Occasionally, when I pause They Are Billions and zoom out on my tightly packed, grid-based steampunk settlement, I think about how the tiny families in the centre could have just as easily lived their entire lives without ever seeing a single zombie. There s little in the way of a fixed story or characters in this survival strategy, either in its separate challenge maps or ambitious, flawed campaign. But there is a constant mood of melancholy, darkening the air like industrial smog; the uneasy feeling humanity died out a long time ago. As the saying goeth, you either watch your settlement get munched to bits by zombies, or you live long enough to continue colonising hell to extend the borders of a grim dystopia. Jolly good, then.