RELEASED: July 10th, 2018
The UNSC Pillar of Autumn flees the Fall of Reach, only to stumble across a Forerunner construct known as Halo. Covenant forces have already arrived in the system, and attack the Pillar of Autumn, forcing it to crash-land onto the surface of the Halo. Fireteam Raven launches using their drop pods onto the surface before the ship crashes, and fight the Covenant forces on the surface to help the UNSC establish a base of operations. During the battle, the Flood are released, and begin taking control of the Halo's surface, forcing the UNSC and Covenant forces to retreat. John-117 is sent on a mission to detonate the Pillar of Autumn's reactors to destroy the Halo, and Fireteam Raven assists by holding off the approaching Covenant, sacrificing themselves to help the Master Chief complete his mission.
Fireteam Raven takes place on the Forerunner construct known as Alpha Halo or Installation 04.
The UNSC Pillar of Autumn is the ship that gets humanity to its first Halo, but it is sacrificed to stop the Flood.