Very nice. I love the clarity of your style. I feel like the size of the grass blades should shrink more as they get closer to the horizon. As is, the grass is large in the foreground, but then stays a pretty constant size (it diminishes some, but not enough). I only mention it because it robs the piece of a more 3 dimensional feel.
Also, it looks like you saved this as a jpeg somewhere along the line (thus the ridiculous color count and the fuzziness on the edges of things).
HOLY SHIP that's a lot of colors. 31882? I think you could cut down on those. None the less, it's a very good pixelart piece, but I think I read that the size limit is 800x600. You need to take away 6 pixels of the hight.
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