Hey there, just wanted to get some C+C on this. I'm having trouble getting some REAL feedback on it. Everywhere else I've tried were just "that's cool, bro" and the like. I want some brutal honesty, since I plan to maybe sell this game when it's done.
Yay! That's just the kind of attitude I like to hear.
I like what I'm seeing so far. You have a good feel for human construction and you effectively utilize light and shadow to render form. I think the animation could use polishing but right now I want to address the anti-aliasing.
People are telling you to anti-alias, but you already are! Those dark pixels you've placed on the legs are a form of anti-aliasing. The problem is that the intensity of the effect is determined by the background. On white it's garish, but on a darker background it looks much better. Let's take a look at your guy at different extremes:
Take a look at the different visual effect the dark pixels on the legs give for light, medium, and dark backgrounds. When people are telling you to AA it's probably because the AA you do have doesn't work so well on pure white. Those dark pixels soften the form of the leg on dark, but they turn into jagged little eye-stabbing daggers on white. I've heard people refer to it as the cardboard cutout look.
But there's one very important thing to keep in mind. Since this is for a game, the character probably wont spend too much time on fullbright colors—there will be trees and buildings and trashcans and other things behind him—so the dark pixels will blend into the background better. There is a world of difference between posting a sprite on a white background on a message board and sticking that sprite into a videogame. One helpful tip, at least here at Pixelation, is to use a transparent background when posting your work. This theme happens to have a nice neutral background which works well when posting things like character sprites.
I'd say you can probably keep the AA as is and it will look fine ingame. But while we are on the subject, let me offer an alternative direction. I was writing this while Crazy posted his version, and I think it'll be useful to see a couple of possible directions to take.
I have for the most part dispensed with the AA and instead relied on colored outlining. One useful thing to keep in mind is that lines can be rendered with different weights using color and value, so lines around the bottom of a form can be darker (heavier) while lines towards the top can be lighter (thinner). The sprite still gets some anti-alias effects on the dark background for free, but it stands up better on the light background.
The messy palette seems to be from the processing of turning the sprite sheet into an animated GIF. Weird things happen in certain frames like shadows becoming lighter and darker. It looks like the sprite sheet is using a more consistant palette, but there are a few wonky areas like the hair seeming to have it's own palette and the outlines of a foot turing blue mid-kick. Watch out for stuff like that, too many odd colors can make your art look sloppy.
