After years of combat with the invasive bio-machines from Andromeda, Nathan Myers and the crew of the Legacy have acquired startling intelligence from their latest Prule engagement. The Bio-machines and their proxy races are gathering technology plundered from the Milky Way galaxy and withdrawing through the Guardian Gateways to unknown locations. The reasons behind the unexpected Prule strategy has Nathan and his crew searching for answers. Justice, the AI of the Legacy, has suggested the best way to obtain accurate data is to pursue the Prule through the gateways, and if possible, make it their final destination. This revelation could not have come at a more inopportune time. Another conflict has one of Nathan's allies embroiled in hostilities on Alpha Base's doorstep. The shooting has started and the confrontation is escalating exponentially. The Chaalt Military Council has warned Nathan, if the warfare continues to propagate, he must abandon Alpha Base or be caught up in the rapidly expanding divergence. The probability of being dragged into an intergalactic war, and the uncertainty created by the sudden change in Prule tactics, have Nathan facing his biggest challenges yet.