Nice concept, but the rocks near the light source should be shaded at the top, not at the bottom.

 Bad dithering, bad shadows.

Thanks CELS, I'm not sure what I was doing when I made the rocks, as I made them early on, but I was probably trying to make the "dark" part on the bottom, be like the underside of the rock, to show them sticking out at an angle. I'll make sure to change them soon.

I like it, and it looks like a really interesting concept, if the candle is part of the gameplay. I do echo wuhu's thoughts about the background. It's hard to understand what I'm looking at. If those are rocks sticking out of the cave wall, why do they all have a light source above, regardless of their position relative to the candle?

I would love to see this developed further, if you have time.

Looks like you combined two challenges in one!

I would probably try to lighten the background, and i think there is an opportunity to do some lighting effects on the background rocks, which may be too tedious.