Damage types

Damage is any means by which unit's current health can be reduced. Heroes, creeps, towers and fountains are all capable of dealing damage.

Damage sources
Damage can be dealt by attacks, abilities and items. Attack damage is the damage dealt per attack, and is displayed on the sword icon in the HUD. Heroes start off with a basic damage plus 1 extra damage per point of primary attribute. As heroes level up, they gain primary attributes and therefore gain damage. Items that grant increased "Damage" increase attack damage, and do not affect abilities and items. Abilities and items can also deal damage. These are generally fixed. However, some abilities can be upgraded with, while others scale with hero stats, conditions or enemy health etc.

Attack damage
Attack damage is dealt by regular physical attacks. It is influenced by a couple of factors such as the value of the attack damage itself, the according attack damage types, armor and the armor types, damage block and others.

Spell damage
Spell damage is all damage which is not dealt by physical attacks. This includes all spells which deal magical, physical or pure damage. Even the damage dealt by attack modifiers counts as spell damage, as long as the effect deals its damage in a separate instance from the attack damage.

Spells can be amplified with, , , and. The damage amplification sources stack all additively. The amplification does not only affect spell damage dealt against enemies, it also causes damage afflicted to allies or the own unit to get amplified.

Another effect making exclusive use of spell damage is 's Spell Lifesteal.

Damage classification
All forms of damage in Dota 2 are classified by damage types. There are 3 primary damage types: Physical, Magical, and Pure. Physical Damage can be reduced by Physical Armor or Damage Block, Magical Damage can be reduced by Magical Damage Resistance, while Pure Damage cannot be reduced by either armor or magical damage resistance. All 3 primary damage types have some interaction with other damage-related game mechanics as noted in the table below. Damage may also have the HP Removal flag, causing the damage to ignore some mechanics which would manipulate it otherwise.

1 The only exceptions are and, whose damage is blocked.

2 These categories only count ability effects which directly manipulate damage, reducing, amplifying or completely blocking them, such as, and. They do not include abilities which amplify or reduce damage by increasing/reducing magic resistance/armor of units, such as, , and.

3 By itself, spell immunity does not interact with any damage type. All spells are rated as to whether or not they can pierce spell immunity independent of their damage type. Thus, spell immunity only governs if a spell has any effect, not how much damage it inflicts. To receive no effects from a spell, the spell must not pierce spell immunity and the target would require both spell immunity and 100% damage reduction of the damage type the spell inflicts. A 0 damage instance is still registered and may proc on-damage effects (unless it is flagged as HP Removal). If a spell does not pierce spell immunity, then it does not attempt to damage the target in the first place, so that no 0 damage instance occurs.

Physical attack damage
Physical damage can be inflicted by regular attacks from all units (including structures), and by certain abilities. Physical damage is modified by both armor and Damage Block, is unaffected by magic resistance, and cannot affect ethereal units. The abilities and  make their targets completely immune to physical damage, although they can still be targeted by attacks and abilities.

Physical spell damage
Physical damage from abilities (and theoretically items) is usually unaffected by armor type. The exceptions are Exorcism and physical damage abilities that add their damage directly to the hero's attack, which have the hero attack damage type, dealing 50% to structure armor type (used by all buildings and siege creeps), and 100% to all other types. They are all affected by armor value, but none by evasion and Damage Block (except for and, which are affected by Damage Block).

The following hero abilities deal physical damage (summoning abilities and simple attack damage buffs are not listed):

1 Damage is directly added to the unit's attack damage.

2 Damage from these abilities is affected by armor type as well.

3 Half of damage dealt is physical, the other half magical.

4 Damage is blocked by Damage Block.

Magical
Magical Damage is caused primarily by spells, although not all do magic damage. Magic damage is reduced by magic resistance, and deals higher damage against ethereal units. The majority of abilities in Dota 2 deal magical damage.

All abilities not explicitly listed under another damage type section inflict magical damage.

Pure
Pure Damage is a damage type that is not reduced by magic resistance nor amplified by magical damage amplification like. It also fully ignores armor and Damage Block. However, it can be reduced or amplified by skills which reduce/amplify every damage type, like. Pure damage affects spell immune units (since spell immunity does not block damage by itself), but that does not mean that a spell with pure damage can target spell immune units (e.g. deals pure damage, but cannot be cast on spell immune units). It does not affect invulnerable units.

The following abilities deal pure damage:

1 Mist Coil deals pure damage to the caster, but magical damage to the target.

2 Burning Spear and Macropyre deal pure damage only when taking their respective level 25 talent, else they deal magical damage.

3 Laguna Blade deals pure damage only when upgraded by, else it deals magical damage.

Flags
Several abilities have certain flags that cause them to behave differently in certain situations. There are 2 different flags: The HP Removal flag and the No-reflection flag. All spells can be flagged, regardless of what damage type they use.

HP Removal flag
Spells flagged as HP Removal fully ignore any form of damage manipulation (with a few exceptions listed below), means they cannot be amplified, reduced or blocked except by magic resistance and magical damage barriers in case of magical damage and armor in case of physical damage, which is also reduced by damage block. They also ignore and do not trigger any on-damage effects, making them unable to cancel consumables for example. Most spells flagged as HP Removal deal pure damage. The HP Removal flag also causes damage to ignore invulnerability, however, this is not always the case. Even when flagged, the damage is still registered as such and may be counted by statistics as damage.

Note: Not all source of health loss are damage. Several abilities which reduce a unit's health without triggering on-damage effects do so by directly setting a unit's health to specific values. Unlike damage with the HP removal flag, these health manipulation truly bypass any on-damage effect and are not registered as damage at all. For more details, see Health setting.

The following abilities use the HP removal flag

1 These abilities delay damage. The delayed damage is pure and has the HP Removal flag.

2 deals magic damage flagged as HP removal to the caster.

3 deals magic damage flagged as HP removal to secondary units.

Besides all sources of damage manipulation and spell lifesteal, the following abilities and items do not react on damage which has the HP Removal flag:

No-reflection flag
The no-reflection flag causes several on-damage events not to interact with the damage of spells which have the no-reflection flag. This is to prevent infinite damage loops (for example 2 opposing heroes with ).

The following sources of damage have the no-reflection flag:

The following spells do not react on damage which has the no-reflection flag:

Instant kill
Besides damage, a unit may also be killed with the instant kill mechanic, without the actual use of damage. Similar to HP Removal, instant killing effects ignore almost everything and can only be prevented by a few spells.

Summoned units and illusions that expire after a set amount of time are killed with the instant kill mechanic. Summons and illusions that get replaced on cast are killed this way as well. The instant kill mechanic cannot bypass the min health mechanic by default. Instantly killing abilities which do bypass it do it with the help of special interactions coded into the abilities.

The following abilities use the instant kill mechanic

Damage manipulation
There are several ways to affect the final value of a damage instance. 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 (no similar trait exists for pure damage). They usually reduce damage, but can also amplify it if their values are negative. Spell damage amplification is the main trait for amplifying (but not for reducing) outgoing spell damage (no similar trait exists for attack damage). Besides these, there are some other ways to manipulate damage, ranging from amplifying damage, reducing damage and even negating damage completely.

Removed damage types
The following damage types were removed in patch 6.82 in order to simplify the game mechanics.

Composite
Composite damage (also known as mixed damage) was a damage type that was reduced by both armor and magic resistance. It pierced spell immunity and did not affect ethereal units. This damage type was used by, , , 's backlash damage, and. All of them were changed to physical damage, except for the backlash damage from the Spirit Bear, which was changed to pure damage.

Universal
Universal damage was a damage type that pierced spell immunity and was affected by magic resistance. This damage type was previously used by, , 's initial damage, , upgraded , , and. Doom, Midnight Pulse, Flaming Fists and Aghanim's Scepter upgraded Laguna Blade were changed to deal pure damage, allowing them to still pierce spell immunity, while Pulverize, Echo Slam's initial damage and March of the Machines were changed to deal magical damage, and thus no longer pierce spell immunity.

Version history
Tipos de dano Типы урона 伤害类型