[quote][b]Posted by:[/b] Jump Into Hell And the humans found a cure to fight back the Flood. They were able to eradicate the Flood, so that it would not be a threat until thousands of years later.[/quote] Only the cure was later discovered to be fake, as the Timeless one (a Precursor) reveals that the Flood simply chose to stop infecting humanity because they passed the 'test' the Precursors created for the Mantle - which involves having to succumb to the Flood, since it's viewed by the precursors as the perfect life form. Humanity passed because, in a last ditch effort to stop the Flood, they threw a massive amount of their population against the Flood.