no morality system despite the frequent dilemmas and difficult choices its systems organically generate. But it certainly tests you. This is as close as we’ve come to putting our lazily daydreamed zombie survival plans into effect.