What are those fossilized rings on the ground? I know Halo is full of mystery, etc., but for Halo fans they evoke the fallen space elevator, which is totally out of place on an halo ring. If they're Forerunner why aren't they smooth like every other piece of Forerunner architecture? Not trying to be overly critical, but when I get into the artist's head, they seem like kind of lazy iconography executed without much thought.