On Dragon Age, we were sometimes given 'free' weeks to experiment and try something new for the project. One of these weeks I wanted to see if I could get some rough basalt models working. I had taken a holiday in Iceland, which is covered in basalt, and that really inspired me. I wanted to try something that mixed in with our regular rocks, to give cliffs and caves another element of visual interest. Everyone was pretty happy with the result, so they made it in to the final game. I was pretty happy with these after a week. I believe this was just using three basalt models rotated and scaled in different ways.
Dimitar Tzvetanov was responsible for the larger rock models which my basalt work intersects.