User blog comment:James12708/Reapers VS. Forerunners VS. Angels from Darksiders VS. Humanity from Halo VS. Council and humanity from Mass Effect VS. Imperium of Man/@comment-1786741-20130113205808/@comment-3228423-20130113210734

I think it's something about the Reapers leaving the galaxy to get to a new one and pointlessly slaughtering its inhabitants while they fire the Crucible.

I dunno the exact details, just that it's something stupid and makes absolutely no sense. :|