Ecumenopolis, the world city. Science fiction is full of them, from Trantor to Coruscant. But then it all stops working. What happens to a world of 40 trillion people when the food shipments stop and the lights go out? Post-apocalyptic mutants, aliens, freaks, weirdos, dangers, and wonders abound.
This expansion is playable using the rules for HERO System 6th Edition.