The result is a combination of both - like you get with a bevel hill.

There are 3 ways to make hills in this style.

They're solid grey, just a bit darker than neutral grey, and because they are mapped symbols I can use an Overlay Blend Mode to make them take up the colour of the terrain.

The blend mode does odd things around the edges if I feather the edge of the symbol, so the EFI after the Blend Mode is to soften the base and help the hill sit into the terrain.

They're relatively simple map files, exported from Blender. I made a material that could mimic a map file and put it on a very simplified 'Landscape' object. The blue part of the map material is a simple blue material that reflects more or less light from the 'BLUE SUN' directly above it. The red part of the material is a radial gradient based on the normals of the object faces, and expressed as an emission, rather than reflected light. That way it stays constant depending on the direction each face is facing, and regardless of the sun.

The grey image is a gradient material that maps only the parts of the ladscape above a certain point.

They don't really change the shape of the underlying hill because all of them are transparent - sort of. I added the second sheet so they could be put closer together than they can on just one sheet.

That's why I need to try and get all the most useful shapes ready made.

Yeah, roundish or shorter would be good.

They look weird if they overlap on the same sheet, but ok if you use a second sheet for the ones on top.

In a top view style there's not much point in overlapping them too much. It's not like an isometric view.