I've noticed that if a unit has <Domain>DOMAIN_AIR</Domain> in their Row, they will automatically be treated as an air unit, restricted from existing anywhere but a city and has the Rebase mission with no attack capability. What I don't see is where that is all decided. In CIV5Domains.xml, it only defines the domain description and nothing else. Where are domains coded to behave a certain way? I don't see it in LUA either. Anybody have any idea?