Commission: Dark Battle

Commission for She wanted me to make dragon versions of her OCs Seraphine [link] (right) and Siren [link] (left) in a battle scene. I think they look okayish XD
I have to say colouring black things realy is difficult Plus this picture would be realy dark if it wasn't for the fire XD
Anyways been practicing that new shading style, and background details I also tried a different (and longer) way to do scales. Do you think it's better like this?

Hope you like

Also I'd realy like a critique for this pic