today i started with an easy head to do exercises with the pen...
what do you think? xD

There's a seam on the back, you might want to fix that.

I am a fan of the glowing lines, but I can't really see a face or anything.

Very nice - I especially like the side.
At first glance, the back and top seemed a bit too similar, but when I looked more closely, I could tell the differences.
I like the patterns on the edges of the front, and the eyes are great, but the nose/mouth seems too low.
There's also a seam.
8/10. Nice job.

EDIT: Ninja'd.

thanks for the comments ^^
about the line in the back... i don't know why i everytime get that thing Oo

To be honest i think that the current top would look better as a front piece than on the top. And it isn't really tribal it is just random glowing lines.

Seems cool nonetheless. 7/10

nice
one advice if your using a pen
add more anchor points to smooth out some sharp turning points
and add something to to back, so empty there

:/ there is a sean on the bak.... fixx THAT!!!!!!! 6/10 because of the sean...

I like glowing lines
Loved the side and front
8/10

The glowing lines effect was a nice choice. Some things I don't like about this piece though, is the face. It looks ok right now, but I feel you can do better. As someone suggested previously, raise the mouth and nose. The sides and back really stand out at me, they look great personally. But for the back, you really should fix that seam.

Too be honest, this looks quite trippy. Keep this up, and you soon will be making pretty skilled heads with the pen. 7/10 here.

cool exersize..
ok nao about the line. When you r mirroring, look carefully at selection options u r using.

Has to be:
Radius, smooth, feather = 0. contract expand = 50. contrast = 100.