Unique Attack Modifier

Orb Effects in Dota 2 refer to attack modifiers that alter your heroes basic attack to provide an additional effect. An example of this is Helm of the Dominator, which gives your hero lifesteal. For balance and legacy reasons, Orb Effects, with very rare exceptions, do not stack. Having more than one at any time is generally considered useless. Certain hero abilities, such as Broodmother's Incapacitating Bite, also count as orb effects. Not all attack modifiers count as orbs. All items in the Artifacts shop, with the notable exception of Yasha, grant either Orb Effects or Buff Placers.

When two Orb Effects are acquired by one Hero, only one of the effects will take priority per attack. If the Hero has any Orb Effects that do not always proc, such as if they have a Cooldown, like Weaver's Geminate Attack, or they have a chance to occur, such as Maelstrom, they take priority if their conditions are met. If the Hero has any abilities that count as Orb Effects, either manually cast or passive, they come next in priority. For any other Orbs, only the first one obtained will be applied.

Items that grant Orb Effects










List of hero skills that grant Orb Effects












* These Orbs can be activated manually or placed on Autocast to cast. Casting these Orbs requires Mana. Manually used Orb abilities can be used to Orb Walk.

Buff Placers
Buff Placers follow the same rules as Orb Effects, but count separately. Buff Placers usually apply a "buff" (actually a debuff) to the target, and can be carried either alone or by an Orb Effect. For example, Eye of Skadi applies a debuff to the target that slows its movement speed by 30% and attack speed by 20%.

Buff Placers that are not Orb Effects can be used in conjunction with Orb Effects. Buff Placers will also stack with other Buff Placers, meaning that Eye of Skadi's slow can stack with Desolator's Corruption effect. However, Desolator is also an Orb Effect and will not stack with Diffusal Blade, which is also an Orb Effect.

List of Buff Placers

 * [[Image:Poison_Sting_icon.png|Poison Sting|40px|link=Venomancer#Poison_Sting]] Venomancer's Poison Sting
 * [[Image:Skadi.png‎|Eye of Skadi|40px|link=Eye of Skadi]] Eye of Skadi

Critical Strike and Bash
Critical Strike also counts as a Buff Placer for ranged heroes, on the attack in which it procs. Crystalys and Daedalus both grant Critical Strike. Monkey King Bar's True Strike ability also counts as a Critical Strike, but will not interfere with other Critical Strikes.

Bash likewise counts as a Buff Placer for ranged heroes on attacks in which it procs. Bash may be gained from Skull Basher.

Stacking
In Dota 2 Orb Effects generally do not stack, with one orb effect always taking priority. There are several exceptions to this, however. Mjollnir and Maelstrom currently will work with other orbs, overriding them whenever the chain lightning occurs. Lifesteal will work with both ranged and melee Eye of Skadi.

Otherwise, all hero skills will override any orb effects obtained from items. For other orb effects, the first acquired will take priority.

Note that activatable Orb Effect skills only count as orb effects when cast, either from autocast or manually, and so can theoretically be used part of the time, with another orb effect active the rest. In practice this is rarely useful.