So guys, heree is the question I'm sure you have all asked yourselves at one point or another: How the f@!k did the Forerunners defeat the Precursors?
Transsentient beings that spanned several galaxies and created basically all life in the Milky Way. They made the Forerunners. They were the daddies, the bosses, the guys-no-one-wants-to-mess-with. And the shitty half-assed society the Forerunners had at the time were able to nearly drive them to exctinction. It just doesn't add up I'm afraid.
What about the huge numbers they undoubtedly had in other galaxies? If they were able to create entire species, why didn't they just create one to destroy the Forerunners? Or better yet, use their mind-numbingly potent neural weaponry to bash them back into the stone age.
Sure, if they were fighting the Forerunners at the peak of the Ecumene's power, they MIGHT have a slight chance to at least control the Milky Way for a while. But all the other galaxies of Precursors would eventually whoop their asses.
Also, on a side note; what makes Humanity more worthy of the Mantle than the Forerunners? Was there anyone in human history who revered life more than the Librarian? Hell, the Forerunners had an entire caste of their society dedicated to protecting life. Sure, they eventually fired the Halos, but that was out of necessity, not choice.
Discuss.