Okayy, adding this line if you agree:
"severity of the diseases caused by the miasma depends on how much charge(s) used before releasing it. Niks can also opt of adding another symptoms rather than the severity of the disease. The severity and disease stack on the victim unless cured. In case of paralysis, it stacks from localized numbness (like anesthesia or being slapped really hard for single charge) to complete paralysis (require 5 charges)."

Hmm, I hope I'm not nerfing this ability too much, though, considering the other diseases combination would result in paralysis anyway....