Stat

Stats modify a single statistic of the game. Stats can apply to most aspects of the game, such as the player's character, items, monsters, skills or an area. Common sources of stats include modifiers, passive skills, buffs and skills.

Overview
Each stat has an internal ID (for example ) and a number of settings associated with it. Stats themselves do not have a value, their values are given by other sources such as modifiers or skills. The values are always integers and round downs to the nearest integer if the stat value is modified.

The ID and the values are used for translating the stat into a more human readable format, as such, stats may often appear in descriptions differently then they are used in game. This means they may omit information (i.e. values) or change their text and numbers to be more readable. For example the stat will appear as  for positive values and  for negative values on things that affect the player's character, but will appear as  and  on monsters respectively.

It is also possible that the description of a stat is omitted entirely and not visible to the player, however stats will still be effective. Very often this is the case for monster modifiers such as hidden item quantity or rarity boosts. This is also the case for stats that have a value of exactly 0.

Interaction
Stats will stack with themselves additively, so two or more stats with the same ID will simply be added up.

However, there is a distinction between Global and Local stats:
 * Local stats will only be added to the relevant source.
 * Global stats are applied globally as the name suggests.

Stats with different IDs may also interact with each other, however there is no dead set rule on how different stats interact with each other. Often the interaction can be derived from the description of the stats.

Rule of thumb based on descriptions
The visible description generally hints at a few rules for the interaction. However be wary there may be edge cases where it behaves differently.

Flat, additive and multiplicative stats

 * Flat stats usually use a form of the the word . They stack additively with other flat stats of the same scope. Resistances are flat stats which use the word and are represented as percentages, and so are notable exceptions to the general rules.
 * Additive stats are usually percentages and use forms of the the words or . They are summed with other additive stats of the same scope.
 * Multiplicative stats are usually percentages and use forms of the words or . They stack multiplicatively with other multiplicative stats of the same scope. A multiplicative stat's internal ID can usually be identified by the suffix "_final".

What this means in plain English is that you add the various "increased"/"reduced" effects together into a single multiplier, and multiply the base stat by the result, whereas you multiply the base stat by each "more"/"less" effect in turn.

Also see the example section below.

Order of application
Stats are only applied once per calculation. The usual order of application is:
 * 1) Local flat stats
 * 2) Local additive and multiplicative stats
 * 3) Global and skill flat stats
 * 4) Global and skill additive stats
 * 5) Global and skill multiplicative stats

Tip: Assuming equal values, "more" is usually far more powerful than increased.

Applicability from other sources
Often a stat has a set of types determining to which statistics it applies. Types can be subtypes or supertypes of other Types. Supertypes affect their subtypes but not vice versa. Many types correspond to Gem Tags; however, this relationship is not strict. For example, has the Melee tag, but its projectiles do not do melee damage, and  has the Attack tag, but the charge detonation does not do Attack damage.

Some words have special meanings:


 * If a stat specifies only one Type, or if the word is used to combine multiple Types, then the stat applies to any combination of the Types. For example,  affects armour, or energy shield, or both armour and energy shield.
 * If a stat specifies multiple Types not combined using the word, then it only applies to all of the Types together. For example, would not affect non-elemental damage with maces, nor non-damage elemental effects with maces, nor elemental damage not dealt with maces.
 * If the word is used in conjunction with an item Type, the stat is effective globally whether the statistic applies directly to the item or not. For example,  would apply to spells cast while wielding a staff, even though the staff is not involved in the casting of spells.
 * If the word is used in conjunction with an item Type, the stat is effective only when that item is being directly used. For example,  would only affect attacks made with the claws themselves.

Converted statistics count as both the Type converted from and converted to, but can only be affected by a particular stat at most once.

Effectiveness of stacking stat values
The following applies to most statistics that can be stacked, as it's a side effect of the linearity of the stats.

From the general interactions it is possible to derive some basic rules for the effectiveness of stacking stats:
 * Stats that will stack towards infinity will become less effective per point as you increase them (diminishing return)
 * Stats that will stack towards zero will become more effective per point as you decrease them (slippery slope)

Remember that some stats have altered descriptions and in reality often values behave differently from what is shown. A good example are resistances - it is better to think of them as damage reduction in this case (75% being 75% less damage, aka a 0.25 multiplier).

Rule of thumb
For increased and more modifiers, they generally scale as:

$1+{x \over 100}$

Similarly, for the reduction:

more vs increased
You have 1000 base damage and from gear and  from passives. You can then choose between slotting either of two support gems:

Gem A gives.

Gem B gives.

Calculation:

Gem A: gear+passive+gem = 300% increased, so 1000*(1+3.0) = 4000 damage.

Gem B: (gear+passive)*gem = 200% increased and 100% more, so 1000*(1+2.0)*(1+1.0) = 6000 dmg

is equivalent to "increased" (but getting smaller instead of larger); likewise works in the equivalent way as "more".

Global stats
If you have
 * 3x from the Passive Skill Tree
 * from Equipment
 * your Character starts with

You will get:


 * total

Local stats
Assume you are dual wielding two one-handed melee weapons.

On each of the weapons, you have rolled the modifiers and  at their maximum value, which grant the following respectively:
 * and
 * and

On each weapon, you will get a total of:

However, as you can see the stats from each weapon will not add up, because they're local to each weapon.

Interaction of flat, additive, multiplicative stats and conversion
For this example, we assume the following:
 * 75-75 Physical Damage from our weapon
 * Local stats on the weapon:
 * Local stat on the weapon:
 * Global stat:
 * Global stat:
 * Skill stat: (i.e. from  or )

First the local stats are applied:
 * 75-75 Physical Damage +25 min, +25 max
 * 100-100 Physical Damage *2 (i.e. +100%))
 * 200-200 Physical Damage

Method A: Stats first
Adding the global physical damage increase:
 * 200-200 Physical *2 (i.e. +100%)
 * 400-400 Physical

In the next step, damage conversion. Broken down into two individual branches

Branch 1 (Physical)
 * 400-400 Physical Damage *0.5 (i.e. 50% non-converted damage)
 * 200-200 Physical Damage

Branch 2 (Lightning)
 * 400-400 Physical Damage *0.5 (i.e. 50% converted damage)
 * 200-200 Lightning Damage * 3/2 (i.e. in a prior step, we already applied a increased stat of 100% (/2). We apply another 100% on top of the other 100%, for a total of 200% (*3))
 * 300-300 Lightning Damage

Total
 * 200-200 Physical 300-300 Lightning Damage

Method B: Conversion first
We break it down into two branches right away:

Branch 1 (Physical)
 * 200-200 Physical Damage * 0.5 (i.e. 50% non-converted damage)
 * 100-100 Physical Damage * 2 (i.e. 100% increased Physical Damage)
 * 200-200 Physical Damage

Branch 2 (Lightning)
 * 200-200 Physical Damage * 0.5 (i.e. 50% converted damage)
 * 100-100 Lightning Damage * 3 (100% increased Physical + 100% increased Lighting -> 200%)
 * 300-300 Lightning Damage

Total
 * 200-200 Physical 300-300 Lightning Damage