Battle of Trove

The Battle of the Etran Harborage was an engagement fought between the crew of the, the Covenant, the Flood, and Forerunner forces on the Forerunner shield world known as the Etran Harborage during the Human-Covenant War from February 23 to 25, 2531.

Background
The Etran Harborage or "Trove" had been discovered by the Covenant some time prior to the battle, but despite their reverse-engineering attempts, they had not been able to activate the shield world's most prized artifact: the Apex Site, an installation which contained numerous Forerunner s. With the Human-Covenant War ongoing, the Covenant started their search for a key to activate the Forerunner ships in order to bring a swifter end to the human race. After seeing Ellen Anders activate a Forerunner structure on Harvest, the Covenant discovered that they could use a human to activate the Apex installation.

Arbiter Ripa 'Moramee captured Professor Anders after the Battle of Arcadia, planning to use her to activate the Forerunner dreadnoughts' systems. The UNSC Spirit of Fire pursued the Covenant to the shield world without reinforcements to rescue Anders. Upon entering the system they followed Anders' transponder signal the best that they could. Captain Cutter launched several Marine teams, as well as Sergeant John Forge to begin surface operations to locate Professor Anders.

Initial actions
Recon Teams Echo and India deployed on the shield world's surface, along with a small force led by Forge. Using Elephants and Marine infantry, together with air support from Shortsword bombers and help from SPARTAN Red Team, Forge's force cleared an area of Jiralhanae around a beacon, awaiting the arrival of reinforcements and the Recon Teams.

First encounter
Shortly after this, however, the force received an ominous message from Echo Team, stating that they were under attack from "things," before dropping out of contact. India Team sent a similar message before dropping out of contact.

Forge's team and the Spartans moved to investigate, encountering the Flood for the first time, including dozens of infection forms that resulted in a large number of Marines being lost. However, they successfully recovered both teams' Elephants and retreated back to the Firebase being constructed at the beacon site. UNSC forces began to have problems with air transport, as the exterior surface's atmosphere was thick with dust, which caused the engines on Pelican dropships to fail within three flights.

Red Team discovered that a proto-Gravemind was coordinating the Flood forces and was also jamming Ander's transponder signal. However, before they could destroy the Gravemind, their Warthog was overturned and they had to be rescued by Forge's Marines. After contending with Flood swarms and Thrasher Forms, the Marines were able to rescue the Spartans and destroy the proto-Gravemind.

Descent
After destroying the proto-Gravemind, the Spirit of Fire's AI Serina located Anders' signal, which was apparently in the middle of an ocean. While the Spirit was hovering over the sea, the doors of a huge submerged entry into the planet opened and several Forerunner Sentinels flew out. The Spirit of Fire became locked into a powerful docking mechanism and inevitably began a controlled 'fall' into the rift. The remaining UNSC forces on the Shield World's surface, composed of Alpha Platoon, Bravo Platoon, and Charlie Platoon, had less than twenty minutes to fight their way past hundreds of Flood forms before being airlifted back to the Spirit of Fire. Flood swarms made air support almost useless, forcing the Marines to use large numbers of Wolverines to clear the air before tanks and infantry could clear landing zones of Flood growths. They managed to slow down the Spirit of Fire's descent by disabling Forerunner pylon towers powering the docking system with XRP12 Gremlins, giving them a little longer. After evacuating the first two platoons, the team had to escort the final platoon back to the firebase for extraction after their Pelican was forced to abort its run. After extracting all UNSC forces, the firebase was abandoned to the Flood and the Spirit of Fire began her descent.

Fighting their way down through a service conduit inside the Shield World, the Spirit of Fire was attacked by even more Flood forms. Flood growths began to sprout on the ship's hull, and Marines and aircraft were forced to fight on the hull of the ship to remove the Flood forms. Furthermore, Sentinels attacked the Flood, and while they initially provided some support to the UNSC, after passing through the first decontamination ring, the Sentinels identified them as possible infection vectors and relabeled them as targets. The UNSC forces managed to clear the hull of growths, removing the Flood and thus allowing the Sentinels to withdraw. After this, the Spirit of Fire accelerated out of the tunnel, and emerged into the interior of the Shield World.

Interior
"The Ancients have granted us the power to doom your race. Let the deconstruction of our gifts begin! The majesty of our new fleet will be unparalleled!"

- The Arbiter to Anders.

In the inner Dyson sphere of the Shield World, the Spirit of Fire immediately entered a collision course with the Covenant destroyer Proclamation's Tithe. Despite hard course corrections, the two ships impacted, with a large section of the Spirit being violently sheared off. The collision also destroyed half of the Spirit's complement of D20 Herons. Dozens of Marines, vehicles, and aircraft were deployed onto the Spirit's hull to fend off boarding parties who were trying to prevent technicians in Cyclops exoskeletons from repairing the ship's power core, while at the same time the ship was raked by plasma fire. Escaping from the destroyer, the Spirit's AI, Serina, detected Anders' signal. Sergeant Forge, along with other forces, were deployed to the signal's apparent source on the Shield World's inner surface.

Imprisoned in the Apex, Anders was forced by the Arbiter to activate the ancient artifact, powering up its fleet of s. In their religious fervor, her guards were distracted and Anders used a teleporter to return to the surface, where she was rescued by Forge. Anders was then evacuated back to the Spirit, while Sergeant Forge and Spartan Red Team proceeded to lock the area down, for a safe place to the Spirit to put down. Anders theorized that they would have to capture four base sites to begin an effective resistance. Through the use of armor, air support, and a Scarab captured by a Spartan, the UNSC captured the bases and prepared to attack the Apex itself.

On the Spirit of Fire, Anders devised a plan to stop the Covenant from using the Forerunner ships. The UNSC forces would have to sacrifice the Spirit's Shaw-Fujikawa Translight Engine to create an explosion so powerful it would collapse the miniature artificial star inside the Shield World, completely obliterating the installation, though it meant that they would have no way to return home. To accomplish this, they would need to assault the Apex Site and use an elevator on the main platform, to take the slipspace drive right into the star.

Assault on the Apex
When the UNSC forces had secured the area, the Spirit put down close to the surface, to deliver Slipspace drive to the ground. It was attached to two Pelicans, which were to be used to transport it to the Apex main platform. On their way however, they were shot down, just under a towering hill comprised of a series of ramps, on top of which there was a teleporter which led to the Apex's control center.

After an attempt at airlifting the drive failed, the mission was changed into a ground operation, with the intent of using an Elephant to tow the reactor to the teleporter on the top of the hill, which was full of Covenant and Flood forces. The UNSC established a firebase on the bottom of the hill, and gradually ascended the towering hill up to the Apex Base Site, meeting determined resistance from the Covenant. They eventually reached a teleporter that took Sergeant John Forge, a Marine lieutenant, and Red Team to the Apex's control center with the slipspace drive.

Upon arriving at the Apex Site's control center, the lieutenant, Forge and the Red Team proceeded with the mission. The lieutenant went to open the door of the elevator, Forge started to unload the reactor from its transport, while the Red Team guarded them. However, the Arbiter, who had previously been cloaked, appeared and killed the lieutenant just after the latter had activated the lift to the inner star. Simultaneously, multiple Sangheili warriors emerged from cloaking from the other end of the platform and charged the Spartans. Forge decided to take on the Arbiter himself, while the Red Team would hold off the Elites.

Forge released the locks holding the FTL drive on to the trailer, causing it to slide at the Arbiter. The Spartans engaged the Honor Guards in frantic and acrobatic close combat, dispatching them with ease. The Arbiter was gaining the upper hand in the duel with Forge, but the sergeant managed to take advantage of his opponent's hubris, wounding him with a combat knife and delivering a killing blow to the Arbiter with his own energy sword.

After the duel, the Arbiter's body was pushed off the platform, and the reactor was loaded onto the elevator. The reactor had already started overheating and could no longer be detonated remotely, leaving manual detonation as the only option. Jerome-092 offered to activate the reactor, sacrificing himself. Forge declined, saying that the UNSC would need every last Spartan left in the fight. Jerome agreed, commenting on the honor of serving with Forge. Forge began his ascent to the star, while the Red Team reported back to the Spirit of Fire.

Escape


The UNSC forces located one of the shield world's exit portals, but Serina found that the portal had been sealed off. Red Team and groups of Marines had to deal with massive Covenant and Flood resistance before they could disengage the door interlocks. Using tanks, Vultures, carpet bombing, cryo bombs, and orbital bombardment to destroy the Covenant and Flood bases, they successfully opened the doors.

As the sun slowly went supernova, the Spirit of Fire was caught in its increasing gravity well. By performing a gravitational slingshot maneuver around the sun, the Spirit was able to break away from the gravity well and escape through the portal, and far enough from the Shield World not to be caught in the supernova's blast radius. Moments after the Spirit of Fire escaped from the planet, it exploded, destroying Etran Harborage and all Covenant and Flood forces upon its surface.

Aftermath
With no ability to enter Slipstream space, and the journey back to UNSC space likely to take years, if not decades, the Spirit of Fire's crew went into cryostasis. The UNSC Office of Naval Intelligence declared the Spirit and crew to be missing in action. In 2534, the Spirit of Fire was declared to be "lost with all hands" by the UNSC. The reason for this change was kept top secret. A memorial service was held for the people aboard the vessel, but many of the crew's family members chose not to attend, holding out hope that their loved ones are still alive. Various theories circulated throughout the UNSC as to the ship's actual fate, ranging from being lost during a covert mission for ONI, destroyed in orbit over Arcadia, defecting to Insurrectionist forces, or being stranded in space. When Mary Cutter, wife of Captain James Cutter, was asked about the defection theory, she physically assaulted the reporter. The ship would not make contact with the outside world until 2559, when it was unexpectedly transported to Installation 00.

The Assembly, having intercepted transmissions from the Covenant battle network, noted the presence of the Flood as a "third variable". Due to the third participant being a terrifying opponent to the Covenant, the Assembly Minority suggested the possibility of forming an association - even a union - with it. However, due to the risks involved, the Assembly chose not to attempt contact with the Flood.

In early 2557, nearly twenty-six years after the shield world's destruction, the Ace of Spades, a salvager vessel captained by Sergeant John Forge's daughter Rion Forge, visited the debris field and recovered a fragment of the shield world's custodian AI. Several months later, ONI conducted a mission within its debris field to search for evidence of the Spirit of Fire.

Ships and vehicles
UNSC
 * Victor 397
 * Victor 397

Covenant
 * Proclamation's Tithe

Units
UNSC
 * Alpha Platoon
 * Bravo Platoon
 * Charlie Platoon
 * Recon Team Echo
 * Recon Team India
 * Red Team

Personnel
UNSC Covenant
 * Captain James Gregory Cutter
 * Sergeant John Forge
 * Douglas-042
 * Jerome-092
 * Alice-130
 * O'Neil
 * Papadakis
 * Prophet of Regret
 * Arbiter Ripa 'Moramee

List of appearances

 * Halo Wars
 * Halo: Reach
 * Data pads
 * Halo Mythos
 * Halo: Tales from Slipspace
 * Something Has Happened
 * Halo: Smoke and Shadow
 * Halo Wars 2