This is a Black Tree Design „Evil Eye“ which to me equates to a Second Edition D&D Monster Manual picture of a Beholder (see below, a ping pong table tennis ball with pin tacks sticking out of it and a „bitey“ mouth on it): 

As they say, the beauty is in the eye of the beholder (and although it does not compare to the Fifth Edition pimped up larger model of the Beholder) and I like its rustic charm. The other nickname we gave it was „the purple people eater“! Time will tell on that one as you have to be fairly high level to be unfortunate enough to meet and greet one!