Here is a robotic character design made in Adobe Photoshop.
The same character finalized both as a simple flat design with a line art and as a semi' realistic design rendered with a more painterly approach.
In the end I choose the semi-realistic version of this character to develop a scenery that goes with it.
Here we can see some of the exploration sketches in the beginning of the project.
And here are some of the color combinations I tried before actually getting into rendering.
Here in this scenery concept I go with a more flat rendering approach to make a contrast between the background and the character.
The parallax effect created in Unity.