Nice dramatic shading.
biggrin The mouth area looks a bit confusing to me... I'm not really sure what's going on with the upper lip area and the teeth. The chin could be a bit more defined, but that's just my personal opinion. x3
As for the hair... it is a bit blocky.. hmm. I don't suppose you've seen the Samurai 7 DVD cover art? It kind of uses a blocky/simplistic style, but it still has a lot of flow.
Hopefully they'll give you an idea of what I'm talking about.
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