Not one critique yet? Well let me be the fist. Impact is stunning especially with the balanced, almost symmetrical design that is cast by the overhead moon and Nightmare Moon's form. Yet Luna pulls away from that, causing her to be a center-point even with the dark colors. Her sorrowful expression thus cannot go unnoticed. The choice in colors is limited with only three but causes a great vision especially with the wet hair soaking in the ground. Only technique error I can see worth critiquing is the lack of shadows from the overhead light source, the moon. Well done.
I love the art style here, it seems a bit disproportionate but fits with the overall mood. The contrast of soft curves and jagged lines really shows something. I like the idea of Luna coming to Nightmare Moon as a shoulder to cry on rather than Celestia. The big things that strike me- Nightmare Moon's shoe, the black water, Luna's tears and the way it all glimmers. Now I'm half asleep, can't go to bed, so I'm hallucinating slightly. Nightmare Moon's wings- this picture is so vivid that they actually wrap around Luna. That doesn't happen so often. Usually characters just wiggle and blink. One thing that confuses me is their position in space, but it's more or less insignificant- They can float aimlessly where they like.
This is....wow. I can't even begin to explain how beautiful this is. It's screaming words at me that I cannot even comprehend. I love the concept with this. I really do. This is just....wow, so brilliantly wonderful.