I've been googling around for a few hours and now I'll just give up and ask... I have a scene that I've upgraded to 2018.3.9f1. Unity created a folder called _TerrainAutoUpgrade and created new terrain layers. They show up with the wonderful pink broken shader color when viewed in the scene. The terrain layers themselves seem to be fine. If I check under the terrain settings I see this: "Ok!" I say. "The terrain is using the Standard Shader. These need to use a LWRP compatible shader!" But if I choose "Custom", I can't assign a shader, a slot appears and it apparently wants a MATERIAL! I can put a material into that slot: But if I do, then the terrain is mapped 1:1 with the material (texture/shader) - which is ridiculous - and the system seems to ignore the terrain layers and the spat map. How do I upgrade the terrain layers to use the LWRP so they work on the terrain? P.S.: There is some talk about selecting "Draw Instanced" as a solution, but no: Draw Instanced simply makes the terrain invisible... and then the psychedelic artifacts come out when the scene view camera is moved.