Hi.
One feature I think would be good is the ability to make caves/tunnels through mountains. One way it could be done is to be able to cut through the mountain/hill to create cave/tunnels. Or the other way would be to allow the user to be able to build their cave/tunnel and then use 'shape mode' to build the mountain around the cave/tunnel.
I have converted Cosmic Prophet Cave Kit (which is freely available now) over to GG for use in my game as I wanted to create a cave in a mountain but was unable to, so if possible, I think this would be a good feature.
