Nice job

 Love it, I was also struggling with the idea of showing a normal portrait of a Ninja. 
They don't just pose for pictures 

Awesome style! very readable. and nice usage of colors.

Thanks! I've made several changes since the original upload. I enjoyed doing this, and I've started doing an evil robot too.

Hah, nice. I think the sky could be darker to make him seem a little less obvious, but it's pretty good!