Attacking (DMG)

Once characters decide to attack and the order of initiative has been determined, it is time to resolve all the action. Many factors must be considered in each attack: How many people can surround a character? Will a shield block an attack from the rear? Can a character run across a chamber, dodging attackers, in a single round? Can a character win without killing his foe? Is it possible to block an attack?
Although the mechanics of combat are very simple, there are many different and unusual situations that come up during role-playing battles. Every battle is unique. One key to DMing memorable combat scenes is to remember that not every situation can be anticipated; you just have to combine the rules here with good judgment.
==Number of Attackers==
There is a limit to how many attackers can surround a single target. Many factors come into play, notably the relative size of the opponent, the length of the weapons used, and physical obstructions in the area. The obstructions will vary from battlefield to battlefield.
==Facing==
Each character or creature is assumed to have a front, flanks, and rear. When creatures of equal size are battling, up to six can surround a single figure.
Normally, a defender attempts to keep his opponents in sight. Thus, if there are no special circumstances (such as a thief moving silently behind the defender), opponents first occupy the front, then the flanks, and finally the rear. It's assumed that the defender will try to keep attackers from getting around him.
The diagram and description apply only when combat involves creatures of the same size. If the attacker is one size greater than the defenders, he occupies two spaces on the diagram. For creatures two sizes or more larger (small creatures attacking a large one, for example), the attacker occupies four spaces.
Thus, a hill giant attacking Horace the fighter would fill two of the spaces, allowing only four orcs to join the attack. If there were two giants attacking, only two orcs could join the combat. When attacking a small creature, one giant and two orcs could make the attack. Any more than this and the attackers would just get in each other's way.
==Weapon Length==
The actual size of a weapon has little to do with the space needed to wield it. An awl pike is 12 to 20 feet long, yet since it is a thrusting weapon it needs virtually no space side-to-side. It does, however, need that 12 to 20 feet in front! A sabre and a battle-axe are about the same size, but the battle axe requires more space—the sabre can be thrust straight forward into a narrower space, while the battle axe must be swung mightily, which takes a lot of space.
The DM must decide whether a character has enough space to use a particular weapon in a particular setting and situation.
\As a guideline, the AD&D rules assume that two fighters using swords can work side-by-side in a 10-foot-wide area. The same space would be filled by one fighter using a two-handed sword.
==Position of Attackers and Attack Rolls==
Besides determining the number of attackers a single character can face, the relative positions of attackers affect the chance to hit.
Characters attacked from the rear do not gain their Dexterity-based Armor Class bonus, and their attacker gains a +2 bonus to his attack roll. There might also be penalties if the optional Shields and Weapon Frontage rule is used.
==Pole Arms and Weapon Frontage (Optional Rule)==
Pole arms and similar thrusting weapons are designed primarily for use in highly specialized formations. The average length of these weapons—12 to 20 feet—makes their use in individual combat silly, if not futile.
An opponent can easily slip inside the reach of the pole arm, at which point the poor pikeman can only try to back up or drop his weapon. Little else is likely to be effective. However, if the same man with a pike is lined up with 30 of his fellows in a nice tight formation, he suddenly becomes very dangerous. Where one pikeman presented only a lone spear point, 30 pikemen present a deadly thicket.
The pole arm's big advantage is the small frontage each man needs to be effective. A man using a piercing pole arm can use his weapon effectively with just three feet of space, side-to-side. This allows a tightly packed line of pikemen.
In a group, men armed with pole arms should be set for defense or advancing slowly ( normal movement rate). They automatically make their attack rolls prior to any opponent attempting to close with them. However, after the first round of combat any surviving opponents are inside the reach of the pole arms and the pikemen must drop their pikes and draw weapons more suitable for close-in work.
==Shields and Weapon Frontage (Optional Rule)==
A shield is an item of limited size, strapped to only one arm or slung on a character's back. Characters generally position a shield so it offers maximum protection. Usually, this means it protects the shield-arm side of the body, most frequently the left side of a right-handed character. In this position, attacks from the rear or rear flanks of the character can't be blocked by a shield. In these cases, the shield's AC bonus is not applied to the THAC0.
It is possible to strap a shield to one's back. If this is done, the shield bonus is applied to the rear of the character, but the character can't use the shield to protect his front. Furthermore, the straps hinder the character's movement, giving him a -2 penalty to his attack roll.