Spell Immunity status prevents the targeting of most spells (no matter what damage type they are) and grants a 100% Magic Resistance bonus. Whether or not a spell pierces immunity is unique to the spell.
Physical damage is caused by all standard attacks from units and some spells. All types of physical damage are resisted by Armor. Damage Block reduces damage from standard attacks. Cleave is unaffected by armor value but is still affected by armor type and damage block. Physical damage does not affect Ethereal units. Evasion grants the chance to dodge standard attacks, but will not dodge physical damage caused by a spell.
Physical damage caused by standard attacks can have different attack types depending on the type of unit, and they are affected by different armor types as listed in the table below.
|Attack Type||Armor Type|
|Basic Armor||Fortified Armor||Hero Armor|
- For a comprehensive list, see the Table of Armor and Damage Types
Hero attacks are used by all heroes, and a few special summons. It deals half damage to buildings and siege creeps.
The following mechanics remove hit points but do not trigger on-hit effects. The underlying mechanic is the damage source not causing a hit. This results in it being ignored by effects which only trigger on hit. A hit is defined as damage greater than 0 from a standard damage type (either physical, magical, or pure). Because the following mechanics do not cause a hit, they are considered Non-Damage Types and are in an entirely different category from standard Damage Types.
HP Cost does not count as damage and is always non-lethal. It cannot be reduced or amplified by anything.
|Armlet of Mordiggian||Unholy Strength|
Negative Regeneration does not count as damage but is always lethal. It cannot be reduced or amplified by anything.
Under certain conditions, some abilities may provide an instant kill. This has no damage type and simply kills the target when the requirements are met. This means that under shared damage effects, instant kill damage is not spread.
|Ancient Apparition||Ice Blast||Unit is under the threshold|
|Axe||Culling Blade||Unit is under the threshold|
|Brewmaster||Primal Split||If all the warriors die, Brewmaster dies|
|Clinkz||Death Pact||Unit is a non-ancient creep or summon|
|Disruptor||Glimpse||Unit is an illusion|
|Doom||Devour||Unit is a non-ancient creep or summon|
|Enigma||Demonic Conversion||Unit is a non-ancient creep or summon|
|Juggernaut||Omnislash||Unit is a non-ancient creep|
|Lich||Sacrifice||Unit is an allied lane creep|
|Lifestealer||Consume||Unit is non-hero and Infestable|
|Lion||Hex||Unit is an illusion|
|Mana Drain||Unit is an illusion|
|Lone Druid||Spirit Bear||If Lone Druid dies, the Spirit Bear also dies|
|Mirana||Sacred Arrow||Unit is a non-ancient creep or summon|
|Medusa||Stone Gaze||Unit is an illusion|
|Meepo||Divided We Stand||If one Meepo dies, they all die|
|Oracle||False Promise||Unit took too much damage|
|Phoenix||Supernova||If the sun dies, Phoenix also dies|
|Pugna||Life Drain||Unit is an illusion|
|Shadow Shaman||Hex||Unit is an illusion|
|Wraith King||Reincarnation||Wraith duration ends|
|Bloodstone||Pocket Deny||Instantly denies the user when used|
|Hand of Midas||Transmute||Unit is transmutable|
|Scythe of Vyse||Hex||Unit is an illusion|
|Vhoul Assassin||Envenomed Weapon|
Damage dealt by the following abilities cannot be reflected.
|Nyx Assassin||Spiked Carapace|
|Vhoul Assassin||Envenomed Weapon|
|Blade Mail||Damage Return|
|Patch Version||Balance Changes|