So I decided to step in for the challenge, and when I read the terms this instantly came to my head.
This is based on this GIF (for those that don't get it)
@MikauKahn: well' I have to confess I used alpha blend for the shading, and GraphicsGale seems to turn that on a weird dithering when turned into a GIF.
@solrac: this dog in particular is, you can see it in the gif link on the description
Your picture is very cute, but I'm not sure if dogs and cabbages are really enemies.
Clearly these two are the greatest of foes.
Also, the palette you chose is very lacking. You should use more contrast, and instead of directly using darker/lighter shades, try making the darks more purple/blue and the lights more red/yellow.
Finally, could you make the background transparent?