Hey! Nice progress there Vermolius.
Heres a tip for you.
Don't be scared of playing around with the hues of your piece. Sometimes it takes a good while to tweak, but the end result is worth it. Think about different colors that can be used for shadows and highlights of a color.
Your main color is red in this piece. Purple is a great shadow color for red and yellow is a great highlight color.
For green yellow can be a highlight and blue a shade. Same goes for other colors as well.
Heres a quick edit to show you just how much more depth a nice color palette can add to your piece. All I did was change the hue of all your shadows and highlights. No saturation or lum(ination?) changes.
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One on the far left is your original. I personally prefer the middle one, but don't think these are complete! I'm only critiquing the coloring, and my edits only took about 2 minutes so play around with it and study other peoples pieces to see how they go about contrasting their shades.
I just noticed I didn't touch the cape! sorry!
Also just curious, what are you developing the game in?