Needs a bit of practice, but a solid game.
It's pretty fun, the first few times I couldn't pass the zombie stage on easy, but after coming back to it a few times, it can get pretty fun. Addictive, even.
I don't know why I kept coming back, either because of the challenges for the medals, or because it's pretty satisfying how when you hit enemies, the screen shakes and you hear that excellent punch sound.
If I had to say what needed improvement, I'd say hit detection if possible (sometimes you think you're on the right plane to hit an enemy only to whiff) and maybe switching the control buttons around. It's probably just me, but I hit S when I mean to attack and vice versa. Sometimes there's just this weird little lag on the jumping and attacking. Where after attakcing in the air and landing and trying to jump again (to hit the UFOs) sometimes I'd still stay stuck to the ground even though I hit jump after landing, and on top of that, sometimes I'd execute my spin attack without meaning to because of this.
But really, solid game here, lot's of fun. If you could find a way to incorporate some co-op in your next brawler you'd have a damn awesome game.