Current questions and answers regarding the map editor.

Hello. I understand that the questions might seem a bit strange, but here they are: Is it possible to create a completely new hero on one map and then make that hero available on multiple maps? Would I need to create a mod, or can I manually add the hero's path in the map-xdb file? Also, is it possible to make the campaign levels unlock in a non-sequential order? Or is it still possible to implement this? Thank you in advance.