Damage

Damage Formula

((((Base Damage + Weapon/Magical Damage + Divine Strike Damage) * Impact Zone Bonus * Combo Bonus * (1 + Power Bonus)) + Additional Damage) * (1 + Hit Location Bonus) * (1 - (Damage Reduction * (1 - Penetration))) * (1 - Projectile Reduction)) + True Damage

Base Damage

• The displayed damage of a weapon, skill, or spell. For example: Rondel Dagger's 14 Weapon Damage, Rupture's 20 Physical Damage, or Judgement's 25 Magical Damage.

Weapon Damage

• The damage added by the "+ Weapon Damage" affix on gear. This stat benefits from Power Bonus. This stat will only apply to direct attacks from weaponry, and will not apply to skills such as Rupture, Caltrops, Achilles Strike, and so on. This is a Physical stat, and so will not add to sources of Magical Damage. This stat is influenced by Attribute Bonus Ratio.

Divine Strike Damage

• The damage added by the Cleric buff "Divine Strike". This stat benefits from Power Bonus. Unlike Weapon Damage, this stat will apply to any sources of Physical Damage. This is a Physical stat, and so will not add to sources of Magical Damage. This stat is influenced by Attribute Bonus Ratio.

Magical Damage

• The damage added by the "Magical Damage" stat on the Magic Staff, Spellbook, and Crystal Ball. This damage benefits from Power Bonus. This damage will apply to all sources of Magical Damage, and will do so multiple times per spell, if the spell has multiple damage sources. Examples include each hit of Magic Missile, or Zap's direct hit and DoT portions. This is a Magical stat, and so will not add to sources of Physical Damage. This stat is influenced by Attribute Bonus Ratio.

Impact Zone Bonus

• A multiplier enforced when hitting with the "sour spots" of certain weapons. See Weapons for each weapon's exact multipliers.

Combo Bonus

• A multiplier enforced when hitting with the latter hits of certain weapons' combos. See Weapons for each weapon's exact multipliers.

Power Bonus

• A multiplier that affects all damage types listed so far. This can be of the Physical or Magical variety, and each will only apply to its respective damage type (Physical Power Bonus will not apply to Zap, for example). This value can be positive or negative, and is influenced by gear or by the player's Attributes. This stat is influenced by Attribute Bonus Ratio.

Additional Damage

• The damage added by specific Perks or by the "Additional Physical/Magical Damage" affix on gear. This can be of the Physical or Magical variety, and each will only apply to its respective damage type (Additional Physical Damage will not apply to Zap, for example). This stat does not benefit from Power Bonus. This stat will apply to any instance of its respective type of damage, and will do so multiple times per skill if applicable. Examples include Achilles Strike's individual movement damage ticks (Physical), or each hit of Magic Missile (Magical). This stat is influenced by Attribute Bonus Ratio.

Hit Location Bonus

• A multiplier enforced when hitting the head or the limbs with certain attacks. This multiplier is 1.5x for headshots, and 0.5x for limb hits. This applies to all weapons, and selectively applies to some Magical Damage sources and not to others. Sources that are influenced include: Ice Bolt, Magic Missile, Fireball (Direct Hit Only), Ignite (Base AND DoT), Blow of Corruption. This does not apply to Physical skills, such as Achilles Strike.

Damage Reduction

• A defensive multiplier based on the opponent's Damage Reduction stat. Physical Damage Reduction applies to Physical Damage sources, such as weapon hits, Rupture, Achilles Strike, and so on. Magical Damage Reduction applies to Magical Damage sources, such as Zap, Explosive Bottles, Poison Weapon, and so on.

Penetration

• A modifier for Damage Reduction that can be acquired from certain weapons, or from the "Armor Penetration" or "Magical Penetration" affixes on gear. This stat multiplies with their Damage Reduction %, not their Armor Rating/Magic Resist Rating.

Projectile Reduction

• A defensive multiplier that can be acquired from Plate Armor, or the Projectile Resistance Perk for Fighter. This influences damage done by Arrows, Bolts, Throwables, and selectively applies to some Magical Damage sources and not to others. Sources that are influenced include: Ice Bolt, Magic Missile, and Fireball (Direct Hit).

True Damage

• The damage added by the "True Physical Damage" or "True Magical Damage" affixes on gear. Each will only apply to its respective damage type (True Magical Damage will not apply to an Arming Sword, for example). This damage is mostly unaffected by any other multipliers, and is added at the end of all calculations. This stat is influenced by Attribute Bonus Ratio.
• Cleric's Perseverance Perk is effectively "negative True Damage", however it seems to not reduce damage if that damage would be reduced below 1. For example, 1 stack of Rogue's Poison Weapon tends to deal less than 1 damage per second, and so Perseverance will not reduce it.

Notes

• Damage Over Time is usually calculated as a whole number at the start of the DoT, then divided by its duration. For example, +2 True Physical Damage would not add +2 damage to each tick of Rupture, but rather to the 20 total damage. This applies to DoTs that are debuffs specifically. Non-debuff DoTs such as Din of Darkness or Explosive Bottle flames, or movement-based DoTs such as Achilles Strike and Earthquake, are calculated per-tick.
• Weakpoint Attack's debuff multiplies the victim's Armor Rating directly. Because Armor Rating to Damage Reduction follows a variable curve, it is very difficult to predict how much this will influence damage.

Attribute Bonus Ratio

- "Attribute Bonus Ratio" is a hidden modifier present on a variety of spells, items, and skills. It will modify any sources of personal bonus damage/healing/shields/whatever else, based on its multiplier.

What does this include?

• Power Bonus (Magical and Physical)
• Magical Damage (From Spellbooks, Staves, and Crystal Balls)
• Divine Strike's special Physical Damage buff
• Additional Damage (Magical and Physical)
• True Damage (Magical and Physical)
• Weapon Damage (There is currently nothing implemented in the game with Attribute Bonus Ratio that can also benefit from standard Weapon Damage)
• Magical Healing

What does this not include?

• Location Bonus (Headshots, Limbs)
• Enemy Damage Reduction
• Projectile Reduction

- Here's an example using default Wizard's Ice Bolt. Ice Bolt has a base damage of 30, the default Magic Staff grants 5 Magical Damage, and Wizard's default Magic Power Bonus is 15%. This spell also benefits from Headshot Multiplier, which is 1.5x.

- Without Attribute Bonus Ratio, the damage calculation would look as follows:

( 30 + 5 ) * (1 + 0.15) * 1.5 = 60.375

- However, with Attribute Bonus Ratio of 50%, we must halve the +5 Magical Damage and the 15% Magic Power Bonus. Headshot multiplier is unaffected.

( 30 + 2.5 ) * (1 + 0.075) * 1.5 = 52.4063

What sources of damage are affected by this?

- Everything else that isn't in the following list can be assumed to be 100% scaling

50% Scaling:

• All Bard/Wizard/Cleric/Warlock spells/songs that either damage or heal, including direct hit, AoE, and damage over time, except Din of Darkness.
• Warlock's self-heal from Torture Mastery
• Barb's Achilles Strike movement ticks
• Rogue's Poison Weapon
• Rogue's Rupture
• Unique weapon Cinder's DoT
• Unique weapon Pestilence's DoT
• Explosive throwables
• Healing Potions & Troll's Blood
• Wizard's Arcane Shield

Other Scaling:

• Din of darkness (6%/9%/12% depending on song quality)

0% Scaling:

• Wizard Reactive Shield
• Protection Potions
• Cleric's Protection Spell
• Warlock perk Dark Reflection