General Mechanics Guide
WDM MECHANICS
WDM stands for Weapon Damage Multiplier. Put simply this is a % modifier of damage done. If you would do 1,000 damage, and your skill has 50% WDM, then you do 500 Damage before further reductions.
► Calculating Weapon Damage
Modifiers for weapon damage are applied as follows:
1: Ethereal Bonus (50% base damage on weapon)
2: %Enhanced Damage (%ED)
3: +Flat Damage.
4: %Physical Damage, this includes %EWD from items, %damage from skills / passives and buffs and str/dex factor, which are all ADDED up into one big multiplier (%dmg = %EWD + %physdmg + %dex/strbonus)
5: Deadly Strike (if it rolls successfully, x2 all damage up until this point)
6: %Conversion is applied.
7: +Flat elemental damage from weapon/gear/skills.
8: %WDM of skill used.
Leech
Life and Mana Leech get reduced a higher amount in higher difficulties, and then again vs bosses in each difficulty.
Normal Effecitiveness : 1/4 th.
Nightmare Effectiveness : 1/7th.
Hell Effectiveness : 1/15th.
Bosses have a 40% reduction to leech in all difficulties.
Crushing Blow
Reduces an enemies current HP by %.
1/4 vs enemies while attacking them in melee, 1/8th with ranged
In Sigma Bosses are completely immune to crushing blow.
Deadly Strike
Flat % chance of doubling physical damage on the attack on success, this is calculated before conversion.
Conversion
A WDM skill can carry conversion. This takes a stated % of your damage you would deal, and then shifts it to whichever element is stated. This is not amplified by spell damage, but it does take pierce into account.
Reducing Incoming WDM damage
DEFENSE: Most WDM attacks first have to pass the defense check, it uses the following formula:
Chance to be Hit = 100 * AR / (AR + Defense ) * 2 * attacker lvl / (attacker lvl + defender lvl)
Attacker and defender can be both a player and a monster, there’s no difference.
If it rolls successfully, then the attack will proceed to check for Block.
If the attack doesn’t pass the defense check, the defender doesn’t trigger any recovery animation
BLOCK: ALL WDM attacks have to pass the Block Check, it simply uses your block chance to attempt to block the incoming attack. If the attack gets blocked, it will trigger the Block Recovery Animation.
NOTE: Some monsters also have block, and in the case of bosses, their Block Recovery will be 0 frames, so it essentially functions as a wdm specific avoid.
*insert block formula here*
AVOID: ALL attacks (wdm or not) have to pass the Avoid Check, its essentially the same as block except it doesn’t trigger an animation if it rolls successfully.
Procs
Procs Have different “bases” and “triggers”. A proc cannot scale with any kind of + skill. Procs of the same exact base but different levels roll independently of one another. If a proc is the same exact proc, down to the lvl of the proc, they become additive and only roll their chance once. (1% chance to proc lvl 1 knife, 1% chance to proc lvl 2 knife, 1% chance to proc lvl 3 knife, vs (1+1+1)% chance to cast lvl 1 knife).
WDM based procs: All arrow/javelin/knife procs scale distance with level, but do 50% wdm. These leech just as a regular attack would. They carry CB, DS and anything else a normal ranged attack would
Spell based procs: These scale with spell damage and pierce.
On Attack / On Striking
On attack procs are just about any melee attack. Only a melee “slap” can proc these. Note some skills (thorn strike for example) can be cast at range, so they fall under “On striking”.
On striking procs are any %WDM trigger at all. A javelin proc can proc another javelin proc, etc.
On Kill / On Deathblow
On kill refers to killing an enemy with WDM damage or with a specific set of rules with poison damage (see poison mechanics).
On deathblow (previously “when slain”) refers to killing an enemy with any source of damage including spell damage and poison ticks. Just like wdm procs, on slain procs can chain each other.
SPELL MECHANICS
Pierce
Enemies can be brought down to -100% resistances. This amount changes depending on if the enemy is a regular mob or a boss, and what difficulty you are currently in.
Enemy res in Normal starts at 0 and doesn’t increase even for bosses.
Enemy res in Nightmare is 0 for phys/mag, 15% elemental and poison.res
Enemy res in Hell is 0 phys/mag, 35% elemental and poison, and includes a 10% chance of an addition 15% phys res (changes in sigma?)
Bosses in destruction have 35% phys/mag res, 70% elemental and poison res.
So to bring a boss to -100% res in destruction you would need 170 pierce.
Samael, Herald of the end, has 199% Elemental res, 50% physical and magical resistance, is immune to poison and is pretty much the only exception to these rules.
Immunities
Immunities are changing in sigma. If an enemy “absorbs” an elemental type they are 30/50/75% resistant to that type. This cannot be reduced in any way shape or form.
► Pierce Calculations
Pierce effect:
Vs mobs (35% res):
No pierce = 65% dmg dealt,
65 pierce = 130% dmg dealt (x2 base dmg)
135 pierce = 200% dmg dealt. (x3 base dmg, x1,5 dmg gain)
Vs bosses (70% res):
No pierce = 30% dmg dealt.
30 pierce = 60% dmg dealt (x2 total dmg)
90 pierce = 120% dmg dealt (x4 total dmg, 2x total dmg gain)
170 pierce = 200% dmg dealt (x6,67 base dmg, x1,67 total dmg gain)
► Spell Damage Calculations
Spell damage effect
100% spell dmg = x2 base dmg.
200% spell dmg = x3 base dmg (x1,5 total dmg gain)
300% spell dmg = 4x base dmg (x1,33 total dmg gain)
400% spell dmg = 5x base dmg (x1,25 total dmg gain)
And so on.
In short, there's diminishing returns the more %spell damage you stack
Energy Factor:
In Median XL, direct damage spells gain a damage bonus from energy. This bonus has diminishing returns: the damage gained per additional point of energy is lower if you already have lots of energy to begin with.
The energy factor bonus on some caster items modifies this curve, causing each point into energy to provide a significant benefit until much higher levels of energy. Energy factor is particularly effective for high level characters with most or all points into energy.
The formula is as follows:
(260∗(energy+10)/250+energy) + min((energy∗energyfactor)/15000,200) = % increased spell damage
Note : Strength Factor could be thought of as Energy Factor just based on another stat. It is additive with Energy Factor and they use the same formula for added damage.
POISON MECHANICS
Poison can proc ‘’on kill’’ effects normally, EXCEPT if the first frame of the poison kills the target, this is only doable if you’re ridiculously overpowered for the area (ex: endgame fully geared char in normal cold plains)
Basic: poison damage is listed as the total damage over x seconds. This value however, does not take in account how fast you are actually dealing damage. To calculate that, simply divide the total damage displayed by the length of the poison (ex: our lorenado deals 1000 damage over 10 sec will be displayed as 1k in character sheet, but you’re actually dealing 100 damage per second).
%poison skill duration will increase the length of the poison while keeping the damage per second value, so if in our previous case we add 100% poison length increase, damage will ‘’increase’’ to 2000 over 20 sec (still 100 damage per second).
%poison skill damage on poison spells will increase both the total damage and the damage per second (1000 over 10 becomes 2000 over 10 under 100% poison spell damage, dps increased from 100 to 200)
-% enemy poison resistance will increase both poison length and damage per second ONLY ON MONSTERS, this is because monster’s poison resistance both lowers damage per second and poison length by the displayed amount. If with our lorenado we hit a 75% poison resist monster, we won't be dealing 250 damage over 10 seconds, we will be dealing 63 poison damage over 2,5 seconds, both cases are 25 damage per sec. This makes poison pierce especially important, because it doesn’t only improve damage per second, but also total damage.
All these stats are multiplicative with each other. (1000 over 10 with 100% spell dmg, 100% duration and -100 enemy resist becomes 16000 over 40 seconds, 400 damage per second)
Some enemies, most notably select bosses will have additional %poison length reduction, on top of their poison resist. This reduction cannot be influenced in any way and cuts length by the specified amount.
On player characters, poison length reduction is a separate stat (that is also reduced by -50% and -100% in nightmare and hell) and poison resistance only lowers damage per second but not duration.
Multiple poison sources do not stack, the highest damage per second instance will overwrite the other. This means that a 1 second poison can and will overwrite a 40 second poison if its damage per second is higher, even if total damage dealt is less. On the other hand, repeatedly attacking a target with poison will guarantee that the highest damage per second possible will be applied in case of varying dps.
► Poison Technical Stuff
While damage is displayed in points and length in seconds, both are calculated and applied using more precise units of measurement: each point is divided into 1/256ths, while each second is divided into 25 frames.
Poison damage is displayed as the total damage applied over its length, but it's calculated by applying its 1/256 damage rate for a specified number of frames: 100 damage over 5 seconds applies poison damage at a rate of 205/256 for 125 frames, which is displayed as 100 Poison Damage Over 5 Seconds (125 * 205/256 over 125/25).
This is the explanation of why poison length and damage aren’t subjected to rounding issues.
When multiple items applying poison damage are equipped, then the rates are added and the lengths are averaged. Skills that add poison damage to %wdm attacks are considered different items. Sockets are also different items even if all stacked on the same item.
SLOW MECHANICS
► Indepth Slow information
=Types of Slow=
1.) SLOWS TARGET
Slows ANY enemy YOU HIT and ANY enemy slowed through WDM skills (WDM - explained later in FAQ).
2.) SLOWS MELEE TARGET
Slows enemies that YOU HIT with MELEE weapon only (in this case, WDM skills don't carry slow effect on other enemies).
3.) SLOWS ATTACKER
Slows any MELEE enemy that HITS YOU (ranged enemies are not slowed).
4.) SLOWS RANGED ATTACKER
Slows an enemy that HITS YOU with MISSILE ATTACKS (THROWS) or simply said: ANY enemy that hits you by NOT swinging a MELEE weapon at you.
5.) Cold Slow (Chill)
Chill is 20% slow, as long as the effect lasts.
6.) Skill based Slow
Skills (either oSkills or skills in character's skill tree) that in some way effects the attack speed of enemies, a.k.a, slows them down: Chronofield, Miasma, Shower of Rocks, Snake Stance, Spellbind, Talon's Hold...
7.) Summoned minion Slow
Lamia's "Slows Target" ability that slows enemies on striking (by percentage).
Void Archon's Warp Field aura that "reduces enemy attack speed".
=Slow Cap=
1.) The cap for slow against non-boss monsters is: 90% for one source of slow (Example: 90% slow from items) and 95% for more sources of slow (Example: 60% slow from Chronofield and 35% from items)
2.) The cap for slow against bosses and players is 25% in all cases.
=Slow Overriding=
1.) "Slows (Melee) Target" and "Slows (Ranged) Attacker" override each other!
Example 1: If you have 50% "Slow Target" and 25% "Slows Attacker", they don't add up (stack). What happens is: when you attack an enemy you slow him down by 50%, but when an enemy hits you, he actually speeds himself up (at the moment of attack, enemy is slowed only by 25%, because he counts as an attacker and not as a target). If the values were reversed, the enemy would be slowed by 50%.
2.) "Slow Target" overrides "Slows Melee Target"!
Example: If you have 30% "Slow Target" and 60% "Slows Melee Target", at the moment of attack, an enemy WON'T be slowed by 90% (because these modifiers DON'T STACK), but only 30%. "Slow Target" will ALWAYS override "Slows Melee Target".
[6:53 PM] Gavin_K88: ==Other Facts==
1.) Different sources of slow means slow is applied via different "states". What's a state? It doesn't necessarily have to be visible, but in most cases it is. For example: every morph in the game is a different state, every curse that looks differently is a different state, every buff/debuff is a state. Some of those states stack (like buffs) and some don't (like curses/morphs). So, what are other "slow sources"? Basically anything that will slow an enemy (for example: Chronofield, Spellbind, etc.), but doesn't use the same state/animation as the slow we get from items.
CONCLUSION: Slow is capped at 90% for ONE source (example: slow from items), but 95% for MORE sources (example: slow from items + slow from some skill).
2.) Duration of slow effect from items is 30 seconds.
3.) ONLY WDM skills (Weapon Damage Modifier) carry slow to other enemies! WDM skills are easily recognized by their description.
Example: "1/2 Weapon damage" ; "3/4 Weapon Damage" ; "3/2 Weapon Damage"
4.) Slow from items ADD UP (STACK) with any skill based slow.
Example: 30% slow target (from items) + 50% slow from Chronofield (skill) = 80% slow in total.
5.) Slow from items ("Slow Target", "Slows Melee Target", "Slows Attacker", "Slows Ranged Attacker") trigger "On Striking".
MISC MECHANICS
Magic Find
Magic find only influences the “rarity” roll of an item and is one of the last rolls to happen on a drop. Therefore increased magic find only changes the number of magical/rare/set/uniques you get and has no effect on the tier of base type of the item. The item base type is first decided, then tier, then it’s rarity is rolled, if a set/unique item is rolled and there are multiple drops for that set/unique, the specific item is then decided by a roll between these available items. (Will double check this for accuracy later). Magic find does not affect shrine, rune, or quantity of item drops.
If an item rolls unique but there is no possible unique for it, it drops as a set, if an item rolls set but there is no set possible for it, it drops as a rare.
XP gain:
This stat simply increases the amount of exp you gain by a %, 100% = 2x exp gain. This is MULTIPLICATIVE with player number exp boost ( so p2 with 100% exp is 3x exp not 2.5x exp)
No Drop
This is the thing that fucks you raw and doesn’t call the next day. Decreases with every player in your game that is partied. No drop is basically a chance for the game to roll to eat your drop. It is the devil. That is all you need to know mechanically here.
Orange Text Procs:
Amazing Grace: 5% on attack proc, turns you invulnerable (100% avoid) for 1,6 seconds.
Thunderfury: 50% on attack proc, emits charged bolts that deal 75% WDM damage with 100% lightning conversion.
Area of Effect Attack.100% on attack proc, emits a physical wdm nova (100% wdm) that hits all enemies within 5 yards from the target. Multiple novas do NOT stack, each nova hits every enemy ONCE and it can proc on striking, leech, etc.
USEFUL LINKS:
http://www.mannm.org/d2library/faqtoids ... s_eng.html - Mix of useful and technical stuff, fairly in depth
http://www.theamazonbasin.com/wiki/inde ... =Diablo_II - Mix of useful and technical stuff, fairly in depth
https://diablo2.diablowiki.net/Item_Generation_Tutorial - Technical and very in depth explanation of item generation
TO BE ADDED
Merc Mechanics