Shield Wall

If creatures stay along an even line in close order, they can form a shield wall by overlapping their shields. The shields must be medium or kite shields. Fighting with a shield wall has several benefits.

Versus Missiles

All members of the shield wall and any allies behind it are considered to be behind 50% cover (-4 AC bonus) versus missile fire. Shield walls block lines of fire indoors or underground, so in dungeon settings any allies behind the wall can't be targeted by hostile missile fire. The creatures actually forming the shield wall can still be struck, however.

Versus Melee

Since the members of the wall are in close order, shield walls allow them to concentrate their fighting power. They are also good for controlling enemy movement, especially in narrow areas such as dungeon corridors. Because the shields overlap, all members of the wall gain a -1 bonus to their Armor Class.

Creatures forming a shield wall must be of the same size or the wall won't work. In addition, they have to move together if they want to stay linked. A shield wall can only take a half-move without breaking apart.

Creatures in a shield wall are slightly limited in their choice of armament. They can fight only with one-handed weapons since they're using a shield in the other hand. If they use a slashing or bludgeoning (Type S or B) weapon, they suffer a -2 penalty to attack rolls unless the weapon is a smaller size category than they are, because the close order interferes with the weapon's swing. Piercing (Type P) weapons aren't affected by close order.

As an example, a human barbarian (size M) forms a shield wall with his companions. He can use his short sword (Type S, size S) or spear (Type P, size M) without penalty, but if he fights with his battle axe (Type S, size M) he suffers a -2 penalty to his attack rolls because he's so close to his allies.

Another excellent tactic for shield walls is to place long-range polearm wielders immediately behind the shield wall. Since the polearms can reach over the shield line, enemies can be exposed to several attacks at once when they close to melee range. Using a polearm over a friend creates a -2 penalty to attack rolls, however.