Damage reduction

Description
Absorption is an effect found on some Warrior-specific equipment that reduces damage. All sources of absorption are global; they will reduce damage no matter which part of the body is hit. There are three main sources of absorption: armor, runes, and shields. To get maximum damage reduction, you only need one Rune of Absorption and one piece of damage-reducing armor. Additional runes and damage-reducing armor will not reduce damage further.

Armor
Ascalon Armor and Knight's Armor reduce damage taken by 2. Absorption from Knight's/Ascalon armor affects most sources of damage, although a few skills like Giant Stomp are not reduced by armor absorption. Knight's/Ascalon armor has the lowest armor level of the Warrior armors, so they are normally worn as the boots or gloves since those locations are hit less often. However, as Warriors sometimes use Stonefist Gauntlets, the boots are the most effective location. Ascalon armor does not stack with Knight's armor. Use only one piece of one type.

Runes
Runes of Absorption reduce attack damage by 1-3 depending on potency. Minor Runes of Absorption reduce damage by 1, Major by 2, and Superior by 3. Runes of Absorption only reduce damage from attacks and have no effect on spells or other sources of damage. Like all runes, Runes of Absorption do not stack with each other, even though they do not have (non-stacking) in their description like the absorption armors or other types of runes.

Shields
Shields may have up to two reduction modifiers, each with different requirements. Damage from all sources are reduced, even those that armor absorption doesn't reduce. Two absorption modifiers on the same shield will stack so long as both requirements are met. Shield absorption is global and does not depend on which direction you are hit from.

Quests and Collectors
Some quests and collectors may provide items with absorption properties, such as Blankets for the Settlers, Ruins of Surmia, or Martel Bastions. These modifiers are similar to shield absorption modifiers and will reduce damage so long their requirements are met. However, this kind of damage absorption is not a property found on dropped items, so do not expect to find a dropped weapon with an absorption effect.

Absorption chart
A list of the most common sources of absorption: Note that the 1-10% chance shields are from before the March 02, 2006 update which increased the maximum from -3 (10% chance) to -5 (20% chance).