Labyrinth Glyph Icon
Help This article, Mandorla (Planet), is currently under active construction.
40px-Terminal.png This article, Mandorla (Planet), was written by Specops306 and Matt-256. Please do not edit this fiction without the writers' permission.
UNSC WARNING: This document, Mandorla (Planet), is property of the UNSC and is Classified [NOVEMBER BLACK], protected under Office of Naval Intelligence Security Protocol 1A. Disclosure of its contents to, or access or alteration by, personnel with a clearance level lower than GAMMA THREE is an offense punishable by court(s) martial and imprisonment or execution for treasonous acts. Failure to disclose confirmed or suspected breaches of security will be treated as complicity, and is punishable by dishonourable discharge and/or imprisonment.
Lieutenant Commander Michael Pomare, Office of Naval Intelligence, UNSCDF Navy
ONI Seal 1
Just Space by JoeJesus
General Information




Orbital Characteristics
Physical Characteristics

Discovered in late 2552, Mandorla is one of a handful of worlds known to belong to the mysterious Labyrinth Array, though it differs from other known Labyrinths, such as Minorca and Ares, in that it shares traits with Shield Worlds. The external surface of Mandorla is a habitable but otherwise uninteresting - the real machinery is contained within the inner surface of the planet. Mandorla would be the site of combat between offworld forces three times; the Mandorla Campaign of 2552-2553, activation by the Governors of Contrition, and then finally after the arrival of a small Sovereign force.



During the three-hundred-year long Forerunner-Flood War, many strategies were tried and failed to prevent the fall of sentient life before the tide of Flood advance. As a last resort, the Halo Array was constructed, samples of sentient life was recovered, indexed, and archived, the array was activated, and these indexed species were returned to their homeworlds. The Forerunners performed their task diligently and with careful attention to detail - the reintroduction was carried out by their machines, with no less meticulous care. Animal populations recovered. The histories of the few cultures that had survived were purged of all traces of Forerunner interference. Artefacts were buried or destroyed. The Forerunners intended their charges to have a free reign, hoping to avoid the technological stagnation they had unintentionally fostered through their rigid enforcement of the Mantle of Guardianship.

Mandorla, however, is a part of another array of vast, world-sized artefacts - the Labyrinth Array. While other worlds have been hinted at in sacred texts, or described in detail in semi-heretical documents by rogue historians, Mandorla itself is a mystery. It was probably built by a vast fleet of Sentinel constructs during the late stages of the war, as the Forerunners had begun construction of the Halo Array. The designer of the Labyrinth Array, a figure known only as The Architect, constructed these worlds for his own purposes, separate from the conventional Forerunner chain of command. Mandorla itself borrows heavily from Shield Worlds, designed as technological repositories and safe havens from the effects of Halo, in that it has a conventional external surface and a concave internal surface. It may be an indication that The Architect had a hand in designing both systems, but the Labyrinth remains totally separate from the Halo Array.

The installation itself is located approximately 86,000 lightyears from Sol, in the Scutum-Crux arm of the Milky Way galaxy. The territory controlled by the Forerunners vast, almost pan-galactic, and it is unsurprising that an installation should be located so far. The exact location, however, is a matter for debate - UNSC analysts had no time to study the ring, or to get their bearings by matching the stars with known stellar cartography. Regardless, the Governors of Contrition managed to return, using clues in arcane religious documents, and the Sovereigns managed to find it through extrapolation, interpretation of Forerunner relics, and coordination with other studies of the Labyrinth Worlds.


Regardless of why it was originally constructed, for the next 100,000 years the facility would lie dormant. Flood specimims were cultivated, studied by the facility's artificial intelligence constructs, but always kept under strict containment conditions. There are indications that other species have stumbled upon Mandorla before the 2552 campaign - the space above is littered with the debris of hundreds of strange and exotic spaceships, and the surface is host to the ruins of rudimentary settlements, spaceship crash sites, and other evidence of habitation. Whether they were eradicated as an unacceptable infection vector by the Sentinel guardians, or infected by the Flood during outbreaks, no intelligent species seems to have established a permanent presence.

Mandorla Campaign

Fighting on Earth during its invasion by the Covenant was intense, and spanned every continent. Most Covenant forces would eventually pull back to Africa after the New Mombasa artefact was discovered, defending the site as it was excavated by Scarabs and warships, but a significant detachment remained in Australia uncovering a second smaller artefact. The UNSC defence of their Papua New Guinea bases would allow them to launch a massive counterattack, supported by newly-arrived Sangheili Armed Forces warships and legions, pushing the Covenant back and eventually forcing them to go through the portal generated by the artefact to escape the combined assault.

All of this would end up being but a prelude to the Mandorla Campaign. Finding themselves in orbit above an unknown planet, far from UNSC or Covenant space, both sides would fight a pitched space battle before landing on the planet. Having been the first to enter the Portal, the Jiralhanae-led Covenant were also the first to land planet-side, and quickly set up defensive positions around key areas, including large anti-air turrets to prevent warships approaching. The UNSC Frigate Olympian launched ODST and Spartan forces to eliminate a number of these defenses, with enough turrets falling in the southern hemisphere to allow a combined UNSC and Sangheili attack on the entrenched Jiralhanae. SAF legions and UNSC Army and Marine divisions made rapid progress, pushing the Covenant north, capturing several Forerunner ruins in the process. ONI intelligence officials would document a few of these, but for the most part they were decaying remnants of ancient temples and habitats, long fallen into disrepair.

While all of this was happening, however, a Sangheili religions sect known as the Acolytes of Devotion arrived in a retrofitted stealth ship, hoping to find the "Labyrinth" detailed in arcane religious texts. Making landfall two months after the arrival of the Sangheili and UNSC, the Acolytes would come as a complete surprise to all three factions, forming their own as they captured several ruin sites from UNSC, SAF, and Covenant forces. Using their texts as rudimentary guides, the Acolytes achieved much as they explored the planet, eventually discovering that it was a prototype Shield World - that the interior of the planet was a completely separate habitat, and that the external shell was merely a facade. Penetrating deep into the planet, followed by UNSC and SAF special forces, the Acolytes would encounted the local security and containment forces set there by the Forerunner builders of the planet, fighting their way to what they believed to be the control panel for the entire Labyrinth network, apparently under the belief that it was a similar series of facilities to the Halo Array, meant to begin the Great Journey. This belief was mistaken.

Activating the facility, the Acolytes quickly discovered to their horror that they had only succeeded in unleashing the Flood specimins that had been stored deep within the planet. Infecting Acolytes, humans, Sangheili and Covenant forces alike, the Flood would violently break free of its containment by Forerunner constructs, attempting to make its way to the surface of the planet and capture a ship, hoping to spread throughout the galaxy again as it had before the activation of the Halo Array. Arrogantly unwilling to accept the threat the Flood posed, the Covenant forces quickly fell to the parasite, providing biomass for its rapid expansion. The Acolytes had perished when they had activated the Labyrinth world, but the UNSC and SAF both remained, although they had both lost at least half of their original force to the Flood. Now facing a rising tide of Flood monstrosities hoping to overwhelm their positions, using captured dropships and fighters to try and board the orbiting warships, the assault force was forced to abandon the planet, retreating back through the portal, bombarding the exit point between interior and exterior with nuclear weapons - effectively sealing the Flood within the planet. The portal generator in Australia would deactivate, collapsing the portal and preventing further access except by conventional slipspace travel - a journey that would take years for UNSC ships, and three months even for Covenant ships not equipped with cryionic storage facilities.

Second Great War

During the Second Great War the Governors of Contrition would journey to Mandorla as they attempted to claim various Forerunner artefacts in order to find the true purpose of the Labyrinth Array. Finding that the Flood had continued to multiply and the Sentinel containment forces were having a hard time simply surviving, let alone actually containing the Flood, the Governors attempted to activate the Labyrinth world. Though seven legions would march to their deaths, either incinerated by Sentinels or consumed by the Flood, the Governors would succeed in their goal, with Mandorla sending out a FTL beacon that, when considered in conjunction with that of Ares IV, eventually led the Governors of Contrition to the Nexus, and then to the Noumenon.

Third Great War

The planet would be visited a third time during the Third Great War, this time by a Sovereign taskforce who regarded it, as part of the Labyrinth Array, as part of their "heritage". Hoping to discover another Nexus node, and another way back to their home galaxy, they succeeded only in falling prey to the Flood, naively believing that theyr superior technology would allow them to easily overpower the voracious parasite. Using the Sovereign ships, the Flood would jump to the Noumenon, hoping to begin the infection of the Sovereign's home galaxy.





  • "I remember back in '52, we followed five Brute cruisers through the Sydney relic portal. I won't say it's as grand as the Ark, but knowing that you just jumped 85,000 lightyears in the blink of an eye is certainly something!"
  • "A mystery inside an enigma. My warriors reported only that the surface was barren, devoid of all but the most damaged relics. Then we follwed the Brutes as the invaded its hallowed interior, and discovered a second surface. Truly a work of the ancient ones - such a shame that it was lost to us when the portal closed."
  • "There's a lot of rumours about Mandorla - that it was a weapons cache, a treasure trove of Forerunner knowledge, or just a research facility. We just weren't there long enough to find out anything about it. Whatever it was, it's been overrun by the Flood - I doubt that will stop ONI trying to find out, but I think it will stop them succeeding."