Truth's fleet

In the final months of the Human-Covenant War, the High Prophet of Truth had a massive fleet under his personal command. Originally composed of over five hundred capital ships, it was initially one of the largest known Covenant fleets although the fleet suffered tremendous losses when its command-and-control station, Unyielding Hierophant, exploded. After rebuilding the fleet for some time and aware of the Prophet of Regret's assault on Earth, Truth sent it to Earth, where it was dispatched at Mombasa to excavate the Portal at Voi that lead the Ark and secure the area for Truth's arrival by his loyal fleet. On November 17, the fleet was joined by remnants of the Covenant forces loyal to the Prophets from the High Charity defensive fleet and Truth himself. Later, the fleet journeyed through the Portal to the Ark, where it met its end.

Formation
Following the Fall of Reach, the Prophet of Truth discovered the location of the human homeworld and started assembling a massive fleet of over five hundred warships for the planned invasion of Earth. Ships scattered around the galaxy were ordered to regroup, including one group of ships that was to jump to the Lambda Serpentis system, to gather tritium gas for their reactors and then the Hawking system to meet with three dozen carriers and effect a transfer of Seraph fighters. Finally, the fleet would be summoned to the command-and-control station, Unyielding Hierophant which was holding position in Tau Ceti system in September, 2552. When a sufficient amount of ships were gathered, the fleet would then make a collective jump straight to Earth.

Due to Truth's devious plans for the Covenant, this fleet was commanded exclusively by the Jiralhanae and featured only few Sangheili in its ranks; an arrangement unheard of in the Covenant before the Great Schism. For similar reasons, Truth kept the existence of this fleet, and the fact he had discovered humanity's homeworld, secret even from his fellow Hierarchs. This would make it a simple matter to turn the fleet against the Sangheili once the humans were wiped out. This plan had more immediate advantages as well; leaving the Sangheili to scour Earth in search of the most sacred Forerunner artifact in existence, the mammoth structure and portal generator that served as the gateway to the Ark, would have placed Truth's plan upon the shoulders of a species he had already decided to cast aside.

However, Truth's plan was slowed down when a small group of human survivors from Reach and Installation 04 discovered the fleet, leading to the destruction of the Unyielding Hierophant at the hands of a team of SPARTAN-IIs. Only a dozen ships survived the station's explosion, though they were left heavily damaged and limped back to High Charity. For a moment the imminent assault on Earth had been postponed. Following the loss of Unyielding Hierophant, in High Charity the Chieftain of the Jiralhanae Tartarus arrived at the Sanctum of the Hierarchs where Truth waited within.

Once informed on the destruction of his armada, while disturbed by the disaster, Truth otherwise regarded it as a minor setback, and told Tartarus to have the surviving ships rendezvous at their designated coordinates. He also ordered the reward and secret execution of the remaining pilots from Operation: FIRST STRIKE, so as not to cause panic in the Covenant by stories of how the Demons had obliterated an entire fleet of hundreds of warships. Knowledge of the Unyielding Hierophant's ultimate goal, and its eventual destruction, were eliminated by the Prophet of Truth to keep his plans as a secret to the rest of the Covenant.

After the Unyielding Hierophant was destroyed, the Prophet of Regret, completely oblivious of Truth's plan, discovered the location of the gateway to the Ark by via a Forerunner Luminary that was found on Meridian at the end of 3-years-long siege on the planet in 2551; coincidentally, this structure was located on a planet known as "Erde-Tyrenne" by the Forerunner, which was in fact the human's homeworld, Earth. Unaware of the human presence, Regret led a detachment of fifteen ships to Earth. While he learned of the human presence upon arrival on October 20, he was so blinded by his religious fervor he ignored Earth's orbital defenses and jumped to the planet's surface, immediately deploying troops to the African city of Mombasa in search of the Forerunner artifact, while his ships fought the UNSC Home Fleet, including the Fifth Fleet and the Seventh Fleet, in orbit.

Battle of Mombasa
Immediately after the Prophet of Truth learned of Regret's departure to Earth and rebuilding his fleet as a large support and excavation fleet for the Portal to the Ark, he sent his fleet after him and initialed his plan to replace the Sangheili with the Jiralhanae as the Covenant's primary warriors while doubting the reliability and loyalty of the Sangheili earlier. These forces of Truth's renewed fleet led by the Jiralhanae was both archaeological and military. While Truth's fleet was on its way after Regret's carrier was forced to retreat as UNSC forces retook the city, the remaining Covenant forces, now without a leader, continued to engage the Home Fleet in space. Shortly after, the Jiralhanae that were left behind by Regret were given orders to eliminate the Sangheili still in command of what was left of Regret's fleet and kill any remaining Sangheili troops still stationed on or above the planet; an order they would willingly obey.

As ordered by Truth, the Jiralhanae assumed the total command of the remainder of cruisers of Regret's Fleet of Sacred Consecration, including the Pious Inquisitor, battling UNSC forces above and within New Mombasa. They as well aggressively began occupying the city with significant infantry, until Truth's reinforcements arrived to ensure that the arrival of the Prophet to the Portal nearly a month later was to be fully secured by his true loyalists as the Covenant forces on the city was needed to be led by the Jiralhanae and not the Sangheili to avoid his aspirations upon the shoulders of a species he had planned to expel from the Covenant and eliminate them.

Later, the cruisers were gathered over the industrial center and started excavating the Forerunner structure by glassing the planet's surface around it, including Mombasa, starting from the crater created by the in-atmosphere slipspace jump of Regret's ship. Eventually the next day on October 21, the Prophet of Truth's fleet arrived to join Regret's fleet remnants for excavation of the excession to the Ark while more and more other Covenant reinforcements later arrived and launched a large full-scale assault on the planet. While the majority of Covenant forces that were under Truth's command, including most of his fleet, were preoccupied and focusing their primary objective for the excavation of the portal as the largest and most organized Covenant stronghold on the planet, only a handful of vessels of Truth's fleet and its deployed forces attacked the UNSC forces, including those at the outskirts of Mombasa during the seven-day-long second battle of the city. However, some of these forces were disorganized and sometimes less effective against the UNSC.

Further engagements
In November 2552 after the beginning of the Great Schism when the Sangheili were thrown out by the Covenant now solely led by the Prophet of Truth and its Jiralhanae loyalists, the Flood overwhelmed High Charity and the remaining Covenant reorganized in an attempt to make a final push offensive on Earth. By the time the surviving ships and fleets of the High Charity defense fleet controlled by the San'Shyuum and Jiralhanae, including the Second Fleet of Homogeneous Clarity, managed to follow the Prophet of Truth and his Dreadnought to Earth, where they would join the Covenant forces that had arrived earlier. While the Dreadnought, along with a Covenant escorting fleet, traveled through the system for a period of nine days as it was delayed by the presence of the Spartan-II Master Chief Petty Officer John-117 before eventually jumping to Earth on November 17, a massive Covenant loyalist armada led by the Prophet of Truth arrived in the Sol system. By this point, the UNSC was hardly faced with impossible odds with no hope in sight against the full might of Covenant forces on Earth as they began to dramatically increase and mostly focus their forces on the planet following the UNSC's defeat on Mars after the Battle of Mare Erythraeum. However, Colonel James Ackerson's work in the siege on Mars helped buy UNSC ground forces on Earth precious time.

The final Covenant fleet breached Lunar perimeter and then battled the horribly-outnumbered and outgunned UNSC Home Fleet that was already weakened by waves of Covenant fleets over Earth. Shortly after, the Dreadnought jumped to Earth where it was later surrounded by the massive space battle between the opposing fleets in high Earth orbit. Ultimately, the UNSC defending orbital forces was unsuccessful as too much of the UNSC fleet, including many smaller remaining fleets, and defense forces despite having strong defense was completely obliterated by the overwhelming Covenant fleet but it is likely that countless Covenant vessels, especially the capital ships, was in return destroyed, mainly because of the planet's unusually strong defense, including hundreds of orbital defense platforms equipped with "Super" MAC guns. Soon after the remnants of the Covenant fleet move in and began to massively bombard Earth, destroying an extreme number of Earth population, including the most of scattered and remaining UNSC resistance forces.

However, before the planet could be completely glassed and fell with relative ease to the might of the unparralled Covenant invaders like Reach with an all but achieved and inevitable Covenant victory, the act of self-sacrifice of James Ackerson and that of his civilian brother, Ruwan, managed to slow down Covenant occupation of Earth after the destruction of the Harbinger of Piety, hence the death of one of Covenant Ministers, and the fact that a supposed Forerunner artifact, known as the Key of Osanalan, was not real at the end of the Battle of Cleveland in North America. As a result, the Martian valiant defense forces despite being defeated by the Jiralhanae-led Fleet of Furious Redemption, which sympathized Truth's forces, were credited for delaying the Covenant from pressing their siege on Earth.

Upon Truth's arrival on Earth the Dreadnought landed directly on the nearly uncovered Forerunner Portal at Voi that lead to the Ark on the East Africa, allowing his fleet to cluster around the structure and set up a defensive perimeter. After the Master Chief joined up with UNSC forces, he spearheaded an effort that pushed the fleet's ground forces further towards their innermost stronghold – the Forerunner portal generator. However, they were too late to prevent Truth from activating the Forerunner structure. After the Prophet of Truth activated the Portal, its fleet under his command went through the slipspace rift to the Ark, a massive Forerunner installation outside the Milky Way Galaxy. Soon after this the Flood-controlled battlecruiser appeared and crashed into the city, delaying the UNSC's attempt to pursue the loyalist fleet and forcing them to blow up the ship.

Battle of Installation 00
On December 11, the fleet used this time to deploy ground forces to the Ark, while Truth and his bodyguard of Jiralhanae moved to the Citadel to activate the Halo rings.

After the humans and Sangheili contained the Flood on Earth, a joint UNSC-Sangheili effort, consisting of the Battle Group Victory, and a battle group of the Seperatist Fleet of Retribution, spearheaded by the assault carrier, Shadow of Intent, managed to follow the Covenant ships a few hours after their initial retreat through the portal. Upon arriving above the Ark on December 11, the Jiralhanae fleet engaged the Fleet of Retribution, backed up by the UNSC frigates. While Truth's fleet outnumbered the UNSC-Sangheili fleet three to one, the Sangheili's tactics proved superior to that of the Jiralhanae, eventually obliterating the entirety of the loyalist fleet except at least one heavy cruiser that abandoned the other Covanant forces to their doom earlier. Together with the utter defeat of the Jiralhanae-led forces on the Ark itself during the conflict on the installation and Truth's eventual death at the hands of the Arbiter Thel 'Vadam, this signalled the final and pyrrhic UNSC-Sangheili victory over the Covenant and the end of the 27-years-long Human-Covenant War.

As of April 2559, the wreckage of one of Truth's cruisers remained to orbit the Installation 00.

Composition
As of late 2552, at least two known fleets, both the over-500-ships-strong combined armada and the latter rebuilt excavation fleet replacement, that were controlled by the Prophet of Truth were gathered as the Prophet's plan for the assault on Earth after secretly discovering the planet in aftermath of the Fall of Reach, particularly the occupation of the portal to the Ark at East Africa. All exclusively led by the Jiralhanae who showed a great ferocity and an unquestioning loyalty to the Prophets even more than the Sangheili who were formerly the top of the Covenant military hierarchy until the Great Schism, this was also made as a plan to replace Sangheili by Jiralhanae as the main military leaders as Truth was obsessed with the Great Journey and the stability of the Covenant Empire.

Although only few forces of the second and excavation fleet engaged the UNSC forces on Earth while most of Prophet of Truth's excavation fleet remained preoccupied with the Portal, numerous other Covenant forces, fleets and vessels were deployed during the Covenant assault on Earth and the rest of the Sol system, such as Mount Erebus, the Yucatan Peninsula and Havana, Cuba, Luna, and Mars with a number of Covenant warships that engaged 3 UNSC fleets of the Home Fleet over Earth on November 3. However, it is unknown if they were part of the forces led by the Prophet of Truth and his Jiralhanae loyalists as they were maybe led independently by other Covenant leaders but less organized than Truth's forces, possibly even led by Sangheili commanders until their betrayal at the time of the Great Schism when the Jiralhanae would assume the total command of Covenant forces in the Sol system, including the Fleet of Furious Redemption, and sympathized the Prophet of Truth and his loyal forces.

Forerunner keyship

 * Anodyne Spirit – Flagship of the Prophet of Truth and his fleet after the Fall of High Charity, remains intact as of 2559.

ORS-class heavy cruisers

 * Gathering of Praise – Commanded by Hekabe, participated in the Battle for Earth and survived the Battle of Installation 00. Later named as Foebane and destroyed during the Carrow Conflict.

Covenant frigates

 * Twilight Compunction – Commanded by Gargantum, participated in the Battle of Installation 05 and later in the Battle for Earth. Destroyed during the Battle of Installation 00.

Allied fleets

 * Fleet of Furious Redemption – Status unknown
 * Jiralhanae-controlled High Charity defense fleet
 * Jiralhanae-controlled Second Fleet of Homogeneous Clarity

List of appearances

 * Halo: First Strike
 * Halo 2
 * Halo: Uprising
 * Halo 3
 * Halo 3: ODST
 * Halo 2: Anniversary
 * Halo Mythos
 * Halo Wars 2