Additive or Multiplicative ? Incoming Damage ? Wondering about skills and traits.

Hello, I'm sorry if it has been answered before, but it seems there is still no consensus about it. How do those -% damage works ? Do they add up or they just do a multiplication ? What is the difference between an -% Incoming Condi/Damage and a Condi/Damage -% Reduction ?

Aren't they all the same thing ? For Damage, isn't it the same thing ? What about Condition Damage ?

If I do Breakrazor's Bastion + Versed in Stone, do I get 100% Condition Damage reduced or do I get Condition Damage Reduced 50% AND -50% Incoming Condition Damage ?

If I have Protection (33), Rite of the Great Dwarf (50) and Vengeful Hammers (20), do I reach 100% Damage reduction ?

And all others situations you can think of. What is it really ?

Revenant :

Rite of the Great Dwarf (5s): Gain 50% damage reduction. You are still susceptible to conditions and control effects.Traited -> Versed in Stone : Condition Damage Reduced: 50%Vengeful Hammers : -20% Incoming Damage, -20% Incoming Condition Damage

Renegade :

Breakrazor's Bastion (10s): -50% Incoming Condition DamageAll for One (Trait) : Using Legendary Renegade abilities grants protection to allies near the summoned warband member. (Protection (4s): -33% Incoming Damage)Righteous Rebel (Trait) : Condition Damage Reduced: 33%

% modifiers in GW2 are all multiplicative. This means:

• Having 5 +10% dmg buffs -> 1.1 1.1 1.1 1.1 1.1 = 1.61 resulting in a 61% dmg buff
• Having 5 -10% dmg reductions -> 0.9 0.9 0.9 0.9 0.9 = 0.59 resulting in a 41% dmg reduction

Using your example of Protection, RotGD and VH you get 0.67 0.5 0.8 = 0.27 which is a 73% dmg reduction. You cannot reach 100% dmg reduction.

As far as I know there is no difference between an -% Incoming Condi/Damage and a Condi/Damage -% Reduction. It's just different wording for the same thing. For conditions the game only differs between damage and duration.

Thank you BunjiKugashira, it clears a lot ! I was toying around Renegade and was looking a way to manage conditions better in PvP Scourge/Mirage Condi Meta. Kinda a little let down when you need to invest in traits and use more than 1-2 skills, which use a lot of energy, to not still being immune (and they aren't long buffs either).

I guess it's better than nothing. Gotta work with what you have.

It's been discussed before but I'll bring it up again. The problem with stacking these isn't so much the damage. All of the -dmg reduction traits do nothing for CCs/soft CC condis like Chill, Cripple, Slow, Immobilize, etc. These ends up killing you due to being locked down. It doesn't reduce their effectiveness. It only reduces the damaging condition.