Set piece battles are fought between formations of opposing troop units arrayed in orderly ranks called battle lines. Battle lines vary in length and in structure with the terrain upon which the battle is fought. A battle line may be from two to twelve troop units in length (that many troop units lines up abreast) and may be structurally divided into as many as five different sections - LEFT FLANK, LEFT LINE, CENTER, RIGHT LINE and RIGHT FLANK. Certain types of terrain may require a battle line wihtout flanks, or with a very wide center, etc. A diagram of the exact length and structure of the battle lines determined by a particular terrain is called a battle configuration. For a complete listing of all these, see the Battle Configuration chart.

Some quick notes about the structure of battle lines:

1. In the center of a battle line, fighting is hard and heavy. Heavier armor is a great asset. Heavy cavalry can be devastating during the charge, but it is at a disadvantage once the melee begins. Heavy infantry types are at their best here.
2. Conditions on the left line and right line are much less packed. Medium troop types with higher mobility do well here.
3. The flanks are the most mobile areas of a battle line. There, a lightly armored (and fast) troop unit may be equal to a more heavily armored unit. Cavalry and archer units do well on the flanks.