Dark Elf Rogue Sketch

Here is a sketch that I intend to turn into a painting. I am not going to go lineart on this one... Should be fun.
I threw some quick value practice on it, but the values are probably too light. I have a hard time working in just black and white without a reference, so it's definitely something I need to practice. At anyrate, here's a work in progress.

I imagine her in some sort of subterranean cavern, with lava poring from the ceiling in the distant background... Her sword will have some cool glowy stuffs on it too.

Thanks for looking!