i really loved this piece, i just want u to know ur doing great
on the other hand, i can tell the proportions are inconsistant and unnatural
for example, in the 2nd face (going top to bottom) the thing that caught my eye was the forhead. there barely is any and it really seems unnatural and improtortionate
same thing at the top one, the chin looks 2d, and within the whole peice itself it looks 2d in a few places
i recomend more 3d shape studies, as well as guidlines
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