Keep original node lighting after using a light for another node

I am attempting to give my island more of a "3D" effect, as you cannot see depth in the grass hills.

My solution was to place the lights in the scene. I have placed a spot light above the island, however, the rock underneath is now black/really dark. I would like the rock underneath to be unaffected and stay lit. Here is what I have so far:

Even when placing an ambient light in the scene editor, it does not help at all with the rock (but slightly brightens the grass by a tiny amount).

The lighting model I am using is Blinn.

How can I keep my rock like it's original lighting?

I figured out to the answer to this very quickly after I made this post, even though I was stuck on this for about a day. It was actually very simple.

All you need to do is go into the original island scene file, and click on the rock and access it's Material Properties. Then change the lighting mode from Blinn to Constant:

Hope this helps anyone from the future, as there haven't been any other posts I have found about this before! :)