In Darkfall, players and clans are allowed to build cities and hamlets and war with them. I have been a Darkfall player for a while, but I have not done that. Because of that, I do not know much of it in details. As far as I know, you need a clan together with a city to be warred against, and need to put up your own city. For the quality or other material, for example whether it should be vulnerable, no guard tower, I have no clear idea. You also need gold to wage war on another clan. According to what I know, it seems there is certain clan KoS system, as I have been told I have been on some clan’s list.