Battle of Trove

The Battle of the Flood-controlled Shield World was an engagement fought between the UNSC Marines of the, the Covenant, and the Flood on a Forerunner Shield World during the Human-Covenant War on February 23rd, 2531.

Background
The Flood-Controlled Shield World had been discovered by the Covenant years prior to the battle, but despite their reverse-engineering attempts, they had not been able to activate its most prized artifact, The Apex, which contained numerous Forerunner Ships. As the Human-Covenant War started, the Covenant hastened their search for a key to activate the ships, in order to exterminate the human race even faster. 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 First Battle of Arcadia, planning to use her to activate the ships' systems. The 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 planet's surface, along with a small force led by Forge. Using Elephants and Marine infantry, together with air support from Shortsword-class 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 team's Elephants and retreated back to the Firebase being constructed at the beacon site. UNSC forces also had 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 SPARTAN's and destroy the Gravemind.

Descent
After destroying the Proto-Gravemind, the Spirit of Fire's A.I 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 Foreunner 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 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 Gremlin Combat Support Vehicles, giving them a little longer. After evacuating Alpha Platoon and Bravo Platoon, the team had to escort Charlie 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
In the inner Dyson Sphere of the Shield World, the Spirit of Fire was immediately engaged by a Covenant Destroyer. 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 A.I, 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 a huge fleet of Forerunner ships. In their religious fervor, her guards were distracted and Anders used a Transporter pad to return to the surface, where she was rescued by Forge.

The UNSC forces cleared an area and established a Station. 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.

The Apex
To prevent the Covenant from gaining control of the ships, the crew devised a plan to use the Spirit's Shaw-Fujikawa Translight Engine to cause the miniature sun in the planet's center to go supernova, destroying the Shield World, though it meant that they would have no way to return home. After an attempt at airlifting the drive failed, Sergeant Forge used a Behemoth-class Troop Transport to tow the drive to the top of a ramped hill with a teleport to the Apex site's control center. The UNSC forces established two base sites, building up a large mechanized force with air support, and ascended a 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 SPARTAN-II Red Team to the Apex's control center with the Slipspace Drive. On the Apex's main platform, Forge, the Red Team and the Lieutenant prepared to load the slipspace drive into an elevator which led to the Shield World's artificial sun. Suddenly, The Arbiter, who was cloaked, killed the Lieutenant who was opening the door to the elevator. Forge released the locks holding the FTL Drive on to the truck, and ramped it at the Arbiter. A group of Sangheili Honor Guardsmen appeared from the other end of the platform, and charged at the SPARTANs Jerome-092, Douglas-042 and Alice-130, who held them off with relative ease. Meanwhile, Forge killed the Arbiter. After this, Forge decided to sacrifice himself in order to detonate the drive. The Spartans returned to the Spirit of Fire, while Forge ascended up into the sun.

Escape
Serina found that the exit 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 locks. Using tanks, Vultures, Carpet Bombing, Cryo Bombs, and orbital bombardment to destroy the Covenant and Flood bases, they successfully opened the doors.

The Spirit of Fire escaped the planet before Forge activated the reactor in the installation's star. Forge did not make it out alive.

As the sun slowly went supernova, the Spirit of Fire was caught in its increasing Gravity Well. Slingshotting 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.

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 cryo-storage. 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.