There are certain skills that add bonuses or effects to the damage that they deal on an attack, some of those place certain indicators or "buffs" on the target (sometimes to deal damage per second or other timed effects), note that buffs are not always visible under the status bar
Blizzard imposed certain restrictions regarding the behaviour of these "Buff Placers"
probably for balance reasons
There are also other skills (which fall under the "Orb Effect" naming), which are based on abilities that were originally used on the "Orb" items in ladder Warcraft III. A restriction was also imposed on those skills because said effects were considered too powerful to be stacked (meaning bought in quantities to increase the effects), an "Orb Effect" skill may or may not be a buff placer.
Hence the two famous rules:
- Orb Effects do not stack (you will only get the effect of one "orb" skill)
- You can only place one buff per attack
Some effects aren't considered Orb Effects or Buff Placers, but are attack modifiers nevertheless, of which one good example is Cleave.
|Place||Place||Chain Lightning||Lifeleech||Place||Overrides on proc||Chain Lightning||Both||Both|
| Else Slot Priority||Latest||Entangle||Lifeleech|| Else Slot Priority||Overrides on proc||Entangle||Both||Both|
| Else Slot Priority||Latest||Incapacitating Bite||Lifeleech|| Else Slot Priority||Incapacitating Bite||Incapacitating Bite||Both||Both|
|Corruption||Chain Lightning||Latest||Lifeleech||Skadi|||| if Feedback was acquired later, else Both||Both||Both|
|Incinerate||Incinerate||Incinerate||Incinerate||Incinerate||Incinerate||Incinerate|| Else Both|| Else Both|
|Corruption||Overrides on proc||
|Corruption||Chain Lightning|| if Feedback was acquired later, else Both||Lifeleech||Skadi||||N/A||Both||Both|
|Orb||Buff Placer||(Ranged)||Critical Strike||Bash|
|Always||On Proc||Place||Place||Chain Lightning||Lifesteal||Chain Lightning overrides on proc||Chain Lightning overrides on proc||Chain Lightning||Critical Strike||Bash|
| Else Slot Priority|| Else Slot Priority||Only on the Bonus Shot||Lifesteal||||||Only on the Bonus Shot||Critical Strike||Bash|
|Always||Always||Corruption||Chain Lightning||Latest||Lifesteal|||| if Feedback was acquired later, else only OoV|| if Feedback was acquired later, else Both||Critical Strike||Bash|
|(Ranged)||Never||Always||Corruption||Chance skill overrides on proc||||Both||Frost Attack||Poison Attack||Both||Critical Strike||Bash|
|(Melee)||Always||Always||Place||Place||Frost Attack||Lifesteal||Frost Attack (Melee Skadi)||Frost Attack||Frost Attack||Critical Strike||Bash|
|Single Cast||Toggled||Never||Searing Arrows||Searing Arrows|| else ||Lifesteal||Both||Both||Searing Arrows||Searing Arrows||Searing Arrows|
|Auto Cast||Searing Arrows||Searing Arrows||Searing Arrows||Searing Arrows||Both||Both||Searing Arrows|| Else Item|| Else Both|
|Single Cast||Toggled or Cast||Toggled or Cast||Arrow Effect||Arrow Effect|| else ||Lifesteal||Arrow Effect||Arrow Effect||Arrow Effect||Arrow Effect|
|Auto Cast||Arrow Effect||Arrow Effect||Arrow Effect||Arrow Effect||Arrow Effect||Arrow Effect||Arrow Effect|||
|Never||Always||Corruption||Chain Lightning overrides on proc|| else ||Both||Poison Attack||Latest||||Critical Strike||Bash|
|Never||||Both||Both|| else Both||Both||Corrosive Breath|| else Both||||Both||Both|
|Special||Special||Corruption||Chain Lightning|| if Feedback was acquired later, else Both||Lifeleech||Both||||N/A||Both||Both|
|Critical Strike (On Main)||Bash (On Main)|
|Moon Glaives||No Attack||No Attack||Moon Glaives||Both||Moon Glaives||N/A||Moon Glaives||Both||Critical Strike||Bash|
|Split Shot/Flak Cannon||Corruption||Chain Lightning||If the item was acquired during the skill's duration: 
|Both||Both but Frost Attack only on main target||N/A||If the item was acquired during the skill's duration: Poison Attack.
|If the item was acquired during the skill's duration: Both.
|Corrosive Breath and Splash from Elder Dragon Form Lvl 2||Corrosive Breath, Splash||All||Corrosive Breath, Splash||All||All||All||Corrosive Breath, Splash||All||All||All|
|Frost Attack and Splash attack from EDF Lvl3||Splash||Chain Lightning overrides Frost on proc, Splash always works||Frost Attack, Splash||All||Frost Attack, Splash||Skill, Splash||Frost Attack, Splash||All||Critical Strike, Splash||Bash, Splash|
|||If the item was acquired (bought, picked up, received) before the first level of the ability only the ability will work.|
|||If Weaver auto-acquires his target it will slow while Geminate Attack is on cooldown, if he is ordered to attack it will slow on every hit except the one before the extra attack.|
|||Only Feedback will work if the target unit can be affected by Feedback (Maximum Mana > 0 and not magic immune), else the other ability works normally.|
|||Both if Feedback was acquired later, else Poison Attack.|
|||Both if Quelling Blade was acquired later, else Poison Attack.|
|||If you got the item before leveling the skill, then you will not Bash or Crit. If you acquire the item after leveling the skill, it will override on Proc, but will still consume Mana and show the projectile.|
|||Corrosive Breath is based on buff placer, but it will work even if the buff is not placed.|
|"Place"||Means: You will get the effect of the item in the highest priority slot. Order is (from highest to lowest): Top Left (1), Top Right (2), Mid Left (3), Mid Right (4), Bottom Left (5), Bottom Right (6)|
|"Slot Priority"||Item overrides if it's in the Top Left Priority slot, else skill works.|
The Maim from Sange, Sange & Yasha, and Heaven's Halberd used to be an orb effect, but this got changed in version 6.72.
Maim now fully stacks with every other attack modifier, with only two exceptions:
- Manually casting arrow effects (Searing Arrows, Frost Arrows, Poison Attack, Arcane Orb, Glaives of Wisdom, Burning Spears and Impetus) will never trigger a Maim.
- Multiple sources of Maim (Sange, Sange & Yasha, Heaven's Halberd) will not stack with each other.
Critical Strikes and Bashes
A Critical Strike is a ladder-based ability that gives the chance to deal a bonus percentage damage on a succesful attack of the weilding unit.
- Critical strikes are buff placers on the attack that trigger them, only for ranged units.
- Critical Strikes deal the same Attack type as the attacker but with Damage Type Normal (Physical, reduced by armor amount and type)
When two Critical Strikes proc at the same time only the last acquired will work, a skill is considered acquired when the first level is learned, and an item is considered acquired when it's picked up.
The red number shown by Critical Strike is displayed before reductions (this is why images don't show very low red numbers)
A Bash is also a ladder-based skill that gives a chance to deal a fixed amount of bonus damage and stun the target for any duration.
- Bashes are buff placers on the attack that trigger them, only for ranged units.
- Bonus damage from Bash on a ranged unit will be added to the unit's damage and not dealt separately, this is why you can Lifesteal off MKB.
- For ranged units Bashes deal Physical bonus damage (Reduced by armor type and amount) and magical stun (Blockable by Spell Immunity)
- For melee units Bashes deal Magical bonus damage (Reduced by spell resistance and blocked by spell immunity) and physical stun (not blockable by spell immunity), the damage is dealt separately.
- The stun duration of any bash will not override another stun duration that is longer (if try you stun someone that has 0.5 seconds of stun remaining with a 0.01 seconds stun yours will be ignored but the damage dealt)
When two bashes proc at the same time on a ranged hero only the last one acquired will work (stun and damage wise)
When two bashes proc at the same time on a melee hero they both deal damage and the longest stun duration is taken
It's important to know that both Bash and Critical Strike are basically the same skill using different settings, Critical Strikes with a factor lower than 1.0x will not interfere with other Critical Strikes, and all Bashes have a factor of 0x by default (using 0x as a damage factor will make you deal 1x damage without the red number) , creating the interaction explained above. The ability True Strike from MKB is a good example of this, It uses the setting "Never miss" which makes it disregard evasion, blind (from Laser, Whirling Axes, etc.) and others,and it uses a 0x damage factor so it has no stacking issues with other Critical Strikes. True Strike will follow the "Bash" setting on the main table.
Bash and Crit Stacking
- Melee Unit: A melee unit has no problem having a crit and a bash in the same attack (it might even have more than one bash, as explained earlier)
- Ranged Unit: When a Critical Strike triggers in a ranged unit it will override all the previously acquired bashes and crits, if a Bash that was acquired after all the crit procs then it deals it's bonus damage and stuns normally (In this regard new Basher will always be considered the last acquired ability)
- * Attack Speed
- * Cleave
- * Damage and Armor
- * Hitpoints and Manapoints
- * Invisibility
- * Lifesteal
- * Neutral Creeps
- * Targeting
- * Unit Statistics