Armor as Damage Reduction

In this system, armor offers two benefits against attacks: an armor bonus to AC, which functions just like the armor bonus in the standard D&D rules but is usually lower in value; and damage reduction. See the table below for the armor bonus and DR values for common armor types. All other armor statistics, such as maximum Dexterity bonus, armor check penalty, and arcane spell failure chance are unchanged.

All enhancement bonuses improve only the Armor bonus of the armor, thus a suit of Full Plate +3 has an AC bonus of +7 and a DR of 4/-. Damage reduction provided by armor is applied first and stacks with any other form of damage reduction.

Shields

Shields function normally in this variant, providing their full shield bonus to AC. Unlike armor, a shield's effectiveness is measured wholly by its ability to keep an attack from connecting with your body.

Natural Armor

A creature's natural armor also provides a modicum of damage reduction. Divide the monster's natural armor bonus (not including enhancement bonus) by 5 to determine the monster's damage reduction. The same value is subtracted from the monster's natural armor class bonus to AC to find the monster's new AC.

ArmorACDR
Padded+1none
Leather+11/-
Studded Leather+21/-
Chain Shirt+22/-
Hide+21/-
Scale mail+22/-
Chainmail+32/-
Breastplate+32/-
Splint mail+33/-
Banded mail+33/-
Half-plate+43/-
Full plate+44/-