In King's Empire, you can engage in battle with NPC's as well as online players. When attacking online players make sure to have a much stronger army than the defense since they will also have the wall to aide them in the defense of their cities. When attacking Robber camps, Ashka Brotherhoods, and Scarlet Crusaders, it is a good idea to discard the magic defense your troops have since these NPC's have no magic units.