Battle of High Charity

"Rise, pack brothers! Cast down the Elites!"

- Tartarus

The Battle of High Charity was a large battle for the control of the Covenant capital world High Charity among the Covenant, the Covenant separatists, limited UNSC forces, and later, the Flood. The battle marked several significant events, including the start of the Great Schism, SPARTAN John-117's pursuit of the Prophet of Truth to Earth, and the Flood invasion and infestation of High Charity.

The fracturing of the Covenant
With the Jiralhanae, who directly competed with the Sangheili, slowly gaining the favor of the San 'Shyuum Hierarchs, it was only a matter of time before the latter were overthrown and open warfare began between the two parties. Recent failures of the Sangheili leading up to the battle, including the loss of Installation 04 and the assassination of the Prophet of Regret by the UNSC, damaged the reputation of the Sangheili and further empowered and emboldened the Jiralhanae. These events spurred the Changing of the Guard, giving the Jiralhanae the duty of protecting the Prophets - an honor traditionally held by the Sangheili, further damaged their reputation and position within the Covenant.

Battle of Installation 05
The Prophet of Regret's wayward mission to Earth brought High Charity, John-117 and the to Installation 05. The subsequent assassination of Regret by John-117 on November 2, 2552, shocked the entire Covenant ruling structure. The Sangheili-controlled fleet's attempt to kill John-117 from orbit had failed and instead threw him into the clutches of the Gravemind, located deep underneath the Library of Installation 05. With the Gravemind already plotting its way off of the Halo, this would set the tables for the invasion by both the Flood and the "Demon". It would be Tartarus, however, who put the final pieces of the puzzle into place—some of them inadvertently. After the Arbiter successfully acquired Installation 05's activation index from the Library, Tartarus attempted to execute him by firing a burst from his Fist of Rukt at the Arbiter and knocking him into the depths of the Library—and into the Gravemind's lair. Tartarus then took the Index and Commander Miranda Keyes and Sergeant Major Avery Johnson as prisoners back to High Charity where the Hierarchs waited.

Gravemind
With the index in the hands of the Covenant, and as ignorant as they might be to the true purpose of the Halos, they were fully intent on firing them - an act that would prove fatal to the Gravemind should it occur. As such, the Gravemind knew that it must not be activated, and for that he brought John-117 and the Arbiter together. After persuading the Arbiter of Halo's true power, he sent John-117 to High Charity and the Arbiter to the local installation's Control Room - the two most likely places for the Index to be. He then prepared to bring the other part of his plan into action - the invasion of High Charity.

Opening skirmish
"The Demon has infiltrated the Council Chamber?! Protect the Hierarchs! Seal the exits!"

- Tartarus commanding his Jiralhanae on loudspeakers.

By the time John-117 arrived at High Charity, the High Charity defense fleet was in chaos. Sangheili and Jiralhanae-controlled ships engaged one another amongst the vast number of ships protecting the city. In the Council Chamber, Truth, with Mercy next to him, was giving a speech to the Covenant acknowledging the release of the Flood and announcing Tartarus' successful acquisition of the "sacred icon". As Truth's speech drew to a close, John-117 was teleported into the room by the Gravemind, appearing right beside the Unggoy who was filming the speech. He acquired the Unggoy's Needler and aimed it at the Hierarchs, but the Jiralhanae protected the Prophets in order for them to escape.

Tartarus sent lances to secure the Council Chamber, but the Spartan prevailed. John-117 inserted Cortana into High Charity 's security systems so she could open the doors to the room. She then opted to remain in the system as she felt it would provide her the greatest opportunity to aid him. With the Index clearly in the possession of the Prophet of Truth, the Spartan chased after the fleeing Prophet. Shortly after beginning his hunt, Cortana noted that there were Marine transponders near the Master Chief's position. After raiding the prisons, five Marines joined the Spartan in his hunt for the Prophet.

The Great Schism begins
"The Elites have failed to protect the Prophets, and in doing so, have put all our lives at risk. Let no warrior forget his oath, "Thou, in faith, shall keep us safe, whilst we find the Path". With my blessing, the Brutes now lead our fleets! They ask for your allegiance, and you shall give it."

- Prophet of Truth making announcements throughout the city

Soon thereafter the Marines were rescued by the Master Chief and the Prophet of Truth declared that the Jiralhanae were now in charge of all Covenant fleets. The Jiralhanae, under the support of Kig-Yar and Yanme'e, then instigate a genocide of the Sangheili, as secretly ordered by Truth. The Sangheili warriors retaliated with the assistance of Mgalekgolo and even Sangheili Councilors while Unggoy pledged their allegiances to both sides. As John-117 and his marines followed Truth, they bore first-hand witness to the fracturing of the Covenant, sometimes opting to watch as the two sides fought rather than becoming directly involved. The Jiralhanae focused on attacking Sangheili in the towers of the city, then spread out to the lower levels. The Sangheili that survived the initial betrayal retreated from the Valleys of Tears and Hanging Gardens to the Mausoleum of the Arbiter to make a last stand, supported by many Mgalekgolo and Unggoy. The causeway leading to the Mausoleum became a battlefield choked with dead from both sides. However, the Jiralhanae were eventually able to push through, and fighting spread to the central chamber of the Mausoleum itself. The arrival of John-117 and the surviving Marines led to elimination on both sides.

Invasion of the Flood
"Slipspace rupture. It's In Amber Clad! Hailing... No response. She's crashed into another tower ahead of our position. I'll keep trying to make contact, but I'm not registering any human vital signs."

- Cortana to John-117 after witnessing the frigate flying over them.

Sometime later, entered High Charity via Slipspace, flying across the city before crashing into a tower. Cortana tried to contact the ship but registered no life signs on board, as the frigate had been captured by the Flood and it was they who had flown it in. The various short-range crafts it possessed launched and spread the Flood infection throughout the city. D77-TC Pelicans carrying Flood forms flew over the city, further escalating the infection.

"The Great Journey awaits no one, brother...not even you."

- Prophet of Truth talking to Mercy as the latter suffers from a Flood infection form.

Shortly after the battle in the Mausoleum, Truth made it to his escape Phantom and handed the Index over to Tartarus to incept the "Great Journey". Tartarus prepared to take the Index along with UNSC prisoners Commander Keyes and Sergeant Major Johnson to Installation 05 to activate the Halo. Before they could leave, however, Flood infection forms attacked them. Tartarus and Jiralhanae Honor Guards tried to defend the Prophets of Truth and Mercy, but one of the infection forms got through their screen and landed on Mercy. When Tartarus tried to remove the infection form, Truth ordered him to let the Prophet die so Truth himself could be the sole Hierarch ruling the Covenant. A surprised Tartarus proceeded down to the surface with Commander Keyes.

Closing
"This crisis will not be the end of us. It is but one last hurdle before the Journey and salvation!"

- Prophet of Truth as he retreats to his Dreadnought.

By the time John-117 had reached the Prophet of Mercy, the Prophet was nearly dead and the Marines he had rescued had similarly fallen. In his interrogation of the Prophet, he learned that the Prophet of Truth was fleeing towards Earth. Cortana determined that Truth was heading towards the Forerunner Dreadnought which stood in the middle of the city. With the Arbiter still on Installation 05 and Cortana stating that she could detonate In Amber Clad ' s reactors if it was needed to destroy the Halo installation, John-117 proceeded to follow Truth and attempted to board his ship before it left. However, Cortana chose that she could not trust the fail-safe detonation of In Amber Clad to any copy of herself and had to remain behind. With Cortana stalling the launch of the Forerunner Dreadnought, John-117 barely made to the Dreadnought in time through the conduit. Before he left, the Chief promised to come back for Cortana.

Since the Forerunner Dreadnought served as the power source to High Charity, most of the lighting shut down as a result of the Dreadnought leaving the city's power grid. The large body count from the battle became a source of creating more Flood forms, which tilted the battle in their favor as Flood growth pods began growing on surfaces and the city's atmosphere became polluted by Flood spores. As Flood forms swarmed the Tower District, the Covenant loyalists led by the Jiralhanae was overrun after the separatists were wiped out. The Flood carrier forms spread the Flood infection to certain ships in the fleet, bringing both Covenant loyalists and the Sangheili-led separatists to the attention of a need to contain the infection. Consequently, the Sangheili fleet set up a quarantine perimeter around High Charity as well as Installation 05 to prevent any Flood-controlled ship from leaving the system.

The Great Schism
The battle became the first major battle of the Great Schism. Warships around High Charity continued to fight well after the battle on the surface of High Charity itself was over. That said, the fact that neither side was able to acquire control of High Charity likely limited any major gains that were to be had.

Tartarus and the Index
Tartarus eventually arrived to the Control Room with Miranda Keyes and began the firing sequence for Installation 05. However, the Chieftain fell to the Arbiter and the firing sequence was aborted, putting all remaining Halo installations into standby mode, readying them for a final activation from Installation 00.

The Prophet of Truth and John-117
The Prophet of Truth and John-117 eventually reached Earth and participate in the Battle of Earth. Upon its arrival, Lord Hood ordered the ship to be destroyed, but John-117 identified that he was aboard the ship and wanted to finish the fight. The Spartan failed to assassinate Truth aboard the ship, which led to his breakout and eventual landfall to Earth's surface.

High Charity and Cortana
The Flood eventually gained full control of High Charity and the Gravemind took up residence in the fortress, turning the city into a massive Flood hive. Cortana, who was stranded in High Charity's computer systems, was questioned by the Gravemind who interrogated and tortured her. This drove her to the point of rampancy, but she managed to send a message to Earth and hold onto an important secret. Although the Forerunner Dreadnought decoupled from the city, the Flood managed to transport the High Charity to Installation 00 via slipspace during the Battle of the Citadel by using the city's backup reactors. The city crashed on to the surface, spreading Flood infection and adding chaos to the final battle of the Human-Covenant War. After Truth's death, John 117 returned to the city to rescue Cortana, destroying the city by overloading its reactors, which caused it to go critical and detonate.

List of appearances

 * Halo 2
 * Halo: Ghosts of Onyx