- “Halo. It's so new… unfinished. I'm not exactly sure what will happen when we fire it.”
The Raid on Installation 04B was a small engagement between the Flood, the local Forerunner constructs, and the UNSC/Fleet of Retribution alliance.
- Main article: Battle of Installation 00
Rtas 'Vadum rounded up survivors on the Shadow of Intent while Johnson brought the Forward Unto Dawn to the new ring. John-117 and the Arbiter escaped from the Flood infested High Charity via Pelican dropship. Most of the Flood were killed when High Charity was destroyed but a number escaped in Flood Drop Pods, including the Gravemind.
John and the Arbiter arrived in a damaged pelican and crashed in a valley near the control room. As soon as the Control room was in sight the duo was quickly ambushed by waves of Flood. They managed to get to the top floor where the sergeant was waiting for them. They contacted 343 Guilty Spark to open the door. He stated that the Flood outside must be eliminated before they could enter. John-117 then cleared the flood and entered the control room. There they were greeted by the monitor. They were informed that the Installation was almost complete. Avery Johnson then said they did not have a few more days. He then proceeded to activate the ring. Spark knowing that the Ark would be damaged and that his new Installation would be destroyed, then shot and killed the sergeant with his main weapon. John-117 then attacked the monitor with his fallen ally's Spartan Laser. After the monitor was incapacitated, the Spartan took his AI and activated the ring. Sentinels, who were helping to quarantine the Flood, also became hostile to Thel and John.
Finding a warthog left behind by Avery Johnson, they proceeded to the Forward Unto Dawn. Installation 04B began to shake violently apart as it activated. Flood and Sentinels began attacked the duo as they drove over unfinished terrain, but they eventually found the Dawn. They crash landed inside the hangar, activated the ship, and made full-speed for the portal.
- “When Halo fired, it shook itself to pieces. Did a number on the Ark.”— Cortana to John
When Halo fired, it destroyed itself, heavily damaged Installation 00, and destroyed the portal as well. When the portal collapsed it sent the fore of the Forward Unto Dawn to Earth and the aft was left drifting towards Requiem for 4 years, 7 months, and 10 days. John-117 went into cryo sleep while Cortana was left alone to eventually go into Rampancy. The Arbiter attended a memorial service to those who fell in the Battle of Installation 00 and the war as a whole before returning to his homeworld with the rest of the Sangheili forces.
It was later found that 343 Guilty Spark, who was thought to have been destroyed, survived the battle. He sent a distress signal that was picked up by the UNSC, who dispatched the scout vessel UNSC Rubicon to investigate. Spark was retrieved and he told the crew his life story before they jettisoned his body into space. However, before they did, he uploaded his consciousness into the ship, shut down its A.I., and put the crew into cryo-sleep. He then began piloting the ship to the Librarian's theoretical location.
- This was the final engagement of the Battle of Installation 00.
- This battle ended like the Battle of Installation 04. John-117 destroyed Halo, made it to the ship in a warthog, and got away before the Halo ring was ripped apart.
- It is odd how the Arbiter made it back to Earth as he was in the bridge which is in the back of the ship which got stranded in space with the rest of the ship heading toward Requiem.
- Halo 3 (First appearance)