Heroes can move around the adventure map to capture mines, reach friendly or hostile towns, pick up loose resources or artifacts, and other things. By default, any part of the adventure map that the player hasn't visited is hidden from view under a black fog. In Heroes IV, any part of the adventure map that the hero can't currently see is under a gray fog of war - they can still see the surrounding land, but any hostile or neutral forces are hidden from view until they move close enough to be spotted.