This is my first critique so forgive me for any mistakes and errors
Vision: I believe you executed what you were trying to do quite well. A tree blowing in the wind while leaves fall. Though the execution is done quite well it does seem a bit off. This may just be me but it seem like the tree doesn't flow as naturally as it should. Though it still looks great and it's better than anything I can do. Though the falling leaves are done excellently.
Originality: I say this piece is really originally and not something I would expect to see at a first attempt to make an animated pixel icon. Though I'm sure I've seen something similar before.
Technique: Everything on this piece you executed really well. The only thing that I see flawed is the tree doesn't seem to be alive. It seem like the top of the tree, where all the leaves are, need to move more. Sadly I can't really give you a suggestion on how to make that possible But overall the colors and the scenery is rather excellent, especially for an icon.
Impact:This had an nostalgic effect of me and brought back fine memories of Nes gaming. Even though I stated before about the tree didn't flow as well as it could. This icon still seem like it could of been part of a game. Especially during a intro cut scene in a NES game. It's a well made Icon and you can tell you put a lot of time and effort into creating it. Well done c: