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, as well as all items with abilities that deal 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.

Magic spell damage is influenced by magic resistance, physical spell damage is influenced by armor and pure damage is not affected by either. All three underlie damage manipulation.

Spell Damage Manipulation
Spell damage can be directly amplified or reduced. Spell damage manipulation is divided into outgoing and incoming damage manipulation.

Since these are handled separately, they stack multiplicatively with each other.

Outgoing Spell Damage Manipulation
A unit that has outgoing spell damage manipulation deals more or less spell damage with any spell damage they apply to any unit. Multiple sources of outgoing spell damage manipulation stack additively.

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

Outgoing spell damage amplification granting items
Many items grant their owners a spell damage amplification bonus by giving them a direct bonus. The effects are limited to the item's owner, which must have the item equipped.

Incoming spell damage amplification
A unit that has incoming spell damage amplification takes more spell damage from any spell damage they receive from any unit. Multiple sources of incoming spell damage amplification stack additively.

Unlike outgoing spell damage amplification, incoming spell damage amplification affects every source of spell damage, as long as it is not flagged as HP Removal.

Unaffected by manipulation
There are certain cases of abilities that ignore spell damage amplification. It is important to note that those spells cannot spell lifesteal either.

In general abilities related to health manipulation (instantly killing effect, health cost, delayed damage) are not affected by spell damage amplification, neither incoming nor outgoing.

Spell damage dealt by summons is affected by the summons' outgoing spell damage amplification, not by the summoner's (e.g. ).

On top of the aforementioned general restrictions, the following are not affected by outgoing spell damage amplification (note that they are affected by incoming spell damage amplification normally):

1 The damage of the bouncing attacks acquired via are unaffected by outgoing spell damage amplification. The Glaives' int-based damage is fully affected, including that of the bounces.

2 The damage of the bouncing attacks acquired via the talent are unaffected by outgoing spell damage amplification. The Overload's area damage is fully affected, including that of the bounces.

Patch History
Dano mágico Урон заклинаний 技能伤害