Exactly. I would love to be able to make smoke coming out of chimneys for instance. Thin fat start, then widen and get wispier. Just have them read in a box and set them over the house.
Anyway, here's another iteration. I had to clone out (only) a few exploded stones, as they were restricted by a painted shader, which somehow gives a hard edge where dark gray hits black, even when painted very softly. I added 80% tiny blue green fake stones in the foam layer, which already had a reflective shader.