I found a similar question to this, but I'm not sure the answer applies here.
The question asks if DOT damage stacks (specifically single target debuffs) and I'm wondering if area effects that deal DOT, like the poison trail left behind by the Witch Doctor's Zombie Charger or his Acid Cloud, can stack.
Enemies that take damage from these area skills aren't affected by a "debuff" which duration can be extended, so I'm thinking the area damage skills may stack where they overlap each other.
Please confirm/disprove my theory
Best Answer
This depends on the skill, as already said the Blizzard skill of the Wizard does NOT stack, it even says in the tooltip. But for example the Hydra with the Venom/Poison rune creates poison pools that do infact stack, that is why that skill is so vital especially in Inferno.