Age of Sigmar Fantasy Battles are extremely lucky. Marvellous, wonderful, amazing and great Creative Assembly gives out it’s map constructor Terry for Total War: Warhammer.
Right now it’s available as a beta-version for Windows 10 users, but release is planned for this month.
Wipe your tears and pick up your chins. Maps will be available only for single- and mutiplayer battles. No way to create an Ultuan Campaign here. The thing is that the developers use many different editing programms in their work. There is no unified programm for everything and CA is not planning to give out the rest.
Here is a forum on which developers eplain on how to work with this editor.