[Tips]Mathcrafting and WC3 Mechanics Guide

[ntinaras30]

Missunderstanding dota mechanics is quite common even among skilled players and often leads to ineffective item/skill builds. The following guide is here to tell you how warcraft and dota works.

 

1. Basic attribute info

Apart from +1 damage for a each point in chars primary attribute, stats give following:

 

1 Strength:

+ 19 max HP

+ 0.03 hp regen/second

 

1 Agility:

+ 1% IAS

+ 1/7 Armor

 

1 Inteligence:

+ 13 max Mana

+ 0.042 mana regen/second

 

2. Regeneration

- HP regeneration per second is based on following formula:

  [regen] = 0.25+(str*0.03)+[regeneration from skills/items]

- Mana regeneration per second is based on following formula:

  [mregen] = int*0.042*(1+[regeneration from skills/items])

- Items that directly increase hp an mana (like boosters) do not increase regeneration rates in any way.

 

3. Evasion

Evasion is a chance of not being hit while attacked. Evasion in warcraft3 do not add up or stack in any way(items/skills). Only highest bonus counts. Period. Plz dont make butterfly on PA ;]. The only exception to that is Faceless Void's Backtrack ability. In his case chance of avoiding hit damage is calculated as follows (basically both backtrack and evasion can proccs are independant):

 

[Evade chance] = 1-(1-[backtrack%])*(1-[evasion%])

 

example: evasion from butterfly (25%) and highest level backtrack (25%) gives:

[Evade chance] = 1-(0.75*0.75)= 43.75% chance to evade

 

4. IAS and attack speed

Attack speed (or HPS-Hits per second) is a result of 2 factors:

- base attack time (BAT) which defines how much time (in seconds) would one attack take without taking into account any bonuses. BAT for most charecters is 1.70s, but for some (like magina and terrorblade, let me know if there are any others) its 1.45s

- increased attack speed (IAS) which is calculated as follows:

  [iAS] = [agility]*1% + [sum of all IAS from items and skills]

 

The HPS formula is as follows:

 

[HPS] = (1+[iAS])/[bAT]

 

example: Magnus with 55 agility wearing power treads (+30% IAS) and Hyperstone (+55% IAS) will attack:

[HPS] = (1+(0.55+0.3+0.55))/1.7 = 1.41 times per second

 

Based on the above its clear that agilty heroes don not benefit as much from power treads as str or int heroes do, because their agility is already high, and the bigger IAS you already have, the smaller the gain from additional IAS is.

 

5. Bashing

- Every bash effect has is proccing independantly from others

- In case 2 or more bash effects would trigger upon hit, the bash with the slowest stun duration takes place (meaning for example that Faceless Void stun will override basher stun if both procc at the same time, so you will get +damage from skill).

- Items that can bash are:

  basher - 10% stun chance on ranged hero and 15% stun chance on melee hero. stuns for 1.1 secs

  MKB - 30% stun chance. Stuns for 0.01 secs. Deals additional 90 damage.

  So if you are going for permbash build, dont make mkb, because it will override some of your normal stuns with its wimpy 0.01 sec stun.

- If stunned target gets hit by another bash effect, the new stun overrides old one (so again mkb will just interrupt permbashing)

- Total bashing chance from multiple items/skills is calculated as follows:

[bash%] = 1 - (1-[effect1%])*(1-[effect2%)*(1-[effect3%])*...

 

example: Faceless Void with level 4 time lock (25% chance for 1 sec stun and additional damage), 2 bashers and mkb attacks enemy target. His chances of getting any stun effect on enemy target on hit are:

[bash%] = 1-0.75*0.85*0.85*0.7 = 62.07%

However, chances for each effect are as follows:

mkb stun = 30%

time lock stun = (0.7*0.25) = 17.5%

basher stun = 0.525*(1-0.85*0.85) = 14.57%

nothing happens = 37.93%

 

6. Criticals

- Same as bash effects, each critical effect is proccing independantly from others

- In case 2 or more critical effects would trigger upon hit, the critical with lowest multiplier takes place

- The average expected damage multiplier for several critical effects is calculated as follows (we assume that first effect has lowest multiplier and last effect has the highest multiplier:

[mul] = 1+ [critical chance 1]*[critical multiply 1] + (1-[critical chance 1])*[critical chance 2]*[critical multiply 2] + ...

- based on above burize will be more effective on char that has no other critical than on PA or skelly

 

7. Cleave

- Cleave/Splash effects simply add up :

  [Cleave % total] = [cleave % 1] + [cleave % 2] + ...

- there is no cap to cleave - if you have 150% you will be hitting secondary targets harder than you hit main target.

 

8. Armor

- each positive armor point acts like 6% of additional hp against normal attacks. therefore having 20 armor on 1000hp hero will effectively make him 2200hp against normal damage

- for negative armor, target is dealt increased damage based on following formula:

  [damage multiplier] = 2-0.94^(-armor)

- based on above each armor point increase gives less and less compared to previous increase

 

9. Orbs, Auras and Effect Stacking

The following table displays how various orb effects work with each other:

*special - orb on item in the higher inventory slot will work

 

- auras stack with everything including orb effects, so for example:

  - lifeleech aura on skelly will stack with helm of dominator will giving total of 40% lifeleech

  - nevermore aura will stack with desolator and slardar ulti for a huge armor breakdown

- multiple auras work with each other unless they are based on the same aura effect like basiluss aura and sven's toughness aura in which case higher bonus will apply.

 

10. Magic resistance

- Magic resistance applies to magic damage only (pudge hook is not magic damage skill for example)

- Every hero has basic magic resistance equal to 25%, meaning if 100 damage is dealt by a spell you only take 75 damage

- magic resistance adds up in following manner:

[total MR] = 1 - (1-[natural MR])*(1-[item MR])*(1-[skill MR])

only one item with highest resistance percentage is taken into above formula - multiple aegis/cloak do not stack in any way

- based on above, antimage with 40% mr from skill wearing 20% Aegis will have:

mr = 1 - 0.75*0.60*0.80= 64% magic resistance

 

credits: Private_Dream