The Ultima Segmentum, the Damocles Gulf Theater.
A sea of wreckage floated silently in the void. What were once majestic warships were now twisted metallic skeletons tumbling through the dark expanse. Ruptured hulls exposed molten compartments inside, with severed conduits drifting weightlessly like torn veins.
A careful observer could easily distinguish the two opposing factions from their starkly different design aesthetics: the Imperium of Man, and the T'au. Intermingled in space, their shattered remains formed a silent monument to war. A fierce battle had clearly taken place here—hardly a surprise, as the Damocles Gulf was the Imperial frontier closest to the T'au homeworlds.
"Commander Shadowsun, your tactical command remains astonishing," an Ethereal Elder said with a subtle smile on the bridge of a Custodian-class Aircraft Carrier. Slender and clad in the white robes of the Ethereal Council, Elder Aun'Va—originating from the sept world of T'au—spoke with a gentle demeanor. Beside him stood the legendary commander herself.
Shadowsun's features were somewhat softer than those of a typical Fire Caste warrior, carrying a quiet composure. Her blue-grey face, however, remained expressionless as she offered a curt nod.
"You praise me too much, Elder. I merely contributed my humble part." Her tone was even, brushing the compliment aside like dust.
As one of the legendary students trained during the Second Sphere Expansion, Shadowsun, along with Farsight and Kais, had inherited their master's tactical doctrines. To prepare for future conflicts, the Supreme Ethereal Council had devised a deliberate strategy: keeping the three legendary commanders in stasis and awakening only one at a time, ensuring that top-tier military leadership was available across every era.
Shadowsun was the one awakened for this era.
Upon waking, the first news she received was not a battle update, but the shocking revelation that Commander Farsight—her closest brother-in-arms—had defected. The news struck her like thunder. Yet, as a resilient Fire Caste commander, she refused to let emotion sway her for long.
She adapted to the advanced T'au combat doctrines with astonishing speed, eagerly studying the upgraded weaponry data and fleet formations developed by the Earth Caste during her slumber. Then, true to expectations, she unleashed her tactical genius to expand the domains of the Greater Good.
According to the Supreme Ethereal Council, a massive galactic shift had occurred due to unknown reasons. Shadowsun did not fully grasp the details of these reports; as a Fire Caste soldier, interpreting the grander picture and guiding the destiny of the T'au was the sacred duty of the Ethereals. Since the Council had reached a unanimous decision, she obeyed without question. Execution was her sole responsibility.
Under the Ethereals' guidance, the Third Sphere Expansion—originally scheduled for nearly a century later—was launched prematurely. The T'au fleets swept forth, surging ahead to spread the Greater Good.
Then, they ran headlong into a wall.
Shadowsun turned her gaze toward the viewport. Across the void, the wreckage drifted. A few Imperial wrecks were surrounded by a vast quantity of destroyed T'au vessels—a grim testament to the toll of the battle, silently mocking her efforts.
Shadowsun's brow furrowed, a shade of gloom passing over her grey-blue eyes. She had performed to the absolute limit of her abilities. The Kauyon—the "Patient Hunter" tactic—had been executed to perfection. Using a small frigate force as bait, she drew the Imperial pursuit fleet into a kill zone, trapping the ancient void navy under overwhelming firepower.
Tactically, it was an undeniable victory. Yet the humans resisted with absolute ferocity. Even in total annihilation, they tore a far larger chunk out of her fleet than anticipated before dying.
Remembering the recent assaults on Imperial worlds, Shadowsun felt a knot form in her brow as she sank into deep thought. Things were becoming genuinely difficult to resolve.
The alien empire before her had undergone an incomprehensible shift since the Damocles Gulf Crusade a century ago. Data cores captured from Imperial ships and interrogations of human prisoners revealed information that shattered her worldview.
Rumors circulated among the Gue'la worlds that the so-called sons of their god had returned from death and slumber, systematically reforming every aspect of their decaying empire. Furthermore, several red-robed Gue'la—whom Shadowsun understood as the human equivalent of the Earth Caste—claimed that a true Machine God, the Omnissiah, had emerged in the galaxy to bestow enlightenment once more.
Consequently, human living conditions had improved, while their military structures and logistical networks underwent radical overhauls. Morale and combat will had surged, equipment had drastically improved, and the size and strength of their fleets surpassed historical Imperial Navy records by several orders of magnitude. In some respects, Shadowsun felt their progress was outpacing even that of the T'au.
This realization weighed heavily on her.
As a believer in the Greater Good, she rejected the concept of deities, holding that everything in the universe could be rationally explained. The ancient religions of the Gue'la were mere relics that belonged in the trash heap of history, entirely unfitting for an empire spanning the galaxy.
Yet despite her disdain, the visible surge in the enemy's martial capability was undeniable. Moreover, the directive assigned to her by the Council gave her a severe headache: rather than converting the Gue'la territories to the Greater Good, her orders were to utterly destroy the human worlds closest to T'au space as quickly as possible, establishing a fortress bridgehead and a buffer zone.
This order baffled her. What was the point of launching the Third Sphere Expansion early under such parameters?
A border-line sacrilegious thought briefly crossed her mind: Could Brother Farsight have harbors the very same doubts I feel right now?
"Elder, can you answer this question for me?" Unable to contain her doubts any longer, Shadowsun turned to the Ethereal.
Something felt subtly off about him. He maintained the same warm, gentle smile as any other Ethereal, yet Shadowsun sensed something unreadable lurking deep within his eyes.
The Ethereal offered a mysterious smile. "It is difficult to say. Perhaps this is simply the Council's wisdom. I am not fully privy to the details myself."
'Brushing it off again?' Shadowsun sighed inwardly. Still, as a soldier—and with Farsight's downfall serve as a warning—she would never betray the Ethereal Council or fracture the Fire Caste.
She withdrew her gaze, intending to refocus on her duties. She prepared to order the fleet to clear the battlefield, salvage the warship debris for Earth Caste reverse-engineering, and proceed with the next phase of the operation.
At that exact moment, Shadowsun froze.
Within half a second, her battlesuit shifted fluently into a combat stance, the barrel of her fusion blaster glowing with an eerie blue light.
There, inside the core bridge command area of the Custodian carrier—right beside the Ethereal Elder—stood a person.
A Gue'la.
The human stood there casually, looking around the bridge as relaxed as if he were in his own home. He gave a thoughtful nod.
"I see. So this is where my preset point landed. Quite a coincidence."
Blaring alarms instantly echoed across the bridge. Heavy footsteps sounded from the corridors, and swarms of drone escorts launched from hidden ceiling and floor hatches. Shadowsun kept her fusion blasters locked onto the figure, her aim rock-steady.
"Who are you? I do not recognize you," Shadowsun demanded sternly. "How did you get in here? Speak immediately!"
Having memorized the faces of every high-ranking Gue'vesa officer, she was certain this man's face appeared in no military file authorized to enter this space.
Adam chuckled softly. "To be honest, I'm a bit surprised myself that I landed right here."
Indeed. Having dealt with the Great Devourer beyond the galactic rim, his next task was addressing the T'au. To Adam, compared to other galactic factions with ancient legacies or powerful patrons, the T'au were remarkably straightforward to handle.
He had fought the others: Necrons possessed living metal and C'tan shards, Orks had the Waaagh! field, the Aeldari were elusive, and the Tyranids and Chaos were nightmare scenarios. The T'au, however, had already proven to Adam that they possessed zero resistance to reality-warping.
Resolving them first was the obvious choice. To reach T'au space quickly, Adam had simply thought of the only Ethereal whose location he remembered: Elder Aun'Va. A single thought, and he arrived.
"What?!" Shadowsun watched in sheer terror as Elder Aun'Va turned around.
The serene, iconic smile remained on the Ethereal's face. Then, the representative of the supreme will of the Greater Good respectfully dropped to his knees.
"Master, you have arrived," the Ethereal said, his voice calm and devout.
Shadowsun's eyes widened in horror.
The Ethereals were the ultimate authority of the T'au, the very core of their unity. Under their command, T'au warriors fought without fear of death. Their existence was the foundation holding the empire together.
And now, an Ethereal was kneeling before a Gue'la.
"How is this... possible...?" Shadowsun's breath hitched, her voice cracking.
Driven by raw instinct, she tried to direct her battlesuit's weapons toward the Ethereal. Yet her body refused to move. The neural link was functional and the suit's targeting systems were operating normally, but the command to fire simply could not travel from her brain to her weapons.
It was identical to the sensation of standing before an Ethereal.
"What did you do to him?!" Shadowsun roared.
"Well," Adam shrugged lightly. "Honestly, this kind of thing is pretty common in this universe. Ever heard of Warp corruption? Ah, right—I almost forgot your souls are too dim to understand any of that."
Having a dim soul certainly had its perks. Adam couldn't quite fathom it himself; while a faint warp reflection helped the T'au resist basic Warp corruption—like that Fire Caste commander who remained completely unaffected on a Nurgle-corrupted ship, mistaking plague zombies for insane humans—how did they hold up against direct mental control? The Necrons had Mindshackle Scarabs, yet somehow the Ethereals had kept their grip unchallenged until now.
'Corruption?!' The word made Shadowsun's pupils contract.
She scrambled to piece together her limited knowledge. Was this some form of Imperial mind technology? A form of control she had never encountered?
Instinct urged her to act. Even at the cost of her life, she had to transmit this intelligence—to warn the Supreme Ethereal Council and all T'au that the Gue'la possessed the technology to control the Ethereals!
Yet her body remained completely immobilized.
"Relax," Adam said, his tone turning lighthearted, as if discussing mundane matters. "By the way, how do I get to the T'au homeworld?"
As the Ethereal prepared to answer respectfully, Adam waved his hand dismissively. He tilted his head slightly, as though reading from an invisible document.
"Ah, never mind. Found the coordinates in your memory."
Adam turned around as his figure began to fade, like a stone dropped into a mirror-like pond, causing ripples along his outline.
"It doesn't matter anyway. As followers of the Greater Good, haven't you always wanted to integrate humanity into the T'au Empire?"
Shadowsun's face remained frozen in horror as the human's figure dissolved into thin air, leaving his voice echoing behind:
"If that's the case, I think your wish is about to come true."
"—Just, in reverse."