Fantastic!
I think I've discovered a hidden gem in the Newgrounds Portal. A great idea -- a simple "level" of Doom played out from a side view. I hope you continue to make these levels.
I would like to see more of a story, however. There is little more to this than the Space Marine shooting stuff. There doesn't seem to be any reason for any of this (though I haven't seen the first episode yet so perhaps more is explained there). I wish it had gone on longer, as well. The ending was climactic enough, but it left me feeling cold and alone, and a little damp.
Make more!