Forerunners or precursors. Forerunners did beat the precursors, reshape planets and stars, and conquered planets in hrs with weapons that streak across continents and warriors that razed continents in short time as well. Also factories that produce efficient bots per minute , and harness hard light like a lightsaber (your move STARWARS) However precursors have the indestructible orbital bridges, structures that withstand forerunner weapons(excluding halos ) and then the flood ... [spoiler]most important part to remember is they both have the capacity of GALACTIC destruction[/spoiler]