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-2250460-20121114194727/@comment-1683193-20130110172329

And Onyx Sentenials are tiny little drones a quater meter wide. Forerunner assault mechs can create explosion large enough to be easily visible from orbit.