Just started with my pen with this one.
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Once my line work is down I went straight for the paint and started laying down my washes of color.
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I went a bit more abstract with this one.
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After laying down all my light and dark tone marks I follow up with laying down my flat colors on the skull and the spinal cord.
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Now that those are done I move back in with my pen and sharpen lines out.
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Finally I then take another color and put a little shadow down.
There you have it. On to the next one with a bit more movement.