You're kind of an asshole.

These sprites have been on the site for months, and you clearly have some vendetta against his works. I dare say this one may be close, but come on...Nemesis from FF6? Because the shading is similar? I think you are reaching. Honestly, if there was a real issue, it would have come up by the devs on the site either way. 

Flag his "suggested edits", but don't outright ban him because of false accusations.