I have seen quite a lot of pictures on DeviantART of gasmasks, and I am aware how hard they can actually be to draw.
But this is a fantastic attempt of one of my hardest charcters to draw. Not only does the facial look of the eyes make the character seem evil, but the colouring used and the wisps of shadow rising up make the pic even more menacing looking.
I can not actually give any room for improvement, except maybe only the eyes themself are red and not the skin around them, aside from that, it's great, thanks dude!