There are different types of modifiers and Diablo 2 absorb is considered a Special Modifier.
Calculating absorb depends on what type of absorb you have (“absolute” or “percentage”), and the order of operations.
Diablo 2 Absorb Type
- Absolute: An absolute or integer absorb is a fixed number of absorbed damage. For example, the Thundergod’s Vigor unique belt has +20 lightning absorb. There is no cap on absolute absorb.
- Percentage: An example is the Raven Frost unique ring, which has 20% cold absorb. Percentage absorb is capped at 40% per element.
Order of Operations
To calculate the actual damage taken, use this sequence.
Take the attack damage, then modify it by:
- Calculate resistance
- Calculate % absorb
- Calculate absolute absorb
- Add healing from absolute absorb (will not exceed your character’s max hit points)*
- Calculate remaining attack damage.
* Note: Note that the healing from absolute absorb only functions if your character can be healed by that much. If at full health, they will not receive healing. If you are 20 hit points down and get 50 healing from absolute absorb, only 20 will have any effect.
10,000 damage attack to a character with 95% resistance to that element, 40% absorb to that element, and 55 absolute absorb to that element.
- 500 damage after resist.
- 100 damage after % absorb.
- With 55 absolute absorb, 100 damage becomes +10 life. (100 – 55. 55 added to health. -45 remaining damage = +10)
High resistances and absorb (of both types) can turn devastating attacks into negligible damage, or even give you healing from them.
The resistance is the most important aspect, and that very high resistance is essential to make absorb a healing bonus.
If the character in Example 1 above had the same absorb, but 75% resistance instead of 95%, the damage equation would change: 2500 after resistance, => 500 after absorb % => +55 hit points, -445 damage = 390 damage taken.
- With 50% resistance it would be 890 damage.
- With 0% resistance you would be dead. (5890 damage.)
Absorb types and uses
Lightning absorb is the most useful as lightning damage often comes in multiple smaller bursts, such as from Lightning Enchanted bosses or the multiple hits from a lighting bolt. Absorb is less useful against fire and cold, since they more often one big blast. Poison absorb is not found in Diablo 2.
“Magic Absorb” such as that found on the ‘Spirit’ Rune Word works only against magic damage and has no effect on elemental damage.
Physical Damage Absorb
Physical damage can not be absorbed, only resisted. There are two forms of physical resistance:
Percentage physical damage reduction
- Granted by the modifier “Damage reduced by x%”
- Commonly known as DR%
- Capped at 50%, but can be stacked to counter the effect of Decrepify and Amplify Damage which apply -50% and -100% physical resistance respectively.
- Applied after integer damage reduction
- Often found on items which are otherwise useful such as Stormshield Monarch or String of Ears Demonhide Sash.
Integer (absolute) physical damage reduction
- Granted by the modifier “Damage reduced by x”
- Commonly known as iPDR or iDR
- Applied before percentage damage reduction
- Since the best sources are often relatively rare magic items (there are exceptions like The Gladiator’s Bane Wire Fleece and Gerke’s Sanctuary Pavise) it is hard to stack iDR to an amount where it becomes useful. However, if you manage to stack upwards of 100 iDR you’ll find yourself immune to many physical attacks.