As the four armies clash on the surface of the planet, the (NPC) High Command for each army receives intelligence and set objectives to act on. Campaign objectives are always opposed by at least one other faction. These grand clashes rage across one or more of the continents on the surface for a set period of time.
When the High Command receives new intelligence, they change their objectives and focus their efforts into a new campaign on a different continent (or continents). The results of the previous campaign will be meaningful and some campaigns will be story driven, helping to uncover more about the lore of the universe and the planet itself.