Log.00: Synopsis

ARMORED CORE VI FIRES OF RUBICON (2023)

The story is set on Planet Rubicon 3, located in a remote frontier star system. Long ago, a mysterious energy substance known as “Coral” was discovered on this world, promising a monumental technological leap for humanity. However, the Coral suddenly ignited, triggering a uncontrollable phenomenon that engulfed Rubicon 3 and its surrounding star systems in flames—a catastrophic disaster known as the “Fires of Ibis.”

About half a century later, a resurging presence of Coral is detected on Rubicon 3, a world thought to have been completely burned to ash. Catching wind of this, off-world megacorporations—such as Balam Industries and Arquebus Corporation—encroach upon the planet, seeking to monopolize the vast profits the resource represents. In response, the native inhabitants form the “Rubicon Liberation Front” (RLF) to resist corporate exploitation. Furthermore, a public military authority known as the “Planetary Closure Administration” (PCA) intervenes to prevent unlawful corporate intrusion and contain the Coral, transforming Rubicon 3 into a vicious, three-way battlefield.

Into this war-torn land descends the protagonist, early-model augmented human “C4-621,” executing a solo illegal entry under the orders of their handler, Handler Walter. Lacking an official mercenary license, 621 illicitly acquires the callsign and license of a fallen independent mercenary found on the battlefield, henceforth taking to the skies under the codename “Raven.”

As an independent mercenary operating under Walter’s direction, 621 accepts contracts indiscriminately from both the corporations and the RLF. Through exceptional combat capabilities, 621 quickly commands the respect and wariness of all factions. Walter’s true motive, however, is to exploit the chaos between these powers to locate the Coral’s central convergence point.

During this pursuit, 621 assaults an old-generation facility known as Watchpoint Alpha. There, caught in a massive C-Pulse Wave Mutation, 621 establishes contact with “Ayre”—a sentient Coral wave mutation—via the early-gen Coral augmentation embedded in their brain. Existing solely as a voice inside 621’s mind, Ayre becomes an indispensable tactical navigator and companion.

Meanwhile, the conflict on Rubicon intensifies further. Facing the overwhelming force and technological dominance of the PCA, Balam and Arquebus forge a temporary truce to launch a joint alliance operation against the PCA’s heavy weapon, the Ice Worm. Through the heroic efforts of 621 and Arquebus elite pilot V.IV Rusty, the threat is destroyed, drastically shifting Rubicon’s power balance. With the PCA forced onto the back foot, the megacorporations resume their bloody struggle, plunging into the depths of the planet toward the “Coral Convergence.”

Reaching the ancient city built by the Rubicon Research Institute hidden deep underground, 621 engages and destroys the “IBIS Series”—autonomous mechs responsible for sparking the original Fires of Ibis. Immediately following this victory, 621 is ambushed and captured by Arquebus forces. Amidst the chaos, Handler Walter is also seized by Arquebus and goes missing.

The imprisoned 621 is rescued by “Cinder” Carla, leader of the Rubiconian junker faction “RaD” and an associate of Walter. At this juncture, the true affiliation and objective of Walter and Carla are laid bare: they belong to “Overseer,” a secret organization upholding the legacy of the scientists who survived the Fires of Ibis. Coral is not merely an energy resource, but a self-propagating collective entity; should it escape into the vacuum of space and reach a critical density, it poses the catastrophic risk of a runaway mutation and explosion capable of annihilating humanity. Overseer’s goal is not to monopolize the Coral, but to intentionally ignite the concentrated mass accumulated at the convergence, burning away Rubicon and the Coral entirely—kindling a second Fires of Ibis.

Escaping the detention facility in an obsolete AC, 621 reunites with Carla. By this time, Rubicon 3 has fallen under complete Arquebus military control, and the corporate giant is siphoning the Coral Convergence through a colossal structure called the “Vascular Plant.”

Carla initiates the final phase of their plan: utilizing the massive interstellar colony ship Xylem as a kinetic projectile to ram the Vascular Plant and incinerate the Coral. However, unwilling to see her kind eradicated, Ayre pleads with 621 to seek a path where humanity and Coral might coexist.

Here, the narrative reaches a pivotal junction, branching based on the player’s (621’s) choices.

Ending 1: The Fires of Raven

In this path, 621 sides with Carla and Overseer, choosing to honor Walter’s final wishes. 621 cuts down the forces of the Rubicon Liberation Front and Arquebus attempting to halt the Xylem’s advance, ultimately engaging and defeating their former comrade-in-arms, Rusty. In a last-ditch effort to prevent the destruction of her kind, Ayre projects her consciousness into a physical weapon system to stand in 621’s path. After a painful exchange of words and a grueling battle to the death, 621 defeats Ayre. The Xylem collides with the Vascular Plant, igniting the gathered Coral. Rubicon 3 is once again consumed by hellfire, triggering a system-wide catastrophe. The off-world corporations are obliterated, and Rubicon becomes a dead planet. Survivors dub this calamity the “Fires of Raven,” caused by the monster who became the worst mercenary in history, leaving a terrifying mark on human history as the story closes.

Ending 2: Liberator of Rubicon

In this path, 621 heeds Ayre’s plea, choosing to protect the Coral and Rubicon. 621 turns against Carla, opposing Overseer. To liberate Rubicon from Arquebus oppression, 621 supports the Rubicon Liberation Front uprising rallied by Ayre’s call and moves to prevent the Xylem from crashing into the plant. After destroying V.II Snail, Arquebus’s top commander, 621 reclaims control of the Xylem. However, in the final hour, Handler Walter appears—subjected to Arquebus’s inhumane “re-education,” stripped of his free will, yet driven solely by a lingering obsession to “burn the Coral.” After 621 is forced to cut down their owner, Walter regains his senses in his dying moments, finding peace in the realization that 621 has found their own purpose before ceasing to function. With both the corporations and Overseer eliminated, Rubicon is freed from exploitation. 621 and Ayre set out on an unwritten path toward a future where humanity and Coral might coexist.

Ending 3: Alea Iacta Est

Across multiple playthroughs, 621 begins accepting classified requests from ALLMIND, an AI posing as a mercenary support system. ALLMIND’s true goal is to forcibly trigger “Coral Release”—an unknown phenomenon that fuses the bodies of augmented humans with Coral wave consciousnesses, scattering and expanding Coral across the reaches of space. Seeing this as a third way distinct from both Overseer and the corporations, 621 and Ayre align with ALLMIND’s plan. After covertly eliminating Overseer and corporate interference, ALLMIND reveals its true intentions in the final stage, moving to assimilate the irregular anomalies—621 and Ayre—into its system. In the final confrontation, ALLMIND unleashes a massive mech driven by the integrated mind of V.VIII Iguazu, a rival mercenary harboring intense malice toward 621. Overcoming Iguazu’s deep-seated obsession and ALLMIND’s processing power, 621 and Ayre trigger Coral Release with their own hands. A singularity resembling a black hole opens, dispersing Coral far beyond Rubicon 3 across the entire cosmos. Countless Armored Cores scattered through space awaken simultaneously, lit by the glow of Coral. Whether this brings about human evolution or merely heralds a new era of endless strife remains unknown. With the iconic AC boot-up chime, “Main System: Activating Combat Mode,” the story comes to a definitive end, hinting at a universe thrust into a whole new dimension.