COMBAT SYSTEM
These rules are changes to allow for a more realistic feel to combat in the AD&D game. They can be used in conjunction with the Armor System in another section, but work very well without them. The Defense Pool, Defensive Combat and Defense Rating rules may be a bit too much for some DMs and players, due to the many possible combinations the player can opt for, and the many numbers involved. For those who enjoy this added versatility, and can handle the math without annoyance, use them as they are explained below. For those who do not want to go through the hassle, perhaps these rules will at least give you some ideas.
This combat system uses a few terms I will define below: Base AC, Defense Pool, Defensive Combat, and Defensive Stance.
Base AC represents the AC the defender gets without actively defending himself, and is AC 20. This is the undefended AC, so flank/rear attacks get no added bonus to hit, they must hit this base AC only. If you do not use my Armor System, then armor would modify this base AC, as well as defenses that simulate armor, like bracers of defense. Otherwise, only plus oriented protective magic will modify this base AC, so rings/cloaks of protection, displacer cloaks, protection from evil spells, etc. all modify the base AC. Shields, pluses on them and shield like magic defenses, like the shield spell, do not modify base AC, but are a part of the Defensive Pool detailed later. The defender gets this base AC against all attacks, even back attacks. This base AC can be further modified by the Defense Pool below.
Defense Pool represents the defensive bonus a defender has due to his active defense and dodging or blocking. If the defender would not get this AC bonus if attacked from behind, you can bet it belongs to this Defense Pool. Dexterity bonuses, swashbuckler bonuses, monk defense bonuses, single weapon style bonuses, Defensive Combat bonuses(detailed later) and shield bonuses name most of the bonuses that belong here. Add up the total AC bonuses these various defenses would grant the defender normally, not including the Defensive Combat bonus, as it is best to keep it separate and just add its defensive bonuses separately, since it can change from round to round. This total is the Defense Pool of the defender. Each round it is renewed, and each round the defender can allot these points to defend against attackers. None of these points can be applied to flank or rear attacks, thus, these will always strike at the defender’s base AC. Each defense pool point must be applied to each attacker the defender faces, as a defense point only works against 1 attacker per round. Thus, if a defender is attacked by 3 orcs, all from the front, he must split his defense pool among them as he desires.
Base Defense Pool this represents the defense pool points all defenders will have from their natural/trained ability to defend themselves. Choose only 1 of the categories below to find the basic defensive ability of the defender.
Unarmed(Unskilled): these defenders have no weapon or item to use as a shield, and have no unarmed combat training either, they get only 2 defense pool points. These can but attempt to dodge around and hope for the best.
Unarmed(Skilled): these defenders are unarmed, but have martial arts skill. Those with 1 slot(proficiency) into such a style get 5 defense pool points, those specialized in a style get 10 defense pool points. These learn to deflect and dodge attacks with great skill.
Armed(Unskilled): those who have a weapon/item to deflect blows with, but are not proficient in the item itself, get 5 defense pool points. They can parry some blows, but not as well as those with skill. They do not use a shield.
Armed(Skilled): those with both a weapon and the skill to use it get 10 defense pool points. They can parry and keep enemies at bay with proficiency. They do not use a shield.
Shield Use(Unskilled): those who use a shield, but are not proficient in it, get a bonus depending on the shield. The bonus by shield type is Buckler/Small/Medium/Body gives 10/12/14/14. This is the defense pool bonus each shield gives when not used by a skilled defender. The body shield does not give more general protection than the medium shield, as its bulk and lack of mobility reduce any extra effectiveness from its increased size. However, because it is larger, it provides more cover and thus better defense against missile weapons, giving 20 defense points against all such attacks the shield can be positioned between.
Shield User(Skilled): those with proficiency in their shield, get an additional 2 point bonus over the unskilled defense pool above, except for the missile bonus of the Body Shield which remains 20 points.
So, for example, Thor is a warrior with an 18 DEX(4 defense pool points) and uses a medium shield in which he is skilled(16 points to the pool). Thus, all told, Thor has 20 points in his defense pool. Assuming he has no magic defenses or armor(if not using my armor rules), his base AC is 20. So, if he faces a single orc with 1 attack, he can put all his defense points against it, for an AC of 0(base of 20 - points from pool(20) = effective AC against that attack). If he faces 2 orcs, he would need to defend against each separately, and assuming even defense, he would put 10 points against each, so his AC would be 10 against each orc. Rear or flank attacks allow none of these points to be applied so they all strike the base AC 20.
Defensive Combat bonuses are those granted to skilled combatants. Basically, as a combatant learns to become more skilled in his weapon and combat, he learns an even mix of defensive and offensive fighting skills. Thus, fully half of his training is geared toward defense. This is where the defensive combat bonus comes from. Combatants can opt to use some of their combat skill toward defense rather than offense. The usual AD&D game assumes all is used in offense, but this system gives combatants a choice. To find the maximum defensive combat bonus a combatant can gain, first, find their base THAC0, only modified by any to hit bonus from weapon mastery. Strength, magic or any other bonuses to hit are not counted for this. Find this THAC0, and subtract it from 21. This gives the improvement in skill the combatant has earned. Half of this skill improvement can be used for defense. Just divide this number by 2, rounding all fractions down. This gives the Defensive Combat Bonus the combatant can use. Note this value on the sheet near the weapon THAC0, and then add it to the fully modified normal weapon THAC0 of the combatant. Yes, this makes the combatant’s THAC0 worse, and this modified THAC0 becomes his new THAC0. The combatant must decide how much of this Defensive Combat Bonus to apply to attack(THAC0) and how much to defense(defense pool). Whatever is applied to attack, reduces his THAC0 by that much for that round and what is left over(if any) is added to his Defense Pool. These left over points, which are added to the defense pool, act just as Defense Pool points, and cannot be applied to flank or rear attacks.
For example, Thor is a 7th level warrior specialist in sword. His STR is 18/00, and his sword is +3. His normal THAC0 is 7. To find his DCB(defensive combat bonus) we find his THAC0 only modified by the +1 from specialization. This is 13. We take this and subtract it from 21, so 21-13 is 8. Divide this by 2 and we get a DCB of 4. We take this and add it to his original THAC0, and we see that Thor now has a THAC0 of 11 with a 4 DCB. Assume he is attacked by 1 orc. He can put all 4 points to defense so his AC against the orc would then be 4 better, and Thor would attack with an 11 THAC0 for the round. Now suppose 2 orcs attack. To defend, Thor decides to use all 4 points for defense, which he spreads evenly among the 2 attacking orcs, so 2 points to each, for a 2 point better AC against each. His THAC0 would be 11 since he chose to use all 4 DCB points for defense.
Defensive Stance this allows the defender to give up attacks or defensive actions to help when overwhelmed by numbers. Each attack given up increases the defense pool of the defender by 50% of its base value. This allows the defender to "turtle up" and defend himself better. However, a defender cannot apply more than his Defense Limit to any single attacker, this represents the best a defender can defend himself against a single foe, and this limit is simply the normal value of his defense pool, with combat defense added.
Rear Attacks are special not only in that, as for flank attacks, no defense pool can be applied against them, but also in that at the end of any round a foe threatens your back, regardless of how it happened, that foe gets an immediate attack of opportunity(a free attack). This only occurs at the end of the round(very slow phase), so if warrior can get his back covered before the round ends, he can probably avoid having a foe get this free attack on his back. Just remember, foes can move freely when not threatened, so if a warrior simply pivots to turn his back away from an attacker behind him, yet no one threatens the attacker to keep him pinned down, the attacker can simple move over(have such attackers save their half move until the end of the round) and get that free back attack. Being surrounded really sucks!
For example, Thor is now surrounded by 6 pissed off orcs. He has 2 attacks per round, and a free shield parry each round as well, because he is specialized in shield/weapon style. Poor Thor has 6 attackers to defend against. He can use his defense pool against up to 3 of them, since they are in his front hexes, while the other 3 are in his flank/rear hexes. The 3 back orcs attack AC 20, an easy hit! The 3 in front face Thor’s defenses, Base AC 20 with 20 defense pool points. He puts 6 against the front orc and 7 each to the side orcs, so the front orc faces AC 14, and the other 2 AC 13. Thor is in trouble! In addition, if an orc can maneuver so as to be behind Thor at the end of the round, he gets a free attack! However, Thor gets a free parry, but say he uses it in a defensive stance. His pool now becomes 30, 50% more than the 20 it was. Now each of the 3 front orcs hits AC 10. Thor has 4 DCB points also, so he could throw them in, for 24 points in his pool, plus 50% for defensive stance, or 36 points total. Now each of the 3 front orcs faces AC 8. If Thor really wanted, he has 2 attacks, so gives up 1, which adds another 50% to his pool, for a total of 48 points. Now each of the 3 orcs hits AC 4, much better, at least for the front! Now if Thor can get his back to a wall or a friend, he just might survive!
Body Shields/Medium Shields these 2 shields can allow the user to apply his defense pool bonus against the shield flank attacker. This is the only exception to the rule that defense cannot be applied to flank or rear attacks. However, only half of the defense pool points applied to this flank actually count, so this is not a very efficient defense, but better than nothing. A body shield always allows this, while a medium shield will also, but only if the user is both proficient in it and in shield/weapon style. These shields also allow parries/blocks to be applied to the shield flank, but give a 4 point result modifier to the attacker(this allows the attacker, if he hits, to modify his die roll by 4 points, so as to make parrying harder).
Shield Walls this can only be affected with medium or body shields. Those making the wall are limited to 1/2 their move rate, but gain several advantages. Against melee, they gain an additional 1 point into defense and most importantly, do not need to split up their defenses even if attacked by 2 attackers. This is the greatest advantage of the wall, it is so tightly packed that a defender need only worry about 1 attacker at a time, but this tightly packed wall also imposes a -2 to hit on all weapons except thrusting ones. Against missiles, body shield walls provide almost total coverage, all frontal missiles strike the shields, so only if a missile can pierce the shield will harm be done. Medium shield walls give 90% cover, so all frontal missiles must strike AC 0. To maintain a shield wall, a defender must have at least another shielded defender to each side. Those at the edges do not get the advantages, but must keep the slow move rate or ruin the advantage for the others near them. Also, only those with both shield/weapon style and shield proficiency can make such a wall work as stated. If some miss 1 of these skills, the wall is reduced to a move rate of 1/3 normal, a defender must have at least 1 of these skills to be part of a shield wall.