What i did was use auto resolve

There are the Nightsister Hunters (Bow sisters), the wraiths (green ghosts), the undead Nightsisters, and the Nightsister warriors (sword sisters). The hunters and the Wraiths are the victory-relevant units you need to kill. The warrior huts are destroyable, but the undead spawners are not destroyable. The Nightsisters don't have a structure that you'll need to destroy it's just the units.