Box Jellyfish

I think you shouldn't be so harsh to yourself. The idea of box jellyfish is amazing, it didn't cross my mind when I was creating the ,,poison,, for the challenge. The movement of the jellyfish is great too except the movement of the legs. If you add more frames to the leg movement it would look more smoother because now is kind of wooden. The colours would be better if they won't be so bright but more subtle. Also the most important thing is just to practise a lot, maybe read some pixel tutorials and some articles about pixels.
I am doing pixels for really long time now, but they still aren't on the level I want them to be, which can be frustrating sometimes.  
I am not good at giving critiques, because I am not a native speaker and it's hard to put everything I want to say into words with right terminology and I  also feel bad for criticizing other people's work, but I hope you will get something from my comment.