Damage calculation

Damage in Guild Wars results from actions taken by attackers that subtract a portion of an defender's health. This definition includes many attacks or skills (including spells) but does not include health degeneration, life stealing, or sacrifices.

When an attacker attempts to damage a target, the following is factored in:
 * The damage type, such as Fire or Blunt. The amount of damage done may vary due to the defender's armor and resistances to that damage type.
 * The attacker's ability to inflict the damage.
 * The target's ability to resist this damage.
 * Bonuses on both side. An attacker may have bonuses that augment the damage and the target may have bonuses that reduce the damage.

Damage Types
There are many individual damage types, and two meaningful damage type categories, Elemental and Physical. * There is one case where Holy damage does not ignore armor. See below.

Damage Groups
It is useful to classify damage into damage groups (especially for PvP).
 * Spike damage
 * Damage over time

Effective Damage
''Note: For simplicity, on this page the term attack describes any attempt to damage an opponent. However, whenever the word "attack" is used in skill descriptions, it refers to the attack action.''

The Effective Damage (ED) depends on the Base Damage (BD), various Damage Modifiers (D*), and the Armor Effect (AE).


 * ED = [([BD &times; DEnhance &times; AE &times; DScale] + DShift) &times; DMult] + DNeg

For attacks that ignore armor, AE is removed from the equation (alternately, AE is set to 1).

Base Damage
Skill attacks has a specific base damage (BD) value indicated in the skill description.

Weapons attacks select BD each time uniformly from the damage range of the weapon. For weapons that have an attribute requirement on their damage range, there is actually another hidden range used for when the attacker does not meet the requirement. The hidden range is always lower than the display range, and varies randomly from weapon to weapon.

Damage Cap and Redirection
Certain enchantments will restrict the maximam damage the target can receive, or redirect some of the damage away from the target, thus making the received damage less than the Effective Damage. Cap is always applied before redirection.

The Exception - Judge's Insight
When calculating the holy damage resulting from Judge's Insight, treat it as light damage.

Illustrative Examples
[examples and graphs to be added]