Difference between revisions of "Guaranteed damage reduction"

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(Added gargoyle details, mentioned the benefits of lighter armours (EV), general clean up)
(Complete rewrite that doesn't make it sound like an extra effect on top of AC reduction)
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Wearing heavy body armour provides you with an amount of [[guaranteed damage reduction]] in melee combat. This is a percentage of an enemy's maximum possible damage output that you ignore from each of its hits. Because enemies rarely hit for their max damage, the GDR on some of the heaviest armours often reduces enemy damage to 0, and those hits that do get through are greatly reduced.
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Wearing any body armour with AC greater than 2 provides you with an amount of '''guaranteed damage reduction (GDR)''' in melee combat. Normally, each attack that hits you is reduced by a random amount up to your AC. GDR is a form of insurance against poor AC rolls; if you have sufficient AC, you are guaranteed to reduce the damage taken by a percentage of the enemy's maximum attack damage equal to your GDR. As an enemy's damage output is about as variable as your AC, a high GDR will allow you to completely negate an enemy's attacks much more often than normal, and those attacks that do get through will always be significantly diminished.
  
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Your GDR% = (14*(Body Armour Base AC-2)^(1/2))% (see chart below for exact figures with each armour). However, the amount of damage you can ignore this way is capped at one half of your total AC. While equipment in other slots, enchantments, and the Armour skill will raise your AC and thus raise the cap, your GDR% is only determined by the body armour you wear.
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==Calculating GDR==
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In most cases, your GDR% = (14*(Body Armour Base AC-2)^(1/2))%. No other type of armour provides any benefits to GDR.
  
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==What It Works Against==
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===GDR of Various Armours===
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GDR works against only one thing: physical damage from monsters attacking you in melee (including via a [[reaching]] brand). It does not work against any sort of ranged attack, be it from a physical launcher or a [[Conjurations]] spell that deals physical damage. Neither does it work against melee damage that is non-physical, such as an [[ice beast]]'s cold damage. However, most such elemental attacks need to do damage to you in the first place to trigger their added effects, so high GDR will make them happen less often.
 
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==GDR of Various Armours==
 
 
{| class="wikitable"
 
{| class="wikitable"
 
! Armour || Base AC || GDR
 
! Armour || Base AC || GDR
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|-
 
|-
 
|}
 
|}
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There are also two [[Transmutations]] spells which allow you to have GDR in spite of the fact that they effectively disable your body armour: [[Dragon Form]] (34%) and [[Statue Form]] (39%). Finally, [[gargoyle]] characters receive an innate boost to GDR. This boost is inversely proportional to the GDR provided by your body armour.
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==What GDR Affects==
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GDR only works against one thing: physical damage dealt by monsters attacking you in melee (including via a [[reaching]] brand). It does not work against any sort of ranged attack, be it from a physical launcher or a [[Conjurations]] spell that deals physical damage. Neither does it work against elemental melee damage, such as an [[ice beast]]'s cold damage. However, most such elemental attacks need to deal physical damage to you before their added effects trigger, so high GDR will make them happen less often.
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==Guaranteed Damage Reduction Cap==
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GDR is '''not''' a form of damage reduction separate from AC. If you have excellent GDR and terrible AC, it will do you no good. Regardless of your GDR%, you are only ''guaranteed'' an amount of damage reduction equal to 1/2 of your AC. If an enemy's damage roll exceeds this guaranteed minimum, the game tests the attack against your AC. If the damage reduction from AC winds up being greater than your guaranteed damage reduction, that is used instead.
  
 
==Strategy==
 
==Strategy==
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GDR is a very desirable property to have in your armour. It is a major reason for casters to consider wearing leather armour over a robe: 14% is a significant amount of guaranteed damage reduction. On the other hand, the powerful [[robe of the Archmagi|archmagi]] and [[Resistance (ego)|resistance]] brands are only found on robes, so the decision is not always clear-cut.
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GDR's usefulness depends heavily on how often you find yourself in melee combat, how high your AC is, and how much you're willing to sacrifice your [[ev]]asion defense (in general, the worse an armour is for your evasion, the higher its GDR will be). Unless you intend to wade into close combat whenever possible, ''and'' you have no intention of training [[Dodging]], you'll likely be better off avoiding super-heavy armour which maximizes GDR and focusing on optimizing your AC, EV, spells, and resistances to keep yourself alive. Characters that actively avoid melee, whether it be through fast movement speed or ranged attacks, will barely notice the effect of their GDR.
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For fighter types, GDR and high AC are the main reasons to go for heavier and heavier armours. If you aren't casting and are planning on training Armour, you should wear the first plate mail you find; the GDR is well worth the accuracy penalties, though the penalties to [[ev]]asion are significant. Later on, you might want to upgrade to a crystal plate mail or a gold dragon armour, though a branded, enchanted plate mail is a worthy ascension kit item as well. If you have a decent [[dexterity]] stat, switching to one of the medium-weight dragon armours can be a great choice as well; although you sacrifice some AC and GDR, the benefits from your [[Dodging]] skill will be much more noticeable.
 
  
 
==Example==  
 
==Example==  
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[[File:GDR_Example.png]]
 
[[File:GDR_Example.png]]
  
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This chart illustrates an important aspect of GDR: GDR best helps reduce damage from small and numerous attacks. When facing monsters that have a low max damage, you will take less damage with the higher GDR plate mail. For example, for a monster that has a max damage of 15, you will take on average 4.2 damage with the chain mail and 3.0 damage with the plate mail. So while you have a higher AC with the chain mail, you will be taking ''40% more'' damage, on average, than if you wore the plate mail.
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This chart illustrates an important aspect of GDR: GDR helps most when facing numerous small attacks. When facing monsters that have a low max damage, you will take less damage with the higher GDR plate mail. For example, for a monster that has a max damage of 15, you will take on average 4.2 damage with the chain mail and 3.0 damage with the plate mail. So while you have a higher AC with the chain mail, you will be taking ''40% more'' damage, on average, than if you wore the plate mail.
  
 
The higher AC only starts to overcome the better GDR when the max damage surpasses 50, but by then the difference in reduction is negligible.
 
The higher AC only starts to overcome the better GDR when the max damage surpasses 50, but by then the difference in reduction is negligible.
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==Other GDR Sources==
 
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There are two [[Transmutations]] spells which allow you to have GDR in spite of the fact that they effectively disable your body armour: [[Dragon Form]] (34%) and [[Statue Form]] (39%). Also, [[gargoyle]] characters receive an innate boost to GDR. This boost is inversely proportional to the GDR provided by your body armour.
 
  
 
[[Category:Defence]][[Category:Game mechanics]]
 
[[Category:Defence]][[Category:Game mechanics]]

Revision as of 02:38, 3 October 2013

Wearing any body armour with AC greater than 2 provides you with an amount of guaranteed damage reduction (GDR) in melee combat. Normally, each attack that hits you is reduced by a random amount up to your AC. GDR is a form of insurance against poor AC rolls; if you have sufficient AC, you are guaranteed to reduce the damage taken by a percentage of the enemy's maximum attack damage equal to your GDR. As an enemy's damage output is about as variable as your AC, a high GDR will allow you to completely negate an enemy's attacks much more often than normal, and those attacks that do get through will always be significantly diminished.

Calculating GDR

In most cases, your GDR% = (14*(Body Armour Base AC-2)^(1/2))%. No other type of armour provides any benefits to GDR.

GDR of Various Armours

Armour Base AC GDR
Robe, animal skin 2 0%
Leather armour 3 14%
Troll leather armour 4 19.79%
Ring mail, steam dragon armour 5 24.25%
Scale mail, mottled dragon armour 6 28%
Chain mail, swamp dragon armour 7 31.30%
Splint mail, fire dragon armour 8 34.29%
Ice dragon armour 9 37.04%
Plate mail, pearl dragon armour, storm dragon armour 10 39.60%
Gold dragon armour 12 44.27%
Crystal plate armour 14 48.50%

There are also two Transmutations spells which allow you to have GDR in spite of the fact that they effectively disable your body armour: Dragon Form (34%) and Statue Form (39%). Finally, gargoyle characters receive an innate boost to GDR. This boost is inversely proportional to the GDR provided by your body armour.

What GDR Affects

GDR only works against one thing: physical damage dealt by monsters attacking you in melee (including via a reaching brand). It does not work against any sort of ranged attack, be it from a physical launcher or a Conjurations spell that deals physical damage. Neither does it work against elemental melee damage, such as an ice beast's cold damage. However, most such elemental attacks need to deal physical damage to you before their added effects trigger, so high GDR will make them happen less often.

Guaranteed Damage Reduction Cap

GDR is not a form of damage reduction separate from AC. If you have excellent GDR and terrible AC, it will do you no good. Regardless of your GDR%, you are only guaranteed an amount of damage reduction equal to 1/2 of your AC. If an enemy's damage roll exceeds this guaranteed minimum, the game tests the attack against your AC. If the damage reduction from AC winds up being greater than your guaranteed damage reduction, that is used instead.

Strategy

GDR's usefulness depends heavily on how often you find yourself in melee combat, how high your AC is, and how much you're willing to sacrifice your evasion defense (in general, the worse an armour is for your evasion, the higher its GDR will be). Unless you intend to wade into close combat whenever possible, and you have no intention of training Dodging, you'll likely be better off avoiding super-heavy armour which maximizes GDR and focusing on optimizing your AC, EV, spells, and resistances to keep yourself alive. Characters that actively avoid melee, whether it be through fast movement speed or ranged attacks, will barely notice the effect of their GDR.

Example

When dealing with melee combat, 30 AC with a +6 chain mail is worse than 28 AC with a +0 plate mail.

The graph below lists the average damage taken after GDR calculations for a 28 AC plate vs a 30 AC chain. The plate has 40% damage reduction while the chain has 28% damage reduction. Note this omits the AC damage reduction check that can be greater than the GDR value.

GDR Example.png

This chart illustrates an important aspect of GDR: GDR helps most when facing numerous small attacks. When facing monsters that have a low max damage, you will take less damage with the higher GDR plate mail. For example, for a monster that has a max damage of 15, you will take on average 4.2 damage with the chain mail and 3.0 damage with the plate mail. So while you have a higher AC with the chain mail, you will be taking 40% more damage, on average, than if you wore the plate mail.

The higher AC only starts to overcome the better GDR when the max damage surpasses 50, but by then the difference in reduction is negligible.

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