Thanks for the feedback guys.
Cheers Dandello. (forgot to say, I'm using your crack system here too! many thanks!)
Cool suggestions Dune.
You are right, I forgot to turn on ray trace shadows in the atmosphere!
The grainy ground is due to low sampling, and quick texturing, needs a bit more love and care.
Thanks for the lighting and layout ideas too, I always wanted to avoid having lava in the scene (sorry jbest), so am looking for something a little different and a bit of destruction might be fun!
Yup, same here, camera projected masks for the smoke, a bit fiddly but does the job.
Here's a grab of the volcano model in zbrush.
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