- last post: 01.01.0001 12:00 AM PDT
I think it was neither.
The flood on the halo rings are survivors; the flood survivors of the last activation of the halo rings. At one point, the known galaxy was carpeted with flood, who were in the process of consuming the forunner. The flood's origins are unknown, but thats besides the point. What really matters is that they are the sole cause of the destruction of the Forunner. The forunner had to use the Halo rings, first as a place to study the flood, in an attempt to defeat them, then lastly, as a final weapon. The halo rings destroyed the forunner, and most of the flood, save for the few that were on the halo rings.