Lifesteal

Lifesteal is a mechanic which heals a player by a portion of the damage they deal to an opponent. There are two main types of lifesteal, each with an associated stat: Bullet Lifesteal, which returns a portion of the bullet damage dealt, and Spirit Lifesteal, which returns a portion of the spirit damage dealt. Bullet and Spirit Lifesteal are calculated identically, but are affected by different items.

Formula

Despite being presented in-game as +X% Bullet/Spirit Lifesteal, different sources of lifesteal stack multiplicatively, not additively. With $n$ different sources of the same category of lifesteal, final lifesteal $L_F$ is given by:

$L_F=1-\prod _{i=1}^n(1-L_i)$

where $L_i$ is the lifesteal provided by the $i$th source. Bullet and Spirit Lifesteal are calculated independently of each other, but both use the same formula.

Example

With 10% Bullet Lifesteal from Crippling Headshot and 35% Bullet Lifesteal from Leech, the player's final bullet lifesteal is:

$L_F=1-(1-0.10)\times (1-0.35)=41.5\mathrm{\%}$

This means that any time the player deals bullet damage to any opponent (including denizens), they will immediately be healed by 41.5% of the damage dealt. Note that the in-game user interface is inconsistent in how it rounds the final lifesteal percentage.

Bullet Lifesteal

Lifesteal is a mechanic which heals a player by a portion of the damage they deal to an opponent. There are two main types of lifesteal, each with an associated stat: Bullet Lifesteal, which returns a portion of the bullet damage dealt, and Spirit Lifesteal, which returns a portion of the spirit damage dealt. Bullet and Spirit Lifesteal are calculated identically, but are affected by different items.

Formula

Despite being presented in-game as +X% Bullet/Spirit Lifesteal, different sources of lifesteal stack multiplicatively, not additively. With $n$ different sources of the same category of lifesteal, final lifesteal $L_F$ is given by:

$L_F=1-\prod _{i=1}^n(1-L_i)$

where $L_i$ is the lifesteal provided by the $i$th source. Bullet and Spirit Lifesteal are calculated independently of each other, but both use the same formula.

Example

With 10% Bullet Lifesteal from Crippling Headshot and 35% Bullet Lifesteal from Leech, the player's final bullet lifesteal is:

$L_F=1-(1-0.10)\times (1-0.35)=41.5\mathrm{\%}$

This means that any time the player deals bullet damage to any opponent (including denizens), they will immediately be healed by 41.5% of the damage dealt. Note that the in-game user interface is inconsistent in how it rounds the final lifesteal percentage.

Melee Lifesteal

Main articles: Melee Lifesteal, Lifestrike

Melee Lifesteal is not a stat. The item Melee Lifesteal and its upgrade Lifestrike both provide a passive ability which heals the user by a percentage of their melee damage dealt, but they behave differently from Bullet and Spirit Lifesteal. These abilities activate for one melee attack, then go on cooldown for several seconds, during which no further health can be regained from melee attacks; Bullet and Spirit Lifesteal are always active and have no associated cooldowns. These items also grant a flat healing bonus on activation, and are less effective against non-heroes, neither of which is true of Bullet and Spirit Lifesteal.

Spirit Lifesteal

Lifesteal is a mechanic which heals a player by a portion of the damage they deal to an opponent. There are two main types of lifesteal, each with an associated stat: Bullet Lifesteal, which returns a portion of the bullet damage dealt, and Spirit Lifesteal, which returns a portion of the spirit damage dealt. Bullet and Spirit Lifesteal are calculated identically, but are affected by different items.

Formula

Despite being presented in-game as +X% Bullet/Spirit Lifesteal, different sources of lifesteal stack multiplicatively, not additively. With $n$ different sources of the same category of lifesteal, final lifesteal $L_F$ is given by:

$L_F=1-\prod _{i=1}^n(1-L_i)$

where $L_i$ is the lifesteal provided by the $i$th source. Bullet and Spirit Lifesteal are calculated independently of each other, but both use the same formula.

Example

With 10% Bullet Lifesteal from Crippling Headshot and 35% Bullet Lifesteal from Leech, the player's final bullet lifesteal is:

$L_F=1-(1-0.10)\times (1-0.35)=41.5\mathrm{\%}$

This means that any time the player deals bullet damage to any opponent (including denizens), they will immediately be healed by 41.5% of the damage dealt. Note that the in-game user interface is inconsistent in how it rounds the final lifesteal percentage.

Melee Lifesteal

Main articles: Melee Lifesteal, Lifestrike

Melee Lifesteal is not a stat. The item Melee Lifesteal and its upgrade Lifestrike both provide a passive ability which heals the user by a percentage of their melee damage dealt, but they behave differently from Bullet and Spirit Lifesteal. These abilities activate for one melee attack, then go on cooldown for several seconds, during which no further health can be regained from melee attacks; Bullet and Spirit Lifesteal are always active and have no associated cooldowns. These items also grant a flat healing bonus on activation, and are less effective against non-heroes, neither of which is true of Bullet and Spirit Lifesteal.

Melee Lifesteal

Main articles: Melee Lifesteal, Lifestrike

Melee Lifesteal is not a stat. The item Melee Lifesteal and its upgrade Lifestrike both provide a passive ability which heals the user by a percentage of their melee damage dealt, but they behave differently from Bullet and Spirit Lifesteal. These abilities activate for one melee attack, then go on cooldown for several seconds, during which no further health can be regained from melee attacks; Bullet and Spirit Lifesteal are always active and have no associated cooldowns. These items also grant a flat healing bonus on activation, and are less effective against non-heroes, neither of which is true of Bullet and Spirit Lifesteal.