Battle of Installation 04

The Battle of Installation 04 was the name given to a series of skirmishes between the forces of the UNSC and the Covenant.

In the latter part of the battle, the UNSC and Covenant were joined in battle by the Forerunner Sentinels and Flood.

Fleeing Pillar of Autumn
Following the disastrous defeat at Reach, the UNSC Pillar of Autumn made a blind slipspace jump, from where they would then make their way to Earth. The Pillar of Autumn was followed and, upon arriving in orbit of the planet Threshold, were intercepted by the pursuing Covenant vessels.

As the Covenant began boarding Pillar of Autumn, the vessel managed to destroy four of the Covenant vessels and force one, Truth and Reconciliation to retreat for repairs. As the boarding of Pillar of Autumn continued, Thom Shephard was forced to release Master Chief Petty Officer John-117 from his Cryo-chamber but was later killed by a conduit explosion.

The Master Chief then proceeded to the bridge of Pillar of Autumn where he was joined with the shipboard AI Cortana, he then evacuated to the recently discovered Installation 04 along with most of Pillar of Autumn's crew.

Upon arrival on the ring, Captain Jacob Keyes was captured by the Covenant. The Master Chief managed to rescue a number of Marines before executing a successful rescue operation aboard Truth and Reconciliation.

September 20, 2552
The following day, the crew of Pillar of Autumn launched an attack on the Silent Cartographer island, in their attempt to uncover the purpose of the ring. Fighting their way through the heavily defended Covenant positions, the Master Chief and a handful of Marines discovered the location of Alpha-Halo's Control Room.

Making their way to the Control Room, the UNSC forces encountered the Forerunner construct 343 Guilty Spark, who served as guardian over the ring. After much more fighting, Master Chief entered the Control Room and discovered that the weapons cache that Captain Keyes was looking for was actually a Forerunner base, and that Halo wasn’t a Covenant construct.

Master Chief and 343 Guilty Spark left the Control Room for the swampy areas of the installation. After a short time, the "weapons cache" Keye was looking for reveals itself in the form of the Flood. The Chief fought his way into Alpha Halo's main Flood containment facility in his mission to stop the newly released Flood.

September 21, 2552
343 Guilty Spark then transported the Master Chief to the Library of Installation 04, where he was tasked with locating the Activation Index. After succeeding, Master Chief prepared to active the ring, but was stopped by Cortana, who, after a brief argument with 343 Guilty Spark, revealed the true function of the ring to John-117; 343 Guilty Spark delightfully confirmed Cortana's belief.

Master Chief, deciding not to activate the ring, makes an enemy of 343 Guilty Spark and has the Sentinels sent against him. The Master Chief destroyed the three pulse generators that magnify the signal sent out by Halo, disabling the facility for the time being. The Chief was then teleported with Cortana to a Covenant cruiser, where Jacob Keyes was being held. During a second rescue attempt the Chief was too late to rescue Keyes, who had been taken over by the Flood and transformed into a Brain form. The Chief took the neural interface from Keyes, fought his way back through the ship, to the landing bay where he commandered a Banshee; he then set a course for the Pillar of Autumn, with the intention of destroying the vessel.

September 22, 2552
Crashing aboard Pillar of Autumn, made their way to the bridge of the vessel and activate the self-destruct sequences, only to have 343 Guilty Spark cancel the order. Realising that only a manual self-destruct would work, the Chief made his way to the rear of the ship, using a Warthog to traverse the spine of the ship.

Finally arriving, the Chief destroyed the Pillar of Autumn's fusion reactors which initiates a chain-reaction of explosions. The Chief escaped the destruction of the ring aboard a C709 Longsword-class Inteceptor. The Master Chief and Cortana, onboard the Longsword in the debris field of the destroyed Halo, found a Pelican containing Sgt. Johnson, Sgt. Stacker, Lieutenant Haverson, Warrant Officer Polaski, Corporal Locklear, and a set of cryotubes containing Spartan-058, Linda.

UNSC

 * UNSC Pillar of Autumn
 * Captain Jacob Keyes
 * SPARTAN-II, Master Chief Petty Officer John-117
 * SPARTAN-I, Sergeant Avery Johnson
 * Crew of the UNSC Pillar of Autumn

Covenant

 * Fleet of Particular Justice
 * The Supreme Commander of the Fleet of Particular Justice

Forerunner Constructs

 * 343 Guilty Spark
 * Hundreds of Sentinels

Flood

 * At least 1 Brain Form
 * Thousands of Combat Forms
 * Hundreds of Thousands of Infection Forms

Related Articles

 * Human-Covenant War
 * Installation 04
 * Raid on the Truth and Reconciliation
 * Battle of the Silent Cartographer
 * Battle of Installation 05