Armor

This article describes the mechanics describing hard objects and how difficult it is to harm them, including people wearing hard objects (armor). For these purposes, 'armor' describes the durability of objects, including armor.

All armor has two major components that describe how much it prevents damage. These are:


 * Deflection.
 * Absorption.

These properties are applied in order. Deflection takes effect first, followed by absorption. If the attacker's weapon has a penetration value, that affects both the target's deflection and absorption.

Deflection
Deflection is the armor's ability to redirect all of an attack's energy along a new vector. In other words, the attack bounces off harmlessly without leaving more than a scratch or dent. Deflection characterizes 'hard' armors, especially metal and ceramic. A tank's armor or a knight's suit of plate has high deflection.

When you hit a target with armor, compare the total damage you deal to the target's deflection.
 * If the damage is less than the armor's deflection value, the attack is completely ineffective. The target takes no damage.
 * If the damage is equal to or greater than the deflection, you might damage the target. Continue to absorption.

''Example: You attack a lightly armored vehicle with armor 10 deflection / 3 absorption. If you make an attack that deals 8 damage, even if it hits you still fail to deal damage since it was less than the deflection value (10). If you make an attack that deals 10 or more damage, continue to the next step (absorption).''

Absorption
Absorption describes the armor's ability to disperse an attack's energy quickly and evenly. The armor slows the striking point of the weapon; the attacker gets in a solid blow but it deals less damage. High absorption defines 'soft' armors, such as cloth, leather, and woven composites. A flak jacket or a bullet-resistant vest has high absorption.

When you continue past a target's deflection, compare the damage to the target's absorption. Subtract the absorption value from the damage you dealt.

''Continuing the example, you hit the vehicle (10 def / 3 abs) with an attack that deals 10 damage. That 10 damage is reduced to 7 (10 damage - 3 absorption).''

It is possible for an attack that ignores deflection to still deal no damage, if the target's absorption is high enough. This is likely to happen with a relatively low-damage attack hitting a target wearing soft armor like a bullet-resistant vest. An attack can't deal less than 0 damage.

Penetration
It is possible to punch through armor using weapons with penetration. A few melee weapons have penetration, but it's much more common for firearms. Using the right weapon or ammunition type, you can threaten targets like tanks and Goliath suits that are normally immune to small arms fire.

When you successfully hit an armored target with an attack, penetration works like bonus damage but only for the purposes of overcoming the target's deflection and absorption. Furthermore, this bonus penetration damage splits, or depletes -- first exactly enough to overcome deflection (if necessary), and then the rest to mitigate absorption. Any bonus penetration damage left over does not apply to the target as actual damage; it counts against deflection and absorption only.

Again, it is possible even with penetration to still deal no actual damage to the target, if its armor is strong enough.

''Example: You attack an APC that has armor with 20 deflection / 10 absorption. You're using a .50 BMG antimateriel rifle with a penetration of 8.
 * You hit the target for 25 damage. This is enough to overcome the 20 deflection, so the attack ignores deflection and goes to absorption.  Normally the 10 absorption would reduce your damage to 15 (25 damage - 10 absorption).  However, your weapon's 8 penetration counts as bonus damage but only for overcoming the absorption.  All 8 of that damage goes to the absorption, leaving 2 absorption to affect the actual damage.  The total damage you deal is 23.
 * You load your rifle with ammunition with improved armor-piercing qualities, bumping its total penetration up to 13. You again hit the target for 25 damage.  This time, your improved penetration mitigates all of the armor's absorption.  You deal a full 25 damage to the target.  (Although you had more penetration than the target had absorption, the bonus penetration damage applied only for mitigating absorption.)

Now you face a light tank with armor 30 deflection / 15 absorption. Again your weapon has a penetration of 8.
 * You hit the target for 25 damage. Normally this would not be enough to overcome the target's deflection, and your shot would bounce off harmlessly.  However, you can apply the 8 bonus penetration damage to overcome deflection.  You use 5 of the bonus damage to do so, boosting your damage compared to deflection to 30 -- exactly enough to overcome it.  Moving on to absorption, your attack would normally do 10 damage (25 original damage - 15 absorption).  However, you still have 3 bonus penetration damage to apply to the absorption, reducing its effectiveness to 12.  You deal 13 damage (25 original damage - 13 absorption).''

Question: "Why is penetration so complicated?" Answer: This system ensures that penetration is useful against both deflection and absorption without being too powerful against either. Since an armored target's deflection and absorption can be radically different (up to a factor of 10), having penetration reduce both by the same amount might, in certain cases, might make penetration either too powerful or too useless. Furthermore, this way of applying penetration is relatively realistic -- it's generally more effective against soft armors but still useful against hard armor.