At first glance, this layer looks like the blasted land between the trenches of Nullius Terram. It’s home to a number of warring cities, but they aren’t static settlements. Rather, some are floating fortresses that dwarf the Argonth of Breland, and others walk on two legs. The warforged colossus in Eberron: Rising from the Last War could be used as a model for a small fortress.