Raid on Installation 08

The Raid on Installation 04B was a small engagement between the UNSC-Seperatist alliance, the flood and later the Forerunner sentinels acting under 343 Guilty Spark's orders. It took place immediately after the raid on High Charity.

Battle of Installation 00
After realizing that the Prophet of Truth had gained access to the Ark, a joint UNSC-Covenant separatists attack force was sent through The Portal to combat the Covenant Loyalist force there, and stop the Covenant form activating the Halo Array and destroying all sentient life in the galaxy.

The combined forces of the UNSC-separatist alliance was enough to completely destroy the Loyalist forces and prevent the Halo Array from firing. However, the arrival of the Flood hive on High Charity changed the battle. John-117 set out for High Charity. His goal was to retrieve a copy of Installation 04's index from the captured AI Cortana and fire off the newly rebuilt Halo, completely destroying the Flood in and around the Ark.

Raid on High Charity
John-117 Landed in High Charity and combated Flood forces deep into High Charity. He found Cortana, and therefore, the activation index. After this, he set High Charity's reactors to explode. John and Thel 'Vadam took off in a Pelican to activate Installation 04B and destroy the Flood. As they left, High Charity exploded, killing nearly all of the Flood there.

Battle
Due to high damage, the Pelican crash landed near to the Installation's control room. Meanwhile, Sergeant Major Avery Johnson landed the frigate Forward Unto Dawn on the Installation, far away from the control room. John, Cortana, and Thel 'Vadam made their way to the control room. At the same time, Flood dispersal pods landed on and around the entrance to the control room. John and Thel fought through flood forces with the help of local Forerunner sentinels. At the top of the tower, the team met up with Sergeant Johnson, secured the area and entered the control room.

Inside the control room, the team began to activate Halo immediately. After learning of their plan, 343 Guilty Spark realized that firing the partially completed Halo would destroy it as well as the Ark. He turned on the team in an instant. His initial attack killed Johnson, hurt Thel and threw him out of the door, then severely damaged John-117. However, the SPARTAN managed to take Johnson's M6 G/GNR and used it to destroy Guilty Spark. John then activated Halo.

After exiting the door, all of the Sentinels fired on turned on them like Guilty Spark had. They fought through Flood forces and every Sentinel left on the Halo. In an attempt to escape from certain doom, they mounted up on the abandoned Warthog left behind by Sergeant Johnson, and rode as fast as they could to the Forward Unto Dawn. They rode through a labyrinth of construction tunnels, collapsing platforms, and enemies, being shot at everywhere they went. The eventually made it to the Dawn just in time. Thel climbed to the bridge of the ship, and piloted it to safety while John struggled to hold on in the cargo bay of the vessel. They made it through the portal just as Halo fired.

Aftermath
This battle marked the end of the Flood threat. After Halo fired, all Flood and Sentinel forces as well as any surviving Covenant forces present on the Ark were destroyed. It is presumed that Installation 00 was destroyed as well, or at least heavily damaged after 04B "shook itself to pieces".

While Forward Unto Dawn entered the portal, the field collapsed, severing the ship in two. The bow, with Thel inside, made it all the way to the exit coordinates above Earth and crashed into the Southern Ocean. The stern section was less fortunate; John and Cortana were trapped in the wreckage as it drifted towards an unidentified planet.

List of appearances

 * Halo 3
 * Halo Legends
 * Origins