Defense Bonus
All characters have an innate defensive abilities that increase as they grow in level. These defensive abilities are a combination of nimbleness, luck and reaction, but most importantly experience. The defense bonus is a competence bonus to AC that stacks with all other bonuses except Armor or Natural Armor bonuses (gained from wearing armor and/or shield, or from using a spell or magic item that provides an armor or natural armor bonus). The defense bonus is not effective against touch attacks and ranged touch attacks.
The only exception is that a Fighter of level 3 or higher is so well-trained in wearing armor that the Fighter’s armor and defense bonuses stack (that is one of the reason that the Fighter’s defense bonus is as low as a Wizard’s – they train to rely on armor).
The defense bonus advancement table is shown below
FIGHTER/ WIZ / SOR
Level Bonus
1-2 +2
3-5 +3
6-8 +4
9-11 +5
12-14 +6
15-17 +7
18-20 +8
ROGUE
Level Bonus
1 +4
2-3 +5
4-6 +6
7-9 +7
10-12 +8
13-14 +9
15-16 +10
17-18 +11
19-20 +12
OTHER CLASSES
Level Bonus
1 +3
2-4 +4
5-6 +5
7-9 +6
10-11 +7
12-14 +8
15-16 +9
17-20 +10
For multi-class characters you add the total defense bonus and subtract 2, but the total bonus cannot be higher than the bonus of equivalent level of the characters most favorable bonus class. For multi-classed fighters only their fighter defense bonus stacks with armor.
Armor
Armor, especially the medium and heavy varieties, have many disadvantages – armor check penalties, a cap on the Dex bonus and even movement reduction. However, besides providing an AC bonus, armor also has one advantage – damage absorption.
An armor’s damage absorption (DA) is equal to ½ the total AC armor bonus (for example for armor and shield) rounded down. Thus, leather armor has a DA of 1, meaning that it absorbs 1 point of damage from every hit, while a chain shirt has a DA of 2, absorbing 2 points of damage from each hit. If all damage is absorbed, the character takes no damage from the attack.
Magical armor counts the enhancement bonus of the armor in the total AC bonus used to calculate the DA. Thus a +2 chain shirt has a DA of 3. However any AC bonuses due to an armor’s quality do not affect the DA.
Bypassing Armor DA
Armor DA can be bypassed in one of two ways:
1) when a critical threat is rolled on an attack roll that hits, DA is bypassed regardless of whether a critical is scored or not; and
2) a character can declare an armor bypass attack which carries a circumstance to hit penalty equal to the DA. Thus, to bypass chain mail (with a DA 2) requires a –2 penalty to hit, while bypassing full plate armor and large shield requires a –5. (NOTE: Vermin such as insects and other diminutive and fine size creatures are automatically considered to attempt armor bypassing attacks)
Armor DA and Spells / Sneak Attacks
Armor DA works a bit differently with respect to spells and sneak attacks. DA with respect to spells and sneak attacks is halved, rounded down, but it is subtracted from each die of damage taken. Only spells which are targeted by the caster and require a roll to hit may be declared as armor bypassing attacks.
Spell Example: Val wearing a chain shirt (DA2) is hit by 4 Magic missiles. His DA is halved to 1, but 1 pt is subtracted from each missile so the total damage from the magic missile spell is reduced by 4.
Sneak Attack Example: Silver, a 7th level rogue sneak attacks Korgan (who wears full plate -- DA4). The sneak attack does 1d6 from rapier and 4d6 from the sneak attack or 5d6 total (plus bonuses). Korgan’s DA is halved to 2, but 2 pts are subtracted from each die of damage so the total damage from the sneak attack is reduced by 10. Silver would be wise to try and bypass the DA.
Damage to Armor
While armor provides the advantage of damage absorption, it also becomes damaged in the process and will lose effectiveness unless repaired. Each piece of armor has a certain damage point capacity depending on its AC bonus and quality. The basic rule is that armor of average quality has 10 damage points per point of AC bonus. See the following Chart:
Armor Quality Dam. Points
Capacity per +1 of AC
Poor 5
Average 10
Good 12
Superior 15
Excellent 20
Masterwork 25
Each time a suit of armor absorbs damage points equal to its Damage Point Capacity / +1 AC, it looses 1 point from its AC protection (and this may impact the armor’s DA) . However, its DEX limit, Armor check penalty and movement reduction remain the same. The armor must be repaired to regain its bonus. Armor with an AC bonus of 0 is considered destroyed.
NOTE on Shields: Shields are quite sturdy, and metal (but not wooden) shields have twice the damage points of armor, meaning that an average quality metal shield has 20 damage points. A character who uses a shield may always opt to apply any damage points absorbed from an attack completely to the shield and not to his armor.
NOTE on Magic armor: All magic armor is considered to me Masterwork. Also, the enhancement bonus of the armor is not used to calculate the damage capacity. Thus a +2 chain shirt has 100 damage point capacity, not 150. When the damage capacity is reached, the magical armor is destroyed and counts as non-magical.
Armor Training – Option for non-fighters
Barbarians, striders, pramm hunters, rangers, druids or clerics can train to wear armor as well as fighters, but this is difficult. First, the character must have the appropriate Armor Proficiency feat. Second, the character must take a feat called Armor Specialization (which the fighters effectively get for free at 3rd level) that enables their defense bonus to stack with armor. However, when wearing armor in which they are specialized, their base defense bonus is calculated as if they were a fighter of their level before stacking with armor. Thus, an 8th level ranger (base Defense Bonus of +6) who specializes in medium armor and wears a chain shirt with a buckler (AC+6) is treated as an 8th level fighter (DB of +4) for the purpose of his DB stacking with the armor AC bonus (so the ranger’s total AC bonus from armor and DB is +10.)
