Damage Manipulation



Damage manipulation is a mechanic that alters damage values, either increasing or reducing it. Damage can be manipulated on both ends, from the dealing unit (outgoing damage) and the receiving unit (incoming damage). Armor and magic resistance are the most common damage manipulators, affecting incoming physical and magical damage respectively. Besides armor and magic resistance, a general damage manipulator exists, which is used by almost all other sources of damage manipulation. This manipulator is more flexible, and can amplify or reduce any kind of damage and may affect attack damage, spell damage, or both at the same time.

Generic Damage Manipulator
The generic damage manipulator is divided into incoming and outgoing damage manipulation, which results in them stacking multiplicatively. Most abilities that affect damage use the generic damage manipulator.

Incoming Damage
Incoming damage manipulation causes the afflicted unit to take increased or reduced damage. All sources within these lists stack additively with each other.

Armor and magic resistance work with incoming damage as well, but are handled separately and not by the generic damage manipulator. This results in them stacking multiplicatively with the general damage manipulator.

Outgoing Damage
Outgoing damage manipulation causes the afflicted unit to deal increased or reduced damage. All sources within these lists stack additively with each other.

There currently are no abilities that reduce outgoing damage using the generic damage manipulator.

Spell damage amplification is handled by the general damage manipulator, and not separately. This means all sources of outgoing damage manipulation stack additively with spell damage amplification as well.

Talents
The following heroes have a talent that grants them damage amplification that only affects spell damage.

Besides these, the following heroes have other specific spell damage amplification talents.

Items
The following items grant their wielder damage amplification that only affects spell damage.

Unique Damage Manipulators
There are several damage manipulating abilities that do not use the generic damage manipulator. This results in them all stacking multiplicatively with each other and with abilities that do use the generic damage manipulator.

For these abilities, this means if their value is 100%, they are absolute and cannot be altered in any way.

Stacking damage reduction & amplification
Armor and magic resistance work separately from other damage manipulators. This means they always stack multiplicatively with any other listed ability.

Besides 's rum and, all damage reducing and damage amplifying effects stack additively with each other. Ghostship and Mana Shield stack multiplicatively with them. Mana Shield also stacks multiplicatively with Ghostship. The damage amplification which illusions usually have stacks multiplicatively with all other damage amplifying and reducing effects (considering they are able to affect illusions).

Examples of additive stacking (all values consider highest possible value, examples ignore armor and magic resistance, 100% is the base value):


 * Ursa affected by and max level  takes:


 * Spectre affected by and   takes:


 * A hero affected by and max level  takes:

Examples of multiplicative stacking:


 * Medusa affected by and max level  takes:


 * Medusa affected by the same as above, but also additionally by takes:


 * A illusion (taking   damage) affected by max level  and   takes:

Stacking outgoing damage manipulation stacks in the same way as incoming damage manipulation, i.e. additively. However, since incoming and outgoing manipulations happen at different times (outgoing happens first), they stack multiplicatively with each other.

Damage negation
Damage negation causes entire instances of damage to deal no damage to its target, however, the instance is still registered. This means, if something reacts on damage without having a minimum damage threshold, it still reacts on the negated damage.

It is unknown whether these abilities use a separate mechanic to completely negate damage, or if they use the same unique damage manipulators as and  do, but with their values set to 100%.

Preventing on-damage effects
Many abilities react on damage a unit receives. In some cases, fully negating the damage causes them to not proc. However, some on-damage effects also react on 0 damage so they still may proc even when the proccing damage got negated.

The following abilities and effects do not react on damage when it gets fully negated (reduced to 0):

1 These work when the damage gets negated by.

2 These abilities have damage counters, which do not work when the damage gets negated.

3 Includes all sources of lifesteal and spell lifesteal, except, and 's Spell Lifesteal, which are listed separately.

The following abilities still do react on fully negated damage:

1 The damage of and the damage spread of  are fully unaffected by any form of reduction, except for magic resistance and armor.

Min Health
Min Health, just like regular damage negation, prevents a unit from dying. However, the way in which that is achieved is completely different. Instead of directly reducing or negating damage, this mechanic rather manipulates the health of the unit. This property (MODIFIER_PROPERTY_MIN_HEALTH) prevents a unit's health from dropping below the value it is set to. It does not affect the damage itself, meaning on-damage effects react on the full damage, and not how much damage was dealt effectively, so they can be triggered normally.

The following abilities use the Min Health mechanic:

Манипуляция уроном 伤害调整