This is very good! I love it! First of all: I love the lighting effects. You really captured the "creepiness" of the scene quite well. I also like how Zim's eyes look with the various light reflections. It makes him look all the more menacing.
On originality, I'd have to say that it's pretty good. You used a shot from the actual show, though, and didn't create it on your own. Nonetheless, it's still a great picture!
Technique: Very good as well. The way the lines in the background contrast with the looming figure of Zim is very nice, but, like I said, this is based off of a captured shot, so the technique still isn't completely original.
All in all, though? Great job. I am adding this to my favorites!
Where to start, overall this picture looks amazing, I love the fact that you captured Zim's evil figure and not only that you match it with the darkness of the room. There is one nit picky error that I see and it's Zim's right arm or if you're look at the picture the one on the left, it's strangely long for some reason and the shoulder seems to sag abit...and also the way Zim's arm curves like that makes it seem like he has not elbow joint, it just doesn't seem natural...but after all it's a cartoon character so I could be wrong. The only other thing that bothers me in this picture is the window, maybe it's just me or it looks alittle wonky near the end.
But like I said everything went really well for this picture, the shading matches the evil atmosphere, I say you did a really fantastic job.