A good idea from MK83 the expansion of the landscape tools if possible , creating sharp sided holes or - tops with the shape of a rectangle, circle, triangle etc. Just select a primitive shape resize it what you like for your hole or top dimension you like to create.
I want a small round hole in the ground to hide a cilinder in it, it must be a sharp sided hole in the ground.
For example in a horror game to create rectangle holes in the ground on a graveyard.
