Generations ago, the Surface became nearly uninhabitable and the surviving population split between two superstates — the Underground Sector, built into the earth below, and the Sky Sector, held aloft by alien technology no one fully understands. Those two superstates are now at war over resources and over what the future of life on the Surface should look like. The Sky Sector holds the technological advantage. The Underground Sector's answer is Miaobot Zero: a giant catlike mecha driven by a sophisticated AI, commissioned personally by the Empress. Almost no one in the chain of command knows why the Empress has taken such a specific and personal interest in this machine. The rumors about what connects her to it have not yet resolved into anything confirmed.