Whenever you hear this, what it means is that a certain effect has an increased percentage, but not directly increased. If you have 20% of something, and an item or skill that gives another 20% of that something, if it stacks diminishingly, it will not equal 40%!
The way to work out diminishing returns is to use this formula:
T = C/100 + (100-C)/100 * E/100
T is the Total percent, C is the Current percent, and E is the Extra percent.
For example, if you have a melee hero with 25% bash and buy the item Cranium Basher, the extra 15% bash stacks diminishingly. To work out the total percent, use the formula:
T = 0.25 + (100-25)/100 * 0.15
= 0.25 + 0.75 * 0.15
= 0.25 + 0.1125
= 0.3625
The total bash percent would be 36.25%. If you added another Cranium Basher, to work out the bash percentage, again apply the formula. Note that the Current Percent is changed to 36.25%
T = 0.3625 + (100-36.25)/100 * 0.15
= 0.3625 + 0.6375 * 0.15
= 0.3625 + 0.095625
= 0.458125
The total bash percent would then be 45.8125%.
--------------Critical------------------
1St of all, multiple Burizas on a hero will cause the critical strike chance to stack diminishingly. To calculate the chance to critical strike, for a hero with two burizas, we use the Diminishing Return formula:
T = 0.20 + (100-20)/100 * 0.20
= 0.20 + 0.80 * 0.20
= 0.36
With two burizas, a hero has a 36% chance to Critical Strike.
A hero with Critical Strike as a skill who gets Buriza will be Critical Striking a lot, but it is important to note that when the infamous "double critical" occurs (when you see two criticals appear at one time, on your screen), they do not stack. The hero's skill will take precedence over the item's effect, which can be a good thing sometimes, or a bad thing others.When a hero has a Crystalys and Buriza, again, when the infamous double critical occurs, it doesnt really happen - the criticals do not stack! In this case, the Crystalys's critical strike will take precedence over the Buriza's critical strike, so you will actually deal less damage than you would have, had you just got a Buriza
alone
-----------------Bash-----------------
There are two other passive skills which can stun for a short duration. The first is Sniper's Headshot, which has a 40% chance to stun for 0.1 seconds. The second is MKB, which has a 30% chance to stun for 0.1 seconds. It is important to note that these skills will not stack with each other; for example, if you bash a target with the bash from a cranium basher, and then the short bash from the MKB occurs, the stun from the basher will be cancelled.
For easy reference:
On heroes without bash -
1 Cranium Basher : 15% bash
2 Cranium Bashers : 27.75% bash
3 Cranium Bashers : 38.5875% bash
4 Cranium Bashers : 47.79937% bash
5 Cranium Bashers : 55.62946% bash
6 Cranium Bashers : 62.28504% bash
On heroes with 25% bash (Timestopper, Slithereen Guard) -
1 Cranium Basher : 36.25% bash
2 Cranium Bashers : 45.8125% bash
3 Cranium Bashers : 53.94062% bash
4 Cranium Bashers : 60.84953% bash
5 Cranium Bashers : 66.7221% bash
6 Cranium Bashers : 71.71378% bash
On heroes with 10% bash (Troll Warlord) -
1 Cranium Basher : 23.5% bash
2 Cranium Bashers : 34.975% bash
3 Cranium Bashers : 44.72875% bash
4 Cranium Bashers : 53.01944% bash
5 Cranium Bashers : 60.06652% bash
6 Cranium Bashers : 66.05654% bash
-------------Magic Resistance--------------
Every hero starts out with a natural 25% magic resistance to spells. A spell that says it does 300 damage will only do 225 damage to heroes (75% of 300). On top of that, there are items which give magic resistance, and even some heroes that have skills which increase magic resistance. Getting extra magic resistance stacks diminishingly, though.
When a hero buys a Planeswalker's cloak, which gives 15% magic resistance, to calculate the total magic resistance we use the formula for Diminishing Return.
T = 0.25 + (100-25)/100 * 0.15
= 0.25 + 0.75 * 0.15
= 0.25 + 0.1125
= 0.3625
Total magic resistance with a Planeswalker's Cloak is 36.25%.
When a hero upgrades the Planeswalker's cloak to an Aegis of the Immortal, which gives 35% magic resistance, to calculate the total magic resistance we again use the formula:
T = 0.25 + (100-25)/100 * 0.35
= 0.25 + 0.75 * 0.35
= 0.25 + 0.2625
= 0.5125
Total magic resistance with an Aegis of the Immortal is 51.25%. Note that the current magic resistance was 25% because you no longer have the Planeswalker's cloak! If the hero with an Aegis then buys another Planeswalker's cloak, the magic resistance will not stack. Likewise, if the hero with an Aegis then buys another Aegis, the magic resistance will, again, not stack.
-------------------EVASION---------------
There are two ways to get evasion: Through a hero that has a skill that gives evasion (Phantom Assassin's Blur, Panda's Drunken Brawler or Bounty Hunter's Jinada). The other way is to get either the item Butterfly, or the item Radiance ("blinding" effect counts as evasion; ta to Lionel for that).
Evasion never stacks. Period. Getting multiple butterflys, or a butterfly on a hero that already has evasion does not do anything (although on a hero that already has evasion, the hero's skill will take precedence).Note: Evasion is different from a skill that will cause a target or targets to miss. Evasion stacks with spells that make a target/targets miss! Evasion of a hero and accuracy loss of an opponent do stack together, diminishingly... For example, a Troll Warlord with a butterfly would have 25% evasion on top of making an enemy miss 42% of the time. His theoretical evasion would be:
TE = 42 + (100-42)/100 * 25
= 56.5%
Note that Backtrack (Voidwalker) is different from evasion. A butterfly on Voidwalker will stack with his backtrack. The way it works is, first, the Voidwalker will have a chance to evade the attack (25%). After this, if the evasion doesn't proc, he will then have a chance to backtrack the hit (25%). So, total evasion would be:
TE = 25 + (100-25)/100 * 25
= 43.75%