Does multiple Damage Reduction Buffs stack?

[blufuERV]

Title.

I've been searching on the forum and reddit but couldn't find any info to understand if multiple spells of damage reduction stack, for example if i have Gift of Resilience active which offers 20% dmg reduction and use the spell Stone Shell that has up to 50% dmg reduction will it combine having like 70% dmg reduction?

[WindHunter]

There are, generally speaking, 2 types of effects: internal and external. This is true for both damage buffs and damage reductions.

An internal effect is one which a unit or building applies on itself or which is possesses passively. Two examples would be Moloch's Hardened Skin and Imperial's Defensive Stance. An external effect is one which is applied by an effect outside of the unit or building. Two examples would be Lifeweaving and Stone Shell. 

Internal effects stack infinitely with each other. So Wrathblades' Burnout damage buff stacks with Wrathblades S-counter damage buff. External effects stack with internal effects but not other external effects. Only the strongest external effect is chosen.

There are a few exceptions to this all. Ward of the North, Revenge, Lifestream, Ice Shields, and other such abilities are actually redirect abilities. These stack with 1 non-redirect external effect and all internal effects. Redirect effects do not stack with each other. Another exception is Unholy Power, which, to my knowledge, stacks with everything. 

[blufuERV]

On 5/22/2023 at 3:17 AM, WindHunter said:

There are, generally speaking, 2 types of effects: internal and external. This is true for both damage buffs and damage reductions.

An internal effect is one which a unit or building applies on itself or which is possesses passively. Two examples would be Moloch's Hardened Skin and Imperial's Defensive Stance. An external effect is one which is applied by an effect outside of the unit or building. Two examples would be Lifeweaving and Stone Shell. 

Internal effects stack infinitely with each other. So Wrathblades' Burnout damage buff stacks with Wrathblades S-counter damage buff. External effects stack with internal effects but not other external effects. Only the strongest external effect is chosen.

There are a few exceptions to this all. Ward of the North, Revenge, Lifestream, Ice Shields, and other such abilities are actually redirect abilities. These stack with 1 non-redirect external effect and all internal effects. Redirect effects do not stack with each other. Another exception is Unholy Power, which, to my knowledge, stacks with everything. 

Thank you for explanation. Now I can build accordingly.