They used Dark colors in the distance, and they used lighter up front, to create that 3D effect on it
The answer to your question is pediments.
Mesopotamia means the land between two rivers since cuz of the Tigris and the Euphrates. BTW search on YouTube Mr.Nicky’s Mesopotamia song. It helped me when I had to learn about this in 6th grade.
The main villain of the 100 Clairvoyants is Votimer Kyminius Plod.