Damage block

Damage Block is a mechanic that reduces physical attack damage a unit takes by a flat amount. Most damage block abilities are chance-based and passive.

Mechanics
Damage block reduces any physical damage a unit takes from attacks or from cleave, with the exception of damage dealt by attacks from ward-type units. Damage block does not trigger against physical spell damage, with the exception of the abilities listed here. Unlike armor, damage block reduces a fixed amount of damage, instead of a percentage.

When damage block triggers, it blocks damage before other damage reducing effects do. This means that the higher the unit's armor is, the less effective damage block gets. See total attack damage for the complete calculation.

All chance-based sources of damage block use pseudo-random distribution.

Blocked Spell Damage
The following abilities' damage is blocked by Damage Block.

1Only returned/reflected physical damage is blocked. Magical and pure damage is not blocked.

Not Blocked Instant Attacks
The following abilities' instant attacks' damage is not blocked by Damage Block.

Visual Feedback
When a damage block occurs, a ocher-colored negative number pops up on the unit, with a shield icon on the right side of the  number. This number shows the exact amount of damage blocked.

Stacking
The proc chances of all sources of Damage Block work independently from each other.

When multiple sources of Damage Block proc on the same attack, only the one with the highest blocked damage value takes effect. This results in multiplicative stacking behaviour.

The probability of proccing any damage block when you have multiple damage block sources can be expressed as:

Block Chance = 1 - \prod_{i=1}^n (1-p_i) $$

With $$p_i$$ being the Proc Chance of the $$i^{th}$$ source of Damage Block.

Examples

 * Example 1
 * has two in his inventory. What is the probability that one of them will proc when he is attacked?


 * As has a Damage Block proc chance of, the probability of Damage Block proccing when he is attacked is:


 * Example 2
 * is affected by and he has one  in his inventory. What is the probability for each source of Damage Block to proc?


 * The Proc Chance and Damage Block for both sources are:
 * from Crimson Guard: chance,  damage blocked
 * : chance,  damage blocked on a ranged hero like


 * As procs on every hit, and it's blocked damage value is greater than that of, only 's block will ever take effect,
 * and will have no effect on damage blocked.

Abilities Using Damage Block Rules
The following abilities follow the same targeting rules as damage block, and react on everything damage block does. However, the damage blocking done by these abilities is not considered damage block.

Recent Changes
Bloqueio de dano Блокировка урона 伤害格挡