From publisher's description: "The sun’s gone weird and sullen. Broken monuments to forgotten glory lay strewn across and buried beneath the ever-changing face of the endless desert. Savage and desperate, merciless predators stalk sand and shade. Ancient now, the newest cities crumble; time laughs; indifferent, extinction continues. BX mars is a science fantasy setting supplement for old school games. Five new classes, a complete setting, over a hundred illustrations and maps, maps, maps!"