The purpose of this article is to provide knowledge for powergamers, from powergamers, and to convert casual players into even more powergamers. We like having all relevant information easily available in one place without the need to hack'n'slash through the entire Internet to find it.
While most skill to play a game even as complex as Diablo III can be acquired simply by playing the game, some aspects of it are nearly impossible for a human to comprehend perfectly just by playing. Powergaming is an applied science of theorycrafting, and like any applied science, one must master the theory behind it in order to excel in practice.
The most reliable source we're using when creating this article is testing in the game itself (we both have access to Diablo III beta). Whenever we write about something we can't properly test, we're using as many different sources as is needed to become convinced of its factuality. Once we've convinced ourselves, we can feel comfortable with sharing the knowledge with every other Diablo III fanatic out there.
Table of Contents
All damage skills refer to your character's weapon damage. Compared to other games, this was changed from the old paradigm of spell damage being calculated differently from physical damage.
Weapon damage refers to the damage your weapon does after being multiplied by your primary stat and other bonuses, not just the damage that's displayed in the weapon's tooltip. When referring to just the damage on a weapon item's tooltip, we'll use the term base weapon damage. The Damage value on your character screen displays your damage per second (DPS), which is calculated as:
damage per second = weapon damage × attacks per second
To calculate how much damage a hit will do to the target after all modifiers have been taken in account, the following formula can be used. All damage increasing bonuses stack multiplicatively with weapon damage and primary stat modifier.
total damage per hit = (base weapon damage × skill damage) × (1 + primary stat / 100) × (1 + first damage bonus) × (1 + second other damage bonus etc) × (1 + monster vulnerability bonuses)
Example 1: Wendy the Wizard has a wand that deals 33 base weapon damage. In addition, Wendy also has 123 intellect, which increases her damage by 123%, and the Glass Cannon passive skill, which gives her a 15% damage bonus. There are no damage increasing vulnerability effects on the monster so we can ignore that.
The tooltip for Magic Missile says, "Launch a missile of magic energy, causing 110% weapon damage as Arcane."
The total damage for each Magic Missile hit is calculated like this:
33 × 110% × (1 + 1.23) × 1.15 ≈ 93.091 damage per hit
Please note: All the damage and speed modifiers on a weapon are already calcualted and displayed on the tooltip. This includes +x-y damage, +x% damage, and +x% IAS
Attack speed, or Attacks per Second (APS) simply means how often your character can use its skills. APS can be converted into time between attacks by dividing 1 by it:
time between attacks = 1 / attacks per second
Most skills work based on your character's attack speed. Notice that the skill tooltip doesn't usually say anything about attack speed, and even though most skills use your attack speed as it is, there are some exceptions.
Example 1: Wendy's wand deals 1.20 attacks per second. She'll be able to shoot one Magic Missile once every 1 / 1.20 ≈ 0.833 seconds.
Please note: All the damage and speed modifiers on a weapon are already calcualted and displayed on the tooltip. This includes +x-y damage, +x% damage, and +x% IAS
When your attack speed is increased, the math involved gets a little unintuitive. All attack speed modifiers stack additively, not multiplicatively. Your total attacks per second value is calcualted like this:
attacks per second = weapon tooltip attacks per second × (1 + dual wield bonus + other gear and skill attack speed bonuses)
Example 1: Barry the Barbarian is dual wielding weapons with 1.40 attacks per second. For simplicity's sake, we'll use the same speed on each hand. For dual wielding, Barry gets the 15% increased attack speed (IAS) bonus. In addition, Barry has 11% IAS from gear, and 3% from the Enchantress' Focused Mind aura. Barry's total attacks per second value will be:
1.40 × (1 + 0.15 + 0.11 + 0.03) = 1.40 × 1.29 = 1.806 attacks per second
Example 2: In addition to Example 1, Barry also has a stack of Frenzy buff which gives him 75% increased attack speed. The 75% is added to the other modifiers before anything gets multiplied. Barry's new attack speed with Frenzy is:
1.40 × (1 + 0.15 + 0.11 + 0.03 + 0.75) = 1.40 × 2.04 = 2.856 attacks per second
This is only 2.856 / 1.806 ≈ 1.581 times as fast, or rather 58.1% faster than without Frenzy (instead of 75% like the Frenzy skill suggests). When you already have some increased attack speed bonuses active, the further ones don't let you attack as much more often as the percentage shows. This design is required to keep the absolute DPS increase of one IAS the same no matter how much IAS you already have. Otherwise IAS would become the better the more IAS you already have.
Critical Hit Chance tells how often your character lands a critical hit instead of a regular hit. If your critical hit chance is 10%, an average of 10% of your attacks are critical hits.
Critical Hit Damage tells how much more damage an attack causes if it's critical. If your critical hit damage is 50%, when you critically hit, the total damage of the attack is increased by 50% (to 150% of the original damage). Critical hit damage bonus is applied after every other damage increasing effect.
Monk, Barbarian, and Demon Hunter can dual wield certain one-handed weapons. When dual wielding, the character takes turns hitting with each hand with most skills. There's an added benefit of gaining +15% Increased Attack Speed bonus to make dual wielding better DPS than simply using single one handed weapon with a shield. Also keep in mind that weapons (also Wizard Orbs and WD Wanga Dolls) tend to have some offensive stats in them, compared to the more defensively oriented shields.
To break this rule, there are some powerful skills, either with a large resource cost or long cooldown, that always calculate damage based on your main hand weapon. Some examples of these are Monk skills Cyclone Strike and Wave of Light. Blizzard is yet to confirm which skills work like this so until then more testing by players is needed.
It's easy to think that the DPS of your weapons should be within the 15% DW bonus of eachother or the weaker off-hand starts to contribute negatively to your DPS. The exact percentage is about 74%: If both of your weapons have the same attack speed, but one of them has only 74% DPS compared to the other, the difference cancels out the 15% dual wield IAS bonus and you'd be better off using a shield.
There's an exception to this though: If your off-hand weapon has high enough attack speed, its DPS can be below this threshold and still contribute positively to total DPS. It's easy to imagine like this:
Let's assume the DPS of your off-hand weapon is very close to zero, but its time between attacks is also very close to zero. You'll spend almost all of your time swinging the main-hand weapon that gets the 15% dual wield benefit, and the DPS of the off-hand becomes insignificant.
Dual wield DPS can be calculated like this:
dual wield dps = 1.15 × (main-hand damage + off-hand damage) / ((1 / main-hand attacks per second) + (1 / off-hand attacks per second))
dual wield dps = 1.15 × (main-hand damage + off-hand damage) / (main-hand time between attacks + off-hand time between attacks)
Haunt is a textbook example of a damage over time skill, DOT for short. When you cast a DOT, it will afflict the target for the specified duration, dealing the specified amount of damage over the whole duration of the skill. The damage is dealt continuously, little by little, but shown as combat text only every half a second, with rounded numbers.
Casting another application of certain DOT by same player on same target doesn't stack, it only refreshes the duration. However same DOTs by different casters do stack on same target.
Example 1: William the Witch Doctor is using the aforementioned Haunt, dealing 575% weapon damage over 15 seconds. William's weapon hits for 500 damage. Over its whole duration, his Haunt will deal 575% × 500 = 2875 damage, or 2875 / 15 = 191.67 dps
When you channel a skill with a continuous effect such as Disintegrate, it will deal damage based on cycles, which are equal in length to your swing speed, that is 1/APS value. The damage is calculated based on those cycles, then spread over the whole cycle duration so that it's dealt to the target continuously instead of once every cycle. Just as with DOTs, damage is shown as combat text every half a second, with rounded numbers.
A thing worth pointing out is that channeled skills deal same dps (when weapon's dps stays constant) over time no matter the weapon's speed. Their cost on the other hand is paid per attack cycle, therefore making faster weapons burn your resources at a higher rate compared to a slow one. As Wizard and Witch Doctor are the main users of channeled spells, and they do not have access to real resource generator abilities like the other classes' Primary Skills, considering weapon speed is of utmost importance for their resource management. This is really no different to any other skills, but people might find the continuous nature of channeled skills confusing.
Example 1: Wendy the Wizard has found a bow with base damage of 43 and 1.40 attacks per second. She has no other damage increasing stats. Wendy starts channeling Disintegrate. During the first 1/1.40 = 0.71 seconds, Disintegrate causes 43 × 155% = 66.65 damage, and you can see the enemy's health bar continuously decreasing during that time instead of jumping down between every cycle.
Wendy continues channeling, and stops after exactly 3.5 seconds from the beginning. During these 3.5 seconds, Wendy has had time for 3.5 × 1.40 = 4.9 Disintegrate cycles, which means the total damage caused by the Disintegrate is 43 × 155% × 4.9 = 326.585
Some channeled skills, such as Rapid Fire, don't have a continuous effect, but instead launch projectiles periodically. Here the principle is otherwise the same, but the damage of every cycle is divided equally among all projectiles launched during that cycle.
Over time, channeled skills work like any other spammable skill. They're simply made work continuously for flavour reasons, so that you can cast those laser beams and flame throwers in bursts of duration of your choosing rather than be restricted by attack speed cycles.
The chapters above work perfectly well for spammable 'main attack' type of skills, even in combinations of gainers and spenders. These skills are over time neutral to weapon speed, since with faster weapons you both generate and use resources at a faster pace.
With a weapon of 100 dps 1 APS thus 100 damage per hit, the above rotation results in 5 × 150% × 100 + 1 × 200% × 100 = 950 damage over 6 seconds, or 950 / 6 = 158 dps.
If we change the speed of the weapon above to 2APS and damage per hit to 50, dps would remain the same at 100. Now a rotation of 5 Bashes and one Hammer takes 3 seconds. Let's calculate the dps for that rotation: (5 × 150% × 50 + 1 × 200% × 50) / 3 = 158 dps.
Example 2: Now that we have established that dps for the Bash × 5 + Hammer rotation is independent of weapon speed, let's see what happens when we add Earthquake to the mix. Let's assume Earthquake follows the same rules as any attack, inheriting APS and weapon damage per hit of your weapon.
Note: this paragraph illustrates a scenario that is incorrect. With the first weapon the player would drop a quake that lasts for 8 seconds in 1 second, continuing his base dps of 158 for the remaining 7 seconds. Earthquake deals 2000% × 100 / 8 = 250 dps over its duration with weapon number one, for a total dps for the 8 second span being 250 + 7/8 × 158 = 388 dps
This is how it really works: Let's change to the faster weapon again. Earthquake numbers become 2000% × 50 / 8 = 125 dps over its duration 2 APS 100 dps weapon, for a total dps for the 8 second span being 125 + 15/16 × 158 = 273 dps
The above has been tested in beta by multiple people including us using Grasp of the Dead. Its weapon damage multiplier shown in tooltip gets multiplied by your APS for the final damage calculation. In other words, the multiplier applies to your dps, not damage per hit value.
There is reason for this is those skills can't be spammed indefinitely so attack speeds and resource management would 'cancel out' resulting in same eventual dps. If skills with cooldown used straight weapon damage they would reap massive benefits from slow 2-handers, rendering the skills either useless for DW or overpowered for 2-handers.
To go with their neutrality towards hit damage/dps, these skills also seem to have a fixed casting time independent of your APS. This might vary per skill and class, Superstate puts it at 1.2 seconds for most Barbarian abilities that aren't primary spenders or generators.
Based on the same reasoning and tests as in above chapter, pets also inherit their stats based on your weapon dps, not damage per hit. Refer to the source link for more information, look especially for posts by HardRock and Superstate.
When using weapons imbued with elemental damage, for the most part, attacks only cause visual and audio cues towards the kind of element in question. Early in development, there was an idea that critical strikes would cause some special effects, but this is no longer true.
Cold damage has a chance of applying a snare that slows down the target's movement speed for a short duration of time. Cold damage affixes have a lower damage range compared to others to compensate for this bonus.
Poison is simply another elemental damage type, with no special effects associated with it. It is not always (but can be) a DOT effect like it always is in Diablo II.
We'll start going through the defensive statistics of Diablo 3 in intuitive order of first rolling for dodge, which has a chance to negate a hit completely. In the end there's blocking, which gives a chance of reducing the eventual damage you would get from a hit by a flat value. Between those all percentage based damage reduction effects take place, stacking multiplicatively.
Dodge gives you a chance to avoid getting hit by an attack altogether. From hit re solution perspective you can think of the dodge check as the first stage. If the dodge is successfull, hit resolution might as well stop right there.
Dodge works on basically everything. You can dodge melee hits, missiles, spells, aoe hits, passive damage from environment, and so on.
Characters have zero base chance to dodge. Neither are there any pure dodge bonuses from gear, so Dexterity is the main source of Dodge for all characters. Characters always have at least some amount of Dexterity, which will convert to a slight chance to dodge. The dodge per dexterity conversion has several thresholds where the conversion rate changes dramatically, possibly encouraging players to reach some of these dodge break points.
|Dex range||Dodge% per point of Dex|
|1 - 100||0.100|
|101 - 500||0.025|
|501 - 1000||0.020|
|1001 - 8000||0.010|
According to above table, 8000 Dex would result in 100% chance to dodge.
Example 1: Marty the Monk has 321 Dexterity from gear. The first 100 dexterity give him 0.1% chance to dodge each, for 10% overall. The rest fall within the 101-500 boundary, for an addition of 221 × 0.025 = 5.525%
His total chance to dodge would thus be 10% + 5.525% = 15.525%
Dodge from different sources stacks with itself multiplicatively. Different sources for this purpose would be for example dodge from Dexterity, and dodge from Mantra of Evasion, you don't get to add these together.
Example 2: Marty activates Mantra of Evasion in addition to his 15.525% Dodge from Dexterity. His total chance to dodge would not be 15% + 15.525% = 30.525%, but rather 1 - ((1-0.15) × (1-0.15525)) = 28.20%
When the character panel refers to Damage Reduction, it only shows what you gain from armor. In this compilation we handle both armor and resistances under the same title since they works almost exactly the same way, and both of then reduce damage.
Armor reduces all damage you would suffer by a percentage. Resistances work the same way, though each for their own designated damage types. Notice that armor works for magical damage as well, and that there is a separate Physical Resistance stat.
It doesn't matter in which order these reductions are applied, since they are all multiplicative.
Each piece or armor your character wears increases your armor by a certain value. Higher level items will provide a higher amount of armor. Wearing a shield will increase your armor by a noticeable margin.
All classes receive extra armor based on their Strength statistic, for 1 armor per 1 point of Str. Many classes also have skills that increase their Armor by either a flat value or percentage.
The way character panel shows damage reduction from armor is against a monster of same level as the player. Hence you will never know your true damage reduction percentage against Inferno monsters by consulting the character screen. Below is the formula used for calculating your damage reduction from armor against a monster of any level.
Example 1: Barry the Barbarian is fighting level 63 monsters in Inferno. He has 3000 Armor which equates to 3000 / (50 × 63 + 3000) = 48.7% damage reduction
Example 2: Barry feels he's taking too much damage and equips a shield to increase his armor. The shield gives 1000 extra Armor, putting Barry at 4000 / (50 × 63 + 4000) = 55.9% damage reduction. Much better!
Equipping a shield would also give Barry a chance to block incoming hits.
All classes receive bonuses to all resistances from their Intelligence statistic, for 0.1 resistance per 1 point of Int. Formula for resistance calculations below:
There is a separate statistic for physical damage. All classes always have at least some amount of Intelligence to provide bonus all resistances, so there is a small but noticeable reduction to 'normal' physical hits due to this in addition to Armor.
Because Barbarians and Monks
are so awesome tend to always be in the face of danger, getting pounded by monsters in order to hit them themselves, they have an additional 30% damage reduction from all sources.
To have a chance to block, you naturally need to be wearing a shield. There is no innate blocking skill, everything you have is what you get from the shield you have equipped, and possibly from other armor. There are no skills that require the usage of a shield, neither are there abilities that give bonuses to blocking. It's completely up to you if you want the defensive boost from the armor increase and chance to block, versus dual wielding or using a two-handed weapon, Blizzard doesn't want to guide this decision based on available abilities.
For hits that you didn't dodge, you have an additional chance to avoid a portion of the damage if you wear a shield. The highest level craftables, Exalted Grand Dread Shields, can spawn with 10.00-20.00% chance to block. There are several affixes that can increase your block chance.
Just like block chance, the value by which a blocked hit is reduced is greatly dependent of the shield you are using. To use the Grand Exalted Dread Shield as an example again, it can spawn with 2795-3705 block amount. This reduction for blocked value is the final modifier that may be subtracted from a hit, in other words all damage reduction by armor, resistances, and other effects happen before blocking.
This modifier makes you recover from crowd control effects such as fear and stun faster. On normal difficulty level the stated value should work exactly as advertised. If you have 20% CC reduction, it should make the CC last for (1 - 0.20) × Base Duration. This probably stacks like dodge and damage reduction, each further source reducing what is left over from other sources, so 15% and 25% of this stat would leave you with total reduction of 1 - ((1-0.15) × (1-0.25)) = 36.25%.
RESEARCH NEEDED: How exactly it is calculated, and if the effect is diminished on harder difficulties harder difficulties.
Stun from Ground Stomp has duration of 70% from stated 4 seconds on elite monsters and Skeleton King on beta. Blizzard have stated that crowd control effects will get less effective on harder difficulties. Remains to be tested how much the reduction is on Nightmare, Hell and Inferno.
Each class starts the game with 110 Life. This comes from 36 base life, 4 × level = 4 bonus from level, and 10 × 7 bonus from having 7 starting Vitality. Thus the formula for calculating the life of any character is:
Life when player level < 35: = 36 + 4 × Level + 10 × Vitality
Life when player level ≥ 35: = 36 + 4 × Level + (Level - 25) × Vitality
Knowing your pure hit points value isn't usually very useful though, since you'll be wearing armor and benefiting from other damage reducing effects. Often players talk about a value called Effective Hit Points instead.100 / (1 - 0.25) = 133 EHP. A more thorough formula would be:
EHP: = Life / ((1 - DR from Armor) × (1 - DR from Resistance) × (1 - 0.30 if monk or barbarian) × (1 - DR from other source))
If we take the formulas for DR from Armor and Resistances from earlier, and plug them into the above calculation, it becomes
EHP: = Life × ((1 + Armor / (50 × Monster Level)) × (1 + Resistance / (5 × Monster Level)))
This function scales linearly with both Resistances and Armor, meaning each additional X armor will increase your effective health as much as the previous similar addition.
Some people argue that dodge should be included in EHP calculations as another form of damage reduction. This can have merit when dealing with damage sources that simply cannot kill you in meaningful number of hits. As soon as few unavoided hits can threaten your survival, this approach is rendered useless. Dodge and block are important for regulating incoming damage over long periods of time, but cannot be taken into calculations at face value since they work on chance basis, not all the time.
As always with theorycrafting, you should consider your personal situation, and make calculations and predictions based on your exact needs, not because someone somewhere on the internet says "do this".
This multiplier is applied after all other Life enhancing bonuses. Multiple sources of this modifier stack additively with eachother, so if you have +15% total life from one source and +10% from another, your real life total will be Original Life × (1 + 0.15 + 0.10) = 1.25 × Original Life
There should not be anything special or difficult going on with this stat. Does exactly what it says.
Life Steal is reduced to 20% effectivity on Inferno. However it is not affected by which skill you use.
Should be nothing special here.
Life per Hit modifier is normalized per average expected number of targets hit by the attack. That is, for using aoe skill on multiple monsters, you'll proc this for about as much as for using a single target skill on a single monster. Check the links below for good estimates for Wizards and Barbarian skills, and extrapolate for your own class!
A great way to gain more mileage from your Life per Hit items is to increase your attack speed, making this modifier proc more often. This obviously works for Life Steal too through increased damage, but the flat values of Life per Hit items can be noticeably higher than whatever the percentage from Life Steal items usually provide.
Should be nothing special here. Healing received from health gloves is increased by the displayed number.
Should be nothing special here except the ingame yards are more like feet compared to the player character. We'll add a picture illustrating the distances soon, didn't have any good screenshots from beta for that.
Each class has a unique resource system they use for powering abilities. Demon Hunter even has two resources at her disposal at the same time! The resource pools are varyingly sized, and the means and rate they regenerate also differ.
Resource pool: 100, starts at 0 in each game
Degeneration: -2 per second after 10 second delay
Barbarian's primary attacks and most utility skills generate Fury, which is used to pay for his more powerful attacks. Since fury degenerates while not fighting, constant fury generation is important. Hence barbarians can build Fury by striking urns and other objects with their primary skills.
The class starts each game with 0 fury, and the resource begins to diminish at rate of 2 per second 10 seconds after you stop fighting. Fighting encompasses hitting a monster or object with either spender or generator attacks. Even getting hit by monsters yourself generates some fury and stops the degeneration. The key is either dealing or receiving damage, performing attacks on thin air doesn't stop this effect.
Resource pool: 125, starts at maximum in each game
Regeneration: +4 per second
Hatred is the resource involved in Demon Hunter's conventional attacks, like shooting different kinds of arrows. Primary skills generate Hatred, and more powerful attacks are paid for by spending it. Demon Hunter's Hatred grows with time at a rate of 4 Hatred per second, up to a maximum of 125. Unlike Barbarian's Fury and Monk's Spirit, Hatred can be generated by using generator attacks even without a target.
Resource pool: 30, starts at maximum in each game
Regeneration: +1 per second
Discipline is mostly reserved for Demon Hunter's utility skills, like increased mobility and traps. Discipline regenerates passively at a rate of 1 per second. There are no Discipline generating abilities, except Preparation which restores your whole Discipline pool but has a long cooldown, and some skill runes that give a chance to generate Discipline when using the skill.
Resource pool: 150, starts at maximum in each game
Regeneration: +0 per second, can be increased with skills
Monks start each game with a full globe of Spirit. By default, Spirit doesn't regenerate by itself, so attacking with a primary skill is needed to replenish the pool upon depletion. Monks only gain Spirit by hitting enemies, not from breaking destructible objects.
Monk's spirit spender abilities are designed to be more costly than those of other classes. This is balanced by making their generators more versatile in comparison.
The maximum Spirit for Monk is 150 by default, but can be increased to 250 with the Exalted Soul passive skill. By default, monks have zero Spirit regeneration, but have skills to increase it: Chant of resonance, and Mantra of Healing runed with Circular Breathing.
Resource pool: Level dependant, starts at maximum in each game
Regeneration: Level dependant (precise calculations will be provided later)
Witch Doctor is the only class to use the traditional caster resource, Mana. His mana pool is numerically larger than the percentage-like meters the other classes have, to give that proper oldschool feel. Since mana pool grows with time, mana costs for WD spells also scale based on character level. Skill calculators show the level 60 costs for each skill. Mana regeneration speed is set so that you keep replenishing your pool faster than spamming the cheapest spells drains it.
Resource pool: 100, starts at maximum in each game
Regeneration: +10 per second
Wizard's Arcane Power (AP) regenerates rapidly back to its maximum after use. Her primary skills, labeled Signature Spells, don't cost any AP to cast. They can even be runed to grant you some extra when cast, to facilitate faster recovery of AP.
Movement Speed bonuses make your character run faster. There are two categories of movement speed bonuses, static and temporary. The static bonus is restricted to 25%, you can't permanently raise your movement speed above that. It is possible with skills slike Sprint though. The passive bonuses stack additively, up to the 25% limit.
Temporary effects like Sprint multiply this passive speed you have by their own modifiers.
Notice that Skills like Vault and Leap don't care about your movement speed since they simply relocate the character from starting point to destination. IAS bonuses however make those abilities perform faster, increasing your overall speed a little.
Only the most powerful movement speed reducing effect per target takes place. When its duration runs out, the snare reverts to any potential weaker but longer lasting slowing effects.
Gold Find is averaged between each group member when playing in a group. Gold Find works linearly, just as you would expect from a percentage based modifier. It won't make gold drop more often, rather increases the size of each gold pile found. This has been tested on beta.
Magic Find, just like Gold Find, is averaged between each group member when playing in a group. It is currently unknown exactly how Magic Find bonus works. At least in the low end of spectrum, it probably isn't very far from linear. A lot of people are running around switching to a high MF set just before a boss kill, I guess someone has seen it produce results.
Bashiok gave the following 'answer' when questioned about MF scaling:
Well I don't think it's a linear scale, if that's what you mean. We might share what it is on our game guide sometime after launch.
Nephalem Valor is a buff that becomes active for level 60 players when killing Champion or Rare monsters. Champions(blue name) always spawn as a group of 3 to 4 while Rare monsters (yellow name) have randomly generated name and less powerful minions. When you kill these monsters, you get a stacking buff that increases both gold and magic find bonuses by 15% each. As long as you find another such group, the buff keeps refreshing and stacking for higher bonus, for a maximum of 5 stacks.
The motive behind this system is to keep players from switching skills all the time and show some commitment to a build — if you change a skill, your Nephalem Valor bonus drops off. Changing equipment retains the buff though.
Before 1.0.3 a 5 stack of Nephalem Valor used to give two extra rare drops from bosses. It has now been changed to one guaranteed extra drop from bosses, and one guaranteed extra rare drop from Champions and Rares to discourage people from quitting the run after a boss is dead, rather roaming around more finding even further elites to kill.
You get drastically diminished experience gains from killing monsters lower level than yourself. This was easily noticeable in beta as soon as you levelled over the intended level range for the content, and grinding through levels 10-13 was really slow. On the other hand for monsters of higher level you get some bonus experience. The following table demonstrates how experience gains are adjusted based on character's and monsters'level difference. You get no experience from killing monsters 10 or more levels lower than yourself.
|Monster level compared to character level||XP gain|
|3 levels higher and above||125%|
|2 levels higher||120%|
|1 level higher||115%|
|Same level monster||100%|
|1 level lower||90%|
|2 levels lower||80%|
|3 levels lower||70%|
|4 levels lower||60%|
|5 levels lower||45%|
|6 levels lower||30% (no +XP/kill from gear)|
|7 levels lower||15% (no +XP/kill from gear)|
|8 levels lower||5% (no +XP/kill from gear)|
|9 levels lower||1% (no +XP/kill from gear)|
As this modifier is a simple multiplier, it doesn't need any extra limits to its working. Just multiply whatever experience you would normally gain by this percentage, you'll get that much extra.
As visible in the above table, you gain experience from killing monsters up to 9 levels lower than yourself and up to 3 levels higher than yourself. Normal experience gains per kill start to dominish heavily when you are 5-6 levels higher than your victims, and this bonus experience per kill from gear stops working on monsters 6 levels lower than you. For monsters less than 6 levels lower than yourself, you gain the full bonus from gear.
The four primary attributes in Diablo 3 are Strength, Intelligence, Dexterity, and Vitality. You cannot distribute points on these per level, they increase automatically each level. Each class as one attribute that is designated as their Primary Attribute, which increases damage done by a percentage. The multiplier is easy to calculate by turning your primary stat straight into percentage modifier. For example 123 Strength for a Barbarian would be a damage bonus of +123%. Overall damage dealt in this case would thus be Original damage × (1 + 1.23) = 2.23 × Original damage. The primary attributes per class are:
|Attribute||Starting Value||Increase per Level|
Strength is the primary attribute for Barbarians, increasing their damage by a percentage. In addition STR gives every class one point of armor per one point of Strength.
Intelligence is the primary attribute for Wizards and Witch Doctors, increasing their damage by a percentage. In addition INT gives every class 0.1 points of all resistances per one point of INT.
Dexterity is the primary attribute for Demon Hunters and Monks, increasing their damage by a percentage. In addition DEX gives every class some dodge. The dodge formula isn't as clear as the INT/STR ones. Refer to the Dodge section for more information about that.
Vitality gains will be the same for each class. Straight out of the box, Vitality only gives you more life. There are some skills that work with Vitality though, such as Barbarian passive Nerves of Steel, which increases the barbarian's armor by 100% of his Vitality.
When playing in party with other characters, monster power heightens to compensate for increased player power. Only monster HP is changed.
Before 11th June 2012 monster damage was also increased for multiplayer games. This was removed in a hotfix since it made DR requirement for melee characters in multiplayer games overly punishing. The increases were 5% per subsequent player on Nightmare, 10% in Hell and 15% on Inferno.