Bleeding, Burning and Poison damage
Each stack deals 2 damage plus 4% of your Power every 1 second, before the target's defense. Stacks from you and your allies add up.
The rule
per stack each tick = (2 + 0.04 x Power) x (1 + bonus / 100)
The bonus is your Bleeding, Burning or Poison Damage stat. A creature that applies stacks uses 1% of its Power instead of 4%.
Each tick then loses the target's armor or resistance by the usual rule, with no critical roll. The tick is not rounded, and it deals at least 1.
Poison uses the higher of your two Powers and the higher of your Physical and Magic piercing.
The game counts ticks on a one-second timer, so a tick lands on the first frame after each second.
Bleeding
Burning
Poison
Example
A new Echo Weaver has 10.5 Physical Power. One stack of Bleeding from it deals 2.42 each tick. At the cap of 10 stacks that is 24.2 per tick against a target with no defense.
Raising the stack cap
Some skill nodes raise the cap for the stacks you apply.
Bleeding: 
Blood Borne, 
Bloodkindled Focus, 
Bludgeon and Bleed and 12 more
Burning: 
Blightfire Quiver, 
Emberborne Adept, 
Emberecho and 3 more
Poison: Blightfire Quiver, 
Envenomed Aim, 
Master of Afflictions and 6 more
Stacks that protect you
These stacks add resistance to you, so they cut damage over time and normal hits of that type alike. The last column is the damage removed at full stacks with no other defense.
| Effect | Per stack | At full stacks |
|---|---|---|
| Frostbound Ice Resistance | +0.02 | 0% |
| Inoculation Decay Resistance | +2 | 16.67% |
| Kindled Fire Resistance | +2 | 16.67% |