This is a great challenge, but it would be a better challenge if you asked people to draw them without their hair. That is a key distinguisher, and in a lot of modern cartoons (predominantly anime) it is the only way to tell characters apart. Without hair, it would force people to really look at the facial structures of their characters, without relying on hair to make them original or different looking.
I, uh... may finish it later. But for now, this is what I got.
it was fun, this is an interesting challenge
/runs to SAI
That paused my rampage of stumbling around the house like a drunk man for a whole two minutes.
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