I was going to make an animation for the contest with this guy popping up at the end, but with only 3 days left I knew I wouldn't be able to finish the animation in time.
You still have time. I think you should add shine on the eye popping out. I also think you should add some blood on the zombie, or have a piece of skull missing where you can see its brain. Add some shadow where the eyebrows are supposed to be.
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