Direct death is never the plan. It shows up in statistics. I noticed a burning smell that I now think is similar to other reports. Sulfur or electrical burning type smell.

Anyways, fog rolls in every one dies the next day is too obvious. They will paper cut humanity to death. 1 shot or encounter will not be enough... they want to have the effect play out over time. Any mass deaths will be delayed from any event; aside from direct war.