Damage factor

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A damage factor (DF) is a numerical representation of the effectiveness of a weapon or spell against one of the five armor groups.

Weapon or Bolt

Generally, a weapon or bolt will have a damage factor of less than 1.0 expressed as three decimal places. The DF, in combination with an attack's endroll, determines the amount of base damage sustained by a target. For a successful attack the endroll must be greater than 100. Base damage is calculated from the expression (damage factor * endroll success margin) with the endroll success margin (ESM) defined as the endroll - 100.

As an example, an attack is made with a broadsword against a target wearing double leather, a member of the leather armor group. The broadsword's damage factor vs leather is .300 as seen in the table below. Assuming that the attack resulted in an endroll of 150 (ESM 50), we can now calculate the base damage as (DF .300 * ESM 50) = 15. If the target was wearing plate class armor the base damage would be (DF .200 * ESM 50) = 10.

In addition to base damage, attacks will often result in critical damage. Base damage along with several other factors determines the critical damage. Base damage plus critical damage equals the total damage taken (measured in hitpoints) from an attack.

Note: Use normal rounding for base damage calculations. The exception to this is when the damage is less than .5. In this instance damage rounds up to 1.

Sample Weapon Damage Factor Table

Weapon AG Cloth Leather Scale Chain Plate RT Min RT Damage Type STR/DU
AsG 1 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Broadsword DF .450 .300 .250 .225 .200 5 4 Slash/Puncture/Crush 75/160
AvD 36 36 35 34 33 36 34 32 30 37 33 29 25 36 30 24 18

For weapon damage factors by type, see Edged Weapons, Blunt Weapons, Polearm Weapons, Ranged Weapons, Two-Handed Weapons, Brawling, and Thrown Weapons. For bolt spell DFs, see Bolt spells.

Unarmed Combat System

Each type of unarmed attack (Jab, Punch, Kick, Grapple) has damage factors against different armor groups, which are then multiplied with the endroll success margin to determine base damage and critical range. See the UCS article for more details.


Direct damage warding spells typically use a hidden damage factor that is multiplied with the endroll success margin (also known in these cases as the warding margin) to resolve both concussion and critical damage cycles, but the exact formulas can vary widely depending on the spell.