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-4967682-20130116065115

This is a really unbalanced battle. Humanity from Halo is so low on the power scale that I'm wondering why they're here, whereas the Imperium of Man is so high above everyone else that I don't think anyone else is worth considering. Except the Forerunners, since they seem to be as powerful and advanced as the plot needs them to be. Basically:

Forerunners (maybe?) > Imperium of Man >>>>>>>>>>>>>>> Reapers >>>>>> Council >>>>>>>>>>>>>> humanity from Halo

I don't know about the Angels. Never played Darksiders.

A more balanced match up would be, say, UNSC, Council, and Covenant vs Reapers (even that heavily favors the Reapers when you stop to think about how numerous they are...)