I'm trying to always include shadows, because I think it adds depth and texture to the backgrounds. But when you add shadows, you have to think about where the light is coming from, and in most of Critters, there is no light. The Critters are mostly in total darkness, using darkvision. I treat the darkvision like an ambiguous glow around the characters, or whatever they're focused on, with shadows away from them. I hope it works. At least for this chapter, the light source is coming from the fire under Sally's cauldron.