its a good start
WHAT IT NEEDS IS MUSIC!!
You know when a stick man kills another, a few of them you it so that they don't move anymore, they need to keep moving, they can't just stand there and wait to be killed.
Also. Clean it up a little; the paint strokes are a little un-even.
Also, for the weapons and explosions, add a little more detail to them, make them look like weapons, and not just some lines filled with colours and what not.
Like I said, this is a good start. one day maybe you'll make the front page.
A little advice though.
While making your move, be VERY picky ABOUT EVERY LITTLE THING. Music, animation, WEAPNOS, everything. Adding detail and what not. also If you want your flashes to get better, look at other stick man flashes and watch them carefully. And if your work is no where near as good as theirs then go back and redo it, and keep doing that until it comes out the way you wanted it.
KEEP UP THE WORK YOUNG ONE! ONE DAY YOU'LL HAVE YOU DAY IN THE SPOT LIGHT! :)