This was my first attempt at a volcano for a Terragen contest. I generated a terrain with high glaciation. There was only one mountain of any significance in the terrain, and I used the sculpting tools to raise the height and cut the crater. The viewpoint line from camera to target went across the mountain, with a very steep downward pitch. This caused the render to be surrounded by a great deal of black, which had to be cropped away.

The magma and smoke were added using PhotoImpact particles.

I was not really satisfied with this image, because the mountain was too steep and the background not well rendered, so this was not entered in the contest.