Melee: The Charge 1.1

In this case, we have two Spanish units {B-1, B-2} attacking a Roman unit {A}. Note that the Spanish units are both within their normal charge distance of 6", so they are not required to roll a d6 as the Romans are not evading the attacks. The Romans could evade but are not. The Spanish can both go in and as they do they will wheel their 22 degrees left or right of their facing. Consequently, they will basically straighten their lines (see The Charge 1.2) to meet the Romans.

Notice how the Spanish unit {B-2} has covered its flank by having another unit {B-3} on its right flank.

The red arrows show the axis of advance for the Spanish units. Axis of advance can be viewed in two ways: first, it can be interpreted as a unit's facing in relation to its path of movement toward its objective. Objectives can be enemy units or terrain features like hills and woods. Second, axis of advance can be understood to be the movement in relation to a unit's facing. Think of it as an imaginary line running from flank to flank (red arrows on B-1's flanks). A unit exposes their axis of advance by leaving a flank exposed and unprotected with an with an enemy facing it. B-2 has protected its axis of advance as mentioned. These are important tactical mechanics in historical gaming.