(~5,000 Years Ago)
The Kaarn arrived in Nod in a migration that lasted decades. They came from a Domain whose name is lost, driven by some catastrophe they have never adequately described. The oldest Kaarn who still live in the city will say only that the place they came from stopped being liveable, and that the roads out of Nod were the only route that did not lead back to what they were fleeing.
The Kaarn Crossing transformed Nod's physical character. A species defined by constant biological growth needs space, and the Kaarn carved it out of the existing city with their hands and their mass. Entire neighborhoods were demolished and rebuilt to accommodate beings whose size could double over the course of a decade. The construction techniques they brought with them, designed for structures that needed to expand alongside their occupants, are still visible in the city's older districts, where doorframes are wide enough to drive a cart through and ceiling heights vary between floors for no apparent structural reason.
The Crossing also established the precedent that Nod would accept refugees from dying Domains. This precedent has been invoked by every species that arrived afterward.