Quote Originally Posted by Neptondoodle View Post
the tutorial says that we're sculpting the land clouds layer, but the mountains cloud layer is still separate from that,
I think you're misreading what it says.
You airbrush the mountain edges so that the opacity is adjusted slowly to the point where the edge of mountains are it doesn't have a huge step in contrast so that the edge disappears. It has the effect of molding the land in general, but you're not messing with the land layers.