At first glance I was 100% sure this was your work. The pose is very nice, but man you need to figure out some more basic figthing stances, as you use this same stance/pose in almost every anim you create ;) Still good, though I agree with the guys below, one more recovery frame would smoothen this out considerably!
I like the single-frame slash. I have tried something similar, and I can say you can't cut such an attack in two character poses : if you start detailing, you'll need at least 3 or 4 extremely fast frames, and then you bump on the problems of GIF support with fast frames.
In a game with such character I would add some recovery frame(s) however, even if I'd skip them if the players keeps re-attacking.
Nice flow, my only op is to have a little delay on the last 2 frames of the slashin, or add frames for the recoil....
Anyway, it looks great
Aye, its nice but I think it slightly suffers from the same problem the original Strider sprite has from the videogame of the same name. The 'swipe' is depicted as a whole sweeping arc in one frame,
I think it might look better if there was an extra frame at the end of the swing and you draw the arc over two frames ( or even draw it in a second frame less pronounced and trailing near the end of his swing). The anticipation frames at the beginning are lovely.
He is here to be the c-cc-ccc-combobreaker!! xD It´s good when attack is so fast, but the ending of the animation is a bit weird. Hard to figure it out..
He's very feminine and has some boobs happening, if you didn't say it was a guy I would have assumed he was just another awesome girl from you.