It's not actually a patch. It looks like whatever it is, is holding the moving eye in the socket. If you notice the 'eye' is protruding from that 'patch' and is an entirely different colour to his other eye. Therefore, it's not just a bog-standard eye-patch.
You can't really comment on the back or face in great detail because this isn't a clear picture.
The lego version of Moody has the same feature.
Quote:
Imagine the final scene at King's Cross station where Moody intimidates Vernon Dursley by showing him his eye. I think that would work well.
Isn't that in OotP? *brainfart*