I thought it was like some kind of exhaust, since he's in a gas mask and all. I like it.
When he's stepped forward, why does he lift his backest foot up before he steps back? I mean, it seems like he'd do it while he steps back, as opposed to before. Just a question, though.
Anywho, yeah, this rocks. I didn't know it could get any better than it already was, but it has.