This is awesome. How did you guys make the single shading? Is it post process stuff? Great work !
Thank you very much! We applied a toon shader to most things in the game (Some just use an unlit solid colour shader) and we very carefully tweaked it so that it only ever renders the same colour as the background when lit and a second shadow colour where it's facing away from the light. We sometimes had to battle some of the engine's features (like anti aliasing and shadow quality for example) to eliminate as many aspects rendering steps between those colours as we could. No post processing was used at all.