At Verdigris the big building challenge was that I could not change the terrain textures since the 4 sims were connected, and any change I made would have affected all 4 islands. So, I had no choice but to eliminate topography altogether by flattening out the terrain and placing a big floor that concealed the default terrain texture which was not something that I could work with.

This brought about the underwater level where I placed big rock formations and plants on a completely flat surface that was made out of concentric black and white squares.