The game is a sort of a mix of Missile Command and tower defense, where you control a bunch of dinosaur sporting a variety of weapons and trying to defend themselves against the incoming waves of meteors.

When figuring out the lighting and rendering settings for the characters, I started with a pretty basic setup of one sunlight, and ambient occlusion enabled.

This setup looked alright but the direction of the light source seemed too obvious, and I figured it would look strange in any environment that wasn't outdoors.  I needed something a bit more neutral.

I played around with toon shaders to no success, then eventually settled on a solution using Blender's compositing nodes system to combine certain render passes and exclude those I didn't want.  The final composite is a combination of the colour pass, and the shadow and environment passes at 20 and 25 percent opacity, respectively.

The shadow layer gives some basic definition to the shapes.  The environment layer provides distinction between adjacent shapes of similar colour, and also shows details like the fingers and toes.