Chapter 6 of Earthopolis: A Biography of Our Urban Planet discusses the “realm of consequence,” the oscillating space occupied by life-destroying impacts of our city-enabled actions and habitats. In addition to forms of destruction generated solely by “endogenous” forces of political violence and war and by “exogenous” natural forces emanating from the Sun and Earth, the chapter explores places where our own city-enabled actions and impacts caused natural destruction, partly accounting for moments when urban worlds and the human population retreated in size. Cities incubated disease more prolifically than villages, resulting in many city-destroying and multi-continental pandemics. Expansions of agriculture to feed cities, the wider use of wood as fuel, and the resulting deforestation also had often city-destroying consequences via soil degradation and rising levels of river-water and silt. Urban industry and food systems, especially rice production, expanded human emissions of smoke and greenhouse gasses to Earth’s atmosphere as a whole for the first time during pre-modern times.