Powder Passives

So, i question whether the passive stack per spell used. For example. I use meteor 4 times. costing 3, 4, 5, 6 mana. So, when i have a double tier 6 passive, would I have the 3 mana costs for 3 seconds, not refreshing until its time is up, or will it stack additionally, or maybe it'll just take the highest value, i have no idea.

 

i dont think u loose mana when u do powder special/passive
EDIT: oh , u cant have the 3 mana for 3 sec as far as i know

 

i dont think u quite understand what i mean... i mean... i mean that as the value for the passive. For example, the passive increase ur damage by 5% per cost. it would be 15% extra damage. And what do u mean i can't have 3 mana for 3s? the passive literally says, effect last for 1s per mana cost.

 

oh , then idk :/