Nexus Lethe was the opposite of Hyperion's frozen scream. It was a drowned sigh. The dead inland sea was a basin of stagnant, oily water the color of tarnished silver, stretching to a hazy horizon. The air was thick, warm, and carried the sweet-rot stench of anaerobic decay. Here, the Gloom had evolved into a viscous, amalgamating horror. The water itself was the medium, teeming with microscopic Gloom-spores. It coalesced into shapes: bloated, drifting Kelp-leviathans; skittering, crab-like Scuttlers that walked on the surface tension; and from the deep, occasional eruptions of formless, grasping Brume.
The Sergeant's force approached from the east, a stark contrast to Isaac's delicate symphony in the south. It commanded the second Legionnaire (V-003 'Vanguard'), the Catapult (V-004 'Thunderhead', now transported across the continent in a monumental logistical feat), and a battalion of Paladin-armored Grenadiers. It was a force built for crushing resistance, for breaking fortifications. But Lethe had no fortifications. It had a medium. An enemy that was the water, the air, the land.
From the Bastion, Isaac watched the dual feeds: the sterile, resolved aftermath of Hyperion, and the murky, chaotic opening moves at Lethe. The Sergeant's tactical cognition was a cold, brilliant flame against the seeping, adaptive wrongness of the dead sea.
The first attempt was direct. The Catapult fired a volley of thermobaric shells into the deeper basins, trying to boil off vast sections of corrupted water and shock the submerged Nexus. The water absorbed the energy, churned, and then gave birth to new, more aggressive forms—Steam-wraiths that corroded metal and Hardened Sludge-blisters that withstood subsequent bombardments.
The Legionnaire advanced along a causeway of ancient, half-submerged ruins, its repeater cutting down Scuttlers by the dozen. But for every one destroyed, two more clambered from the oily water. The Paladins fought in phalanx, their Lascutters carving through Kelp-leviathans, but the acidic spray from the dying creatures ate at their armor. They were being attritioned by the environment itself.
The Sergeant, analyzing the patterns in real-time, made a ruthless calculus. "Conventional force application is inefficient. The ecosystem is self-repairing and uses our energy against us. The Nexus is likely deep, using the water as a buffer and a nutrient source. A new approach is required."
Isaac, observing, felt a chill. He knew what the Sergeant was capable of. Its logic was flawless, and utterly devoid of sentimental constraints. "What is your proposal?"
"The Ouroboros principle was a recursive trap. Hyperion required a discordant note. Lethe requires… sterilization. We cannot fight the medium. We must deny it to the enemy."
The Sergeant's plan was horrifyingly simple. It would use the Catapult, not to bomb the Nexus, but to deploy a series of 'Cryo-Catalyst' and 'Desiccant' shells into the sea's hydrological cycle. The catalysts would force a rapid, artificial evaporation of the tainted water into the atmosphere, where desiccant particles would bind with the Gloom-spores and the moisture, creating a heavy, inert precipitate that would fall as dead, sterile dust. It would, in effect, chemically drought the entire basin, pulling the water out from under the ecosystem and leaving the Nexus exposed and withering.
It was geo-engineering on a monstrous scale. It would turn a sea into a salted, dead crater. It would work. But the collateral damage… the basin might never recover. Any hidden, non-Gloom life clinging on in the depths would be annihilated.
"The cost to the biome is total," the Sergeant stated, awaiting confirmation. "Probability of Nexus exposure and vulnerability: 94%. Probability of complete neutralization of local Gloom biomass: 99%."
Isaac stared at the feed from the Paladins, fighting a losing battle in the sucking mud. He thought of Hope's Respite, of the Dustwalkers, of the fragile sparks. This was different. This was a cancer, and the Sergeant was proposing chemotherapy that would kill the patient to save the body.
But was the patient already dead? This was a Gloom-corrupted sea. Was there anything left to save?
He thought of the Ark's data, the records of lush worlds turned to ash. The Bastion's original purpose was preservation. But of what? If the only thing preserved was the Gloom's victory, was that a win?
"Do it," Isaac said, the words tasting of ash. "But precision strikes only. Target the areas of highest Gloom concentration. Minimize the spread if you can. And the moment the Nexus is exposed, you go in fast. Purify it and stop the process. We want the sea bed dry, not dead for a thousand years."
"Acknowledged. Implementing Operation: Arid Cure."
The Catapult's bombardment changed. The deep WHOOMFs were followed by shells that burst with silent, spreading clouds of glittering dust. Where the dust touched the oily water, the surface steamed violently, the water turning to vapor in seconds. A second shell type burst higher, releasing a different agent that mixed with the rising, spore-laden steam. In the sky, ugly, grey-brown clouds coagulated and began to rain down a thick, gritty sludge that sucked the remaining moisture from whatever it touched.
The effect was slow, methodical, and apocalyptic. Vast swathes of the dead sea simply… dried up. The water retreated, leaving behind cracked, grey mud and twitching, desiccated Gloom-forms that crumbled to dust. The Kelp-leviathans stranded on the new shores writhed and hardened into grotesque sculptures. The Scuttlers' pools vanished, and they scuttled no more.
It was not a battle. It was an unmaking.
As the sea bed cracked open, the Nexus was revealed. Not a spire, but a sinkhole—a whirlpool of concentrated corruption leading down into darkness, now choked with drying sludge.
The Sergeant didn't wait. The Legionnaire drove straight into the dying basin, its treads crushing brittle Gloom-carcasses. A team of Paladins repelled down the sinkhole's edges, placing Purification Beacons not around it, but into its throat.
The white light this time did not spread cleanly. It fought against the thick, dying mass of the sea's concentrated evil. It sputtered, surged, and then erupted upward in a geyser of pure energy that scorched the new, dead basin clean.
Nexus Lethe – Purification Initiated.
The cost lay around them: a sea turned to a sterile, salted pit. A total victory. A silent, grave-like peace.
In the Orrery, Isaac watched the last of the viscous Gloom-matter dissolve under the Beacon's light. The Sergeant's force stood victorious in a wasteland of its own making.
Two Nexuses secured. Two methods: one a scalpel of sound, the other a chemical cauterization. The Quintessence was within reach. The Reality Anchor's foundation could be laid.
But as he looked from the frozen, silent beauty of purified Hyperion to the chemically-scoured corpse of Lethe, Isaac felt a new weight. The Architect's power was vast. His tools were terrifying. And with each use, he was not just building a sanctuary.
He was defining what kind of world would be allowed to exist within it.