The mechanics thread - beta edition (in depth FAQ)
Much of the information here is obsolete as of version 0.9.3
Please post any information you discover that you think should be here. I'll try to keep it updated and organised. The information already here is the result of testing during the alpha, and observing the many patch notes.
Skills currently come in two main varieties: spells, and attack skills.
Attack skills use your weapon damage and so their effectiveness is dependent on your weapon, attack speed, etc.. Bonus damage from rings or other gear is applied when using an attack skill.
Current attack skills:
Spells do not draw their damage from your weapon in any way. They are affected by % cast speed, %fire/cold/lightning damage, %spell damage, and critical strikes. Integer damage bonuses on gear are not added to spells.
These spells never actually hit or do damage so they are unaffected by most modifiers and support gems. They are affected by cast speed, and skills with a duration are affected by %skill duration.
These skills are not affected by attack speed, cast speed, or anything else.
Support gems only affects skills where it makes sense. For instance, skills that do not already do damage (such as Temporal Chains) will not benefit from Added Cold Damage. Skills that do not already have an area of effect will not benefit from Increased Area of Effect, etc.
Here's a list of support gems currently in the game.
Individual Skill Notes
Only the fired arrow gets bonus damage from support gems / modifiers, not the poison cloud. Multiple poison Clouds do not stack.
The cloud lasts a set time, increased by the "Increased Skill Duration" passives. Enemies that enter the cloud are poisoned. The 'poisoned' effect will deal damage over time, increased by the Buff Duration passives.
Currently the poison on monsters has no graphical effect, this will be implemented soon.
Attack speed determines how fast Leap Slam activates, and how fast you fly through the air.
Shield Charge's damage is linked to the length of the charge. Charging the full length of the screen will do more damage than charging an enemy right next to you.
Only one of the three elemental damage bonuses is applied with each use of this skill (chosen randomly). It gives either bonus Fire, Lightning, or Cold damage, not all three at once.
Raise Zombie / Spectre
Most support gems that affect attacks (eg Added Lightning Damage) can be used with these skills to buff the attacks of the minions.
Support gems that affect projectiles (such as multiple projectiles, faster projectiles) appear to have no effect on the attacks of ranged enemies raised as Spectres.
Infernal Blow / Glacial Hammer
Glacial Hammer and Infernal Blow do the elemental conversion before any other modifiers (including on-weapon %Enhanced Physical Damage and quality!), using only base weapon damage.
This means that any physical damage mods and passive skills only apply to whatever physical damage is left after the conversion. The exact way the damage is calculated for these skills is unknown, for instance we don't know if the % melee damage passives from the strength tree affect the fire/cold damage portion.
Increased fire damage and cold damage mods/passives should work on the elemental portion.
Sweep has a 30% chance to knock back on hit. It's area of effect is a 300 degree arc (there is a 60 degree "blind spot" directly behind you).
Cleave's area of effect is a 180 degree arc.
When dual wielding, Cleave attacks with both weapons simultaneously, but suffers a damage penalty.
Dual Strike results in two separate, simultaneous attacks - one with each weapon. Each attack has it's own chance to hit, chance to critical, etc.
Skill gem experience gain
Each class gains a certain amount of life and mana per level, and also have some other bonuses.
In addition, each class gains different amounts of attributes from passive skills.
For example a Marauder taking a strength (red) passive gains 8 strength, 2 intelligence, and 2 dexterity. The same marauder taking an intelligence passive gains 2 strength, 4 intelligence, and 2 dexterity.
A Duelist will get 6/2/2 from strength or dex passives, and 4/2/2 from intelligence passives.
Life/mana per level
These are the amounts of life and mana gained by each class on level up.
Marauder: 8 life, 2 mana
Ranger: 4 life, 2 mana
Witch: 4 life, 4 mana
Duelist: 6 life, 2 mana
Templar: 6 life, 3 mana
Dex/Int: 4 life, 3 mana
Each class also has bonuses to certain types of armour. These are:
Marauder: +12% armour rating
Ranger: +12% evasion rating
Witch: +12% energy shield
Duelist: +12% armour rating, +12% evasion rating
Templar: +12% armour rating, +12% energy shield
Dex/Int: +12% evasion rating, +12% energy shield
Most gear has attribute requirements that must be met in order to equip the gear. These requirements come from the base item type and are unaffected by magical modifiers, quality, or number of sockets. A complete list of gear and attribute requirements can be found here
Some items have a level requirement that must be met in order to equip the item.
There are two factors that affect level requirements.
All weapons, armour, flasks and gems can randomly receive between +1% and +20% quality.
This value can be increased by Whetstones, Armour Shards, Flask Quality Upgrades, and Gem Quality Upgrades, but is capped at 20%.
The effect of quality depends on the item:
Modifiers are split up in to two main groups, prefixes and suffixes. A magic item can have only one prefix and one suffix, never two prefixes or two suffixes.
Rare items can have up to six modifiers, it is unknown if there is a limit on how many of these can be prefixes/suffixes.
A randomly generated rare item (from a drop or Orb of Alchemy) receives between four and six modifiers randomly, with the following odds:
1/12 chance of 6 mods
4/12 chance of 5 mods
7/12 chance of 4 mods
All modifiers have a level associated with them, and will only appear on items whos item level is greater than or equal to the modifier's level.
In general (but not always), percentage modifiers stack additively, and integer modifiers are applied before percentages.
Imagine I have 100 life, and two passive skills that increase total life by 15%. The total bonus will be 30%, resulting in 130 life.
Now imagine I am wearing boots that give +40 life, and have a passive skill that grants +20 life. The integer bonuses are applied first, giving me 160 life, then the percentage bonuses are applied to that subtotal, for a final total of 208 life.
One exception is the quality modifier on armour and flasks (but not weapons), which applies after all other modifiers. For example:
[there was an item linked here that has since been wiped. It had +69 armour, +9% armour, and +20% quality]
This Horned Casque has a base armour rating of 428. Then the +69 is added to get 497 armour. Then the 9% bonus raises it to 541, and finally +20% quality results in 650 armour.
Quality on weapons stacks additively with other % modifiers on the weapon.
Increased Item Rarity (IIR)
Increased Item Rarity % modifiers stack additively, and increase the chances of an item being magic, rare, or unique. For example with a total of +100% increased item rarity, For example, if you had +100% item rarity, you'd get twice as many magic items, twice as many rares and twice as many uniques.
This modifier has no effect on the number or type of currency items, scrolls, or gems that drop.
When in a party, only the modifier from the player who lands the killing blow on an enemy is counted.
If one of your minions gets a kill, the minion's IIR is added to yours and the total is used.
There are three types of sockets:
1. Strength (red)
2. Dexterity (green)
3. Intelligence (blue)
Sockets appear randomly on most equipable items. Higher level items can appear with more sockets than lower level items of the same type. For example, gear must have an item level of 8 or higher to receive two sockets.
The maximum amount of sockets that can appear on an item also varies by the type of item:
One exception to this is the starting weapon that appears on the beach at the start of the game. Its item level is 1 but it always has one socket of each colour.
This sword has 1 strength socket, 1 intelligence socket, and 2 dexterity sockets. Every socket is linked to every other socket. In this sword you could put:
So lets say you put in:
Cleave skill gem,
Raise Zombie skill gem, and
Added Cold Damage support gem.
You would get a cleave skill that does extra cold damage, and raise zombie skill with zombies that do extra cold damage.
You would not get zombies that have cleave, or raise a zombie every time you use cleave.
Additionally, two skill gems of the same type can be used in separate items to allow for more linking opportunities.
For example (thanks to tormenta):
In the above image,
When more than one gem of the same type is socketed at the same time, you always use the highest-level gem. So in the above example, if one of the Ice Nova gems was level one, and the other level six, your Ice Nova would have the stats of the level six version.
Similarly, if two of the same support gem are linked to the same skill, they do not stack. Only the highest-level gem gives a bonus.
Each item has a level associated with it that is equal to the monster level of the area it dropped in. You can check an item's level by picking it up on the cursor and typing /itemlevel in the chat box. This item level determines which modifiers it can receive, and how many sockets it can receive.
Vendor Item levels
Items obtained from vendors will have an item level equal to the character's level, but will not exceed the following maximums:
Normal Act 1: 15
Normal Act 2: 21
Cruel Act 1: 29
Cruel Act 2: 33
Ruthless Act 1: 41
Ruthless Act 2: 46
Merciless Act 1: ?
Merciless Act 2: ?
If you find a vendor that sells items outside of these level ranges, please post your finding.
Last edited by Malice on Nov 14, 2011, 12:04:53 AM
on Aug 15, 2011, 10:29:06 AM
Level plays a big role in many of the combat calculations in Path of Exile. Enemies higher level than you will be harder to hit, hit you more easily, do more damage, and take less damage than if you were the same level as them.
Similarly, enemies lower level than you will be easier to hit, have a harder time hitting you, take more damage, and deal less damage.
Level also affects the amount of XP you gain from killing enemies. Enemies higher or lower level than you will have their XP reward reduced. The exact formula for this is unknown. Enemies that are higher level than you, but only by 5 or less levels are not affected by this penalty. Enemies 6 or more levels above you will start to have their XP reward reduced.
Dual wielding grants a +25% attack speed bonus.
The default attack and certain other skills will alternate between each weapon, striking with each hand in turn.
Some skills (such as Cleave and Dual Strike) attack with both weapons at once, while others only use the main-hand weapon.
Hit & damage calculation order of effects
There are a number of steps involved in deciding whether an attack hits or not and how much damage is done:
* Evasion is checked first
* If the attack is not evaded, then blocking is checked
* If the attack is not blocked, then calculate damage reduction and resistances
* Subtract damage from energy shield/life
Accuracy is compared to enemy evasion when determining if an attack hits or misses. The complete formula is below:
chance to hit = ( attacker_accuracy / ( attacker_accuracy + defender_evasion ) ) * ( 2 * attacker_level / ( attacker_level + defender_level ) )
Chance to hit can never be lower than 5%, nor higher than 95%.
This was current as of 0.8.2, however it may have changed with the 0.8.3 update.
Evading an attack prevents all damage and other harmful effects from the attack. Only attacks and attack skills can be evaded. Spells cannot be evaded.
Blocking an attack prevents all damage and other harmful effects from the attack. Usually, only attacks and attack skills can be blocked, but there are some passive skills that allow you to block spells.
When an attack is blocked, the game first calculates if the attack would have caused a stun were it not blocked. If it would have caused a stun, the blocking animation is played. If it would not have caused a stun, then you get a "free" block with no animation.
It is unknown how this mechanic interacts with the new stun-resistant energy shield.
Armour / Damage Reduction
Damage Reduction reduces damage taken by a set percentage based on armour total, and the relative levels of attacker and defender. It applies only to physical damage.
As long as you have greater than 0 Energy Shield, you are immune to stun effects.
Energy Shield acts as an additional hit point pool on top of life. If you have any Energy Shield remaining when you take damage, the damage is subtracted from the Energy Shield first. Damage is only applied to life once all Energy Shield is depleted. The exception to this is Chaos Damage, which ignores Energy Shield.
Energy Shield will recharge if you do not take any damage for a certain period of time.
Whenever you use a skill or attack, you have a chance to deal a Critical Strike. Critical Strikes are rolled on a per-action basis, not per-monster.
So each time you use a skill, the Critical Strike roll is made once and only once. If you roll a Critical Strike, you will deal Critical damage to all enemies hit by the skill.
Critical Strikes do more damage than normal, based on your Critical Strike Damage Multiplier.
All characters have a base Critical Strike multiplier of 200%, meaning a critical strike does 200% of normal damage. This multiplier can be increased with various skills and modifiers on items.
For instance, with a multiplier of 250%, if you deal a Critical Strike with attack that normally does 100 damage, you will instead deal 250 damage.
The chance to deal a critical strike is based on your Critical Strike Rating, and the level of attacker and defender. You will have a greater chance of dealing a Critical Strike against monsters lower level than you, and a reduced chance to Critical against monsters higher level than you.
The exact formula for calculating Critical Strike Chance is unknown, but it can not be less than 5% nor more than 95%.
Critical Strike Rating, spells vs weapons
Critical Strike Rating and Critical Strike Damage Multiplier are calculated separately for spells and weapon attacks.
All weapons have a base Critical Strike rating listed on them. This only affects your chance to critical for attacks made with that weapon. It does not affect your chance to critical with a spell.
Statistics affecting Critical Strikes for attacks:
Statistics affecting Critical Strikes for spells:
There are currently 5 main types of damage, they are Physical, Fire, Cold, Lightning, and Chaos.
Fire, Cold, and Lightning are collectively known as Elemental Damage.
Damage reduction from armour and endurance charges only affects physical damage. Each of the elemental damage types has it's own resistance value (eg "Fire resistance") which is viewable in the character sheet. Resistances reduce damage taken, and are capped at 75%.
If you land a critical strike with an attack or spell that deals fire damage, the enemy begins Burning. Burning causes damage over time. Many monster types flee when burning.
Burning lasts 4 seconds, and the amount of damage over time is 1/3 of the fire damage dealt per second.
Hitting an enemy with cold damage can cause the enemy to be Chilled. Critical hits with cold damage can also cause the target to be Frozen. Chilled enemies move, attack, and cast slower, while frozen enemies cannot do anything.
If you land a critical strike with an attack or spell that deals lightning damage, the enemy becomes Shocked. This can be stacked up to five times on one target. In this state, monsters or players take 20% additional damage per instance of Shock.
Chaos damage ignores energy shield, reducing life directly.
Burning, Chilled, Frozen, and Shocked are collectively known as Status Ailments.
The duration of the chilled, frozen, and shocked statuses is related to the amount of cold/lightning damage dealt.
If the duration based on the damage would be less that 300ms, it's ignored entirely.
Some skills grant Endurance (strength), Frenzy (dexterity), or Power (intelligence) charges.
Each charge lasts a short duration before it disappears. Gaining a charge resets the duration of all accumulated charges.
Endurance charges are related to the strength attribute and grant +4% damage reduction, and +3% to all resistances per charge.
Frenzy charges are related to the dexterity attribute and grant +5% attack speed and +5% cast speed per charge.
Power charges are related to the intelligence attribute and grant +2% critical strike chance (not rating) per charge.
By default the maximum number of charges a player can have at one time depends on class. The pure classes can have up to five charges of their main attribute, and two charges of the other two attributes.
Hybrid classes can have up to four charges of each of their main attribute, and two of their off-attribute.
For example a Duelist can gain a maximum of four Endurance Charges, four Frenzy Charges, and two Power Charges. These maximums can be increased by certain passive skills.
The maximum party size is 6 players.
Effect on monsters
Monsters gain extra life for each additional player in the party. The exact amount is not known, and it is unknown what other buffs (if any) are applied.
Effect on loot
Each player in a party after the first gives the equivalent of +50% item quantity modifier on drops. So a party of three will see twice as many drops as a lone character.
Increased Item Rarity & Quantity modifiers are only counted from the player who lands the killing blow.
Effect on experience
Players in a party gain less experience for each monster kill than if they were alone. The amount of experience gained is currently proportional to character level+4. For example a level 10 and level 12 character are partied. The level 10 character gets 14/30 and the level 12 character gets 16/30 of the total experience. Only party members actually in the instance count toward getting XP. If one member is in town he gets no XP.
Monsters give +75% base XP for every party member after the first.
Effect on flasks
Only the character landing the killing blow on an enemy will gain flask charges. The same is true for all +life and +mana gained on enemy death modifiers.
Flasks have a +75% charge recovery bonus for each party member after the first.
Last edited by Malice on Sep 25, 2011, 8:13:14 PM
on Aug 15, 2011, 10:29:12 AM
Wraeclast area map
See this thread for an area map of Wraeclast.
All areas in Path of Exile are instanced. When you enter an area, a new instance is created. Once you leave the area, the instance will remain in it's current state for 15 minutes - if 15 minutes passes with no players entering the instance, it will be closed. Entering the same area again will create a new instance with a new randomly generated map.
Instances you create are private, and cannot be entered by other players unless they join your party. However, once a player has entered an instance, that instance remains associated with the player even if they leave the party. So it is possible to share an instance with non-party members in some circumstances.
Some areas have waypoints. Once activated (by clicking on the waypoint), waypoints allow you to travel instantly to any other waypoint you have activated.
Ctrl-clicking on a waypoint destination in the waypoint menu, or an area transition will bring up the instance management screen. This screen lists all available instances of the area you ctrl-clicked on, and the time remaining until they are closed. It also allows you to create new instances, and close existing ones.
Using the instance management screen you can have more than once instance of the same area open at one time, and choose which available instance you want to enter.
Last edited by Malice on Aug 24, 2011, 2:51:19 AM
on Aug 15, 2011, 10:29:18 AM
Last edited by Malice on Nov 3, 2011, 3:05:10 AM
on Aug 15, 2011, 10:29:24 AM
on Aug 15, 2011, 10:29:31 AM
Fixed some outdated info about level requirements
on Aug 15, 2011, 10:56:28 AM
Very nice Malice ! Thanks for the info, i'm sure lots of players will learn the game and understand it a lot better after reading your post. Someone should sticky it.
on Aug 15, 2011, 11:10:22 AM
I suppose someone should!
Thanks again for the great information!
Balance & Design
Last edited by Rory on Aug 15, 2011, 11:15:30 AM
on Aug 15, 2011, 11:14:35 AM
Grinding Gear Games
Added info on life/mana per level and class armour bonuses.
on Aug 15, 2011, 11:20:40 AM
Very nice Malice. I actually learned a couple things from this :)
Yes good sir, I enjoy slaying mythical creatures.
on Aug 15, 2011, 2:00:14 PM