I believe the Shroud to be spores. Tiny, almost minuscule fragments that spread through the air... now condensed, heavy, and potent.
They cling to airways, eyes, fur, and skin. They spread.
The fungi release these spores upon contact, but their roots might've anchored us for a long time... We awoke a slumbering malady at the earth's core when we built the first Well, and distilled the first Elixir.
The Mysterious Wanderer opened the floodgates to ruin.
- V.T.M.