You mean the bumps in which the balls are resting? Anyone can make them. It's very simple. It can all be done in the terrain editor. First you take a big brush and paint a big dot. You then have half a sphere standing out. Then you take a smaller brush, set the terrain height lower and make a crater in the big half sphere. Then you do some erosion over it and voila. Done... Understandable? I used one of the standard (little tweaking) bryce materials as snow.