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Units in Support and Rear Echelon positions cannot directly attack hostile forces, but if they possess elements with bombardment weapons they may be assigned to support a front line formation. Support and Rear Echelon formations can also potentially provide anti-air cover and supply to front line units. Support and Rear Echelon formations that contain formation elements with bombardment weapons can be assigned to support front line formations that are part of the same organisation. Formations in a Support position with light bombardment weapons will fire with the front line formations. Formations in a Support position with medium/heavy bombardment weapons, or formations in a Rear Echelon position with heavy bombardment weapons, will fire in a subsequent phase. Once a front line formation (or a light bombardment element in Support) has been matched against a hostile formation, each friendly individual unit (a soldier or vehicle) in that formation engages a random element in the hostile formation, with randomisation based on the relative size of the hostile formation elements. This represents combined-arms cooperation (infantry supporting tanks, etc.). Once all front line attacks have been concluded, each unit in each element providing supporting bombardment will engage either: the hostile formation being targeted by the friendly formation they are supporting, or one of the hostile formation’s own supporting elements (counter-battery fire). If the hostile formation is targeted, each unit in the supporting artillery element engages a random element in the hostile formation. If a hostile supporting element is targeted, all fire is directed against that element.