ZBrush. I imported the stack in, subdivided a couple times, and just used the an image texture of rock to apply to it as an alpha mask, and then you "Inflate" it. It's sorta like if you could slowly apply an image to a terrain, and see it rise, and then just stop it where you wanted. Except, obviously, this isn't a flat surface. AS

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"