Battle of the Maginot Sphere

"Something is wrong! It's moving away! At night I can see it—flitting shadows—black against the stars. Thousands of ships! Not spiraling outward, but heading for the line! This is the tipping point, Didact. It's no longer feeding. It's coming for you."

— Librarian to the Didact

The Battle of Maginot Sphere was a naval battle in the Forerunner-Flood War. It marked a turning point in the war — the Flood had stopped feeding and expanding, and instead, were devoting their efforts to penetrating the last Forerunner line of defense, the Maginot Sphere, to complete the destruction of the Forerunners.

Prelude

Mendicant Bias

The battle was preceded by the rampancy of the Forerunner artificial intelligence Mendicant Bias, who after a protracted intelligent conversation with the Flood, had decided that the Flood were the next step of evolution for galactic life, and that the Forerunners were corrupt for resisting this inevitable evolution and for refusing to be supplanted by their biologically superior adversary. Mendicant declared his allegiance with the Flood and defamed the Forerunners, and not only lended his tactical intelligence to the Flood, directing their fleets, but also gave the thousand Forerunner-crewed vessels under his command to the Flood. However, his intelligence was tinged with madness, against blind fury for the Forerunners for their obstinance, making his actions predicatable and thus easily counterable.

Invasion

Shortly after Mendicant Bias assumed command over the Flood forces, he began ordering termination of the Flood's feeding and exponential growth, and instead, Flood forces were marshalled to penetrate the Maginot Sphere, the Forerunner final line of defense for their inner colonies. If the Maginot Sphere was penetrated, the Forerunners would be destined for death, thus making this attack an influential battle that would decide the course of the war. Whereas previously, captured Forerunner supraluminal ships were sequestered and unused in the Flood war effort, now, Mendicant Bias recalled all of them to attack the Maginot Sphere, and the gathered Flood attack fleet was over 4.8 million vessels, although the majority were non-military, and an extremely small number were capital-scale warships. The Didact, who was able to predict where the Flood blow would fall upon the sphere, was able to marshal the Suppression, Security, and Emergency Circumstance fleets, with a total of over eleven thousand vessels, with the Flood outnumbering the Forerunners 436.6:1.