At first citizens were fascinated to see how, when one automaton began to move a heavy beam or a plate of glass into position, others would be drawn to assist. It had been an acknowledged triumph for biomimetics—unlocking the behavioural code of Amazonian nest-building ants. The automata, the size of a small dog, with carapace and musculature modelled on ants, were produced by fiercely competitive corporations in rival cities. After tweaking the code, cohorts of the automata, known as bildants, engineered adobe houses to specification. Incorporating rocks, bricks, wood and glass, bildants constructed novel dwellings, as complex as termite mounds. Imitating tradesmen—omnipresent, constantly testing the integrity of their structures—they became more like us. In parallel, humans gradually adopted the behavioural traits of the bildants.

But who were the conquerers? What weaknesses passed on?
It was a golden age; there was great harmony within the city.
That was before the war.