... Also known as the "Final War".

The final climactic war waged between humanity and the Melconians, which reached genocidal proportions with use of worldburners and unrestricted biological and chemical warfare by both sides. Both the Melconian Empire and the Concordiat were destroyed, along with Terra, but a number of human colonies survived the war, as did at least some of the Melconian population. Nonetheless, hundreds of billions died on both sides and large sectors of the galactic arm were effectively depopulated and rendered unfit for any life-form ( save for a few Bolos on random and certain (Operation Seed Corn) planets.