The world itself is barren, the sand wiped away most signs of life. However, the world isn’t completely empty. Creatures that adapted survived. So the world is a planet of survivors. The creatures that survived should fit into an arid environment. The colors aren’t verdant and are not too vibrant, but that doesn’t mean the the colors can’t be varied or interesting. Color should be used for emphasis and be striking. Refer to the color scheme document for a base idea of the colors of the game. The ruins themselves draw influence from persian architecture. Think grand structures that stand resolute against time. The technology should influence the design.
Here is the color scheme for the sand and for the ruins. This is just for those two things so feel free to use other colors for other things but if you do try to make sure that it is cohesive or fitting.
The different sand colors relate to how the sand would look in shadow or brightly lit in the sun.
The red in the ruins is meant to be a metallic copper of some sorts.