User blog comment:Trulyrandom/Are Fanon Septs NCF?/@comment-15341185-20130813111909/@comment-4608429-20130813133826

Firstly, there is no such thing as a non-fire cast Sept. Every Sept has a mixture of all five casts. Secondly, a Sept isn't a world, it's a semi-interdependent region of space within the Tau Empire, and can have any number of additionally colonised planets, Space stations ect. Finally the Tau aren't that difficult to work with as long as you read between the lines of their canon. You can start to see all sorts of politics that exist within Tau society, and can make it quite interesting.