The Maw: Destroying Alpha Halo

Destroying Alpha Halo requires using the wreck of the Pillar of Autumn as a weapon. Cortana develops a plan to overload the ship’s fusion reactors, creating an explosion powerful enough to break the ring apart before 343 Guilty Spark can recover the Index and continue preparations for activation. This episode examines the final battle through the Autumn as the Master Chief fights Covenant forces, Flood forms, and Sentinels inside a ship already lost as a functioning warship. The destruction of the reactors creates one last race across the vessel before detonation. Most UNSC personnel who reached Installation 04 never leave it, and the Chief initially appears to be one of only a handful of survivors. The explosion destroys Alpha Halo and prevents the immediate firing of the array, but it also scatters Flood-contaminated wreckage and Forerunner debris across the system. The Battle of Installation 04 ends not with occupation or surrender, but by denying everyone the battlefield itself.