Camps in DBA are basically considered to be static fortifications (offering a +2 bonus in close combat to the defender) to shelter the army and its baggage, and seem to be modeled on the classic Roman march camp, wagon laagers and the like. Many (perhaps most) armies in the field did not take the time to establish fortified camps, because they were on the move, because of the characteristics of the terrain or lack of tools/materials, and/or because such camps were not suited to their highly mobile form of warfare. A typical camp for a mobile army might be nothing more than a baggage train or herd of animals. There may also be circumstances where you would want to fight a DBA battle using an army on the march (i.e. with baggage train). This variant rule is designed for those armies and/or purposes.
With this variant, a player may opt to substitute a baggage train element for a camp prior to deployment. A baggage train should be depicted as a collection of draft animals (e.g. horses, camels, donkeys, oxen, etc.) with carts or baggage, drovers, camp followers and guards appropriate to that DBA army or period. The baggage train should conform to the size limitations for DBA camps (or DBM baggage elements).
A baggage train has a tactical move of 200p, may not move off-road in bad going (except for a camel train moving through dunes or oasis), and may utilize second or subsequent movement if moving along a road and movement will not contact enemy.
A baggage train may not move within a base width distance of any enemy troop, and may not provide support (including an overlap or flank bonus) to friendly troop elements.
In addition to its guards and drovers (equivalent to camp followers), a baggage train may be "garrisoned" by an element of foot or mounted. The train garrison should be placed somewhere on the train element.
Train "followers" and garrison receive a +1 bonus when in close combat or being shot at.
A baggage train otherwise functions like a camp for purposes of distance shooting, combat results, and victory conditions.