Really neat photo-manipulation.
I love the pose, its like a striking snake in a way. Really brings out the sinister feeling of a death eater. Reminiscent of Voldemort's ways.

Though i think your model looks a bit 'clean' to be a death eater; maybe a more sharper and angry expression is needed as if shes really speaking the words of 'avada kedavra'
but thats just my opinion. Maybe shes a relative of lucius malfoy XD

I love the hair and your lighting, the glowing green reflecting off the spell. Its all put together really nicely. This has got me even more anxious to see the upcoming movie.