The Horizon System: Elysia, the Imprisoned Prometheus
Deliver us, mighty Lords!
Help us, gracious Archons!
Our hope is lost, our plans have failed, the barbarians have breached the gates -
Save our souls from the Terror of Horizon!
- Condemnation of the Archon of the Gilded Underworld, ‘Cassytha’ [Inconvenient Queries of Unconventional Ethics]
Elysia (Torrid Superterra, Planet)
System - Horizon-Actinophrys
Mass - 5.774 Earths
Radius - 9,840 kilometers (1.544 Earths)
Global Average Temperature - 1103°C
Day Length - ∞ (Tidally Locked)
Year Length - 12.69 days
Number of Satellites - 0
ESI - 0.148
Etymology - From Elysia marginata, a sacoglossan leaf slug, for its colors and penchant for regenerating its body.
Overview
Flaming, viridescent Elysia is one of the more flamboyant of Actinophrys’s rocky worlds. With surface temperatures pushing 1300°C, it is well on its way to violent evaporation. Halide minerals in the crust have broken down, releasing fluorine and chlorine into the atmosphere to form a choking mix of elemental halogen gases, hydrofluoric and hydrochloric acid, water vapor, and carbon dioxide which is a strong contender for the most unbreathable atmosphere in the known universe.
The surface is no more hospitable than the atmosphere either - wracked by powerful volcanism, steaming oceans of semi-molten lava cover a full half of even the cooler night side. Convection currents in the magma oceans that underlie the crust rip off chunks of volcanic rock from the weak solid crust that drift through the open lava seas like hellish icebergs, while volcanoes anchored in the cooler continental cores erupt constantly to make up for these losses. Over the course of weeks or months, practically all of Elysia’s surface is replaced.
Past & Future
Elysia, like most of the terrestrial planets of Actinophrys, is unusually rich in water, ammonia, methane, and hydrogen. Though its halogen-rich atmosphere is too reactive to allow these gases (save water) from persisting in their unmodified forms, they are emitted in huge quantities from the deep mantle. There is so much hydrogen in particular that Elysia must have been completely saturated with the gas at some point in its history, which would have made it a mini-Neptune. As it is not a mini-Neptune today, something must have happened to remove its thick atmosphere later in its history.
Though Elysia is too hot to retain hydrogen indefinitely, it loses the gas at a rate low enough that volcanism should have been able to replenish it. This fact combined with exceptional enrichments of the alpha elements calcium-44, titanium-48, chromium-52, and iron-56 suggest that the Horizon System took a core-collapse supernova nearly point-blank not long after it formed. The supernova shock that swept over the system would have forcefully stripped Elysia and the other small planets of the system of their hydrogen atmospheres, transforming them from mini-Neptunes into super-Earths with rocky surfaces.
Civilization
Elysia appears as a green star separated from Actinophrys by at most 3°, prominently visible alongside its fellow Interior Semiresonant Series members Chrysaora and Tridacna just before sunrise and just after sunset. The bright lime green color of the planet is unlike that of any other object in Horizon’s night sky and is strikingly close to the color of the Horizonian sapients’ hemovanadin-rich blood. This resemblance associates Elysia with warfare and violence in most Horizonian cultures throughout history, an association that remains strong in those few populations that have survived to today.
All of the reservations against exploration that apply to Chrysaora also apply to Elysia in a more mild form. While the hot, halogen-rich atmosphere of Elysia could be a useful reagent for industrial chemistry, it is far easier to conduct such industry elsewhere instead of shipping it here, even with the sheer quantities of production an interstellar civilization demands. Unlike Chrysaora, it is actually possible to orbit Elysia, so it has been explored relatively extensively by solar-shielded spacecraft. It is however practically impossible for even robotic probes to survive on its surface, so the planet has been left entirely to nature. A small set of station settlements has been constructed in Elysia’s orbital space, but none approaches the planet closer than a few million kilometers. All are mostly self-sufficient, as the Horizonians have little to desire from them.
Whispers from the Reach
If you are hearing this broadcast, it is already too late.
There is a Leviathan in the seas of Thalassa. It wears the faces of distant lovers and speaks in the voices of lost brethren. It slinks through devilish night, whispering words of sweet sedition into the hearts of the most stalwart of soldiers and parroting the dying screams of valorous warriors torn apart by its millions of gnashing maws. An endless flood of deathless beasts pours out of the black abyss like a howling tide while the Commissars choke on blistering venom in the dead of night and the wails of damned men subject to unspeakable torment rise like howling winds from the hellish undergrowth.
We tried to fight it. By the grace of His Majesty the God-Emperor, we tried. Countless brothers and sisters threw themselves at the beast with courage in their hearts and His name on their lips, but all for naught. The lucky ones were only killed, chewed up by the flesh-eating tide or crushed by its weight. Much worse awaited those they took alive. I saw men turned inside-out, devoured by their own entrails imbued with unnatural, ravenous life. I saw others torn apart, folded and contorted across an infinity of acicular dimensions shimmering with their undying agony. I saw yet others amalgamated into mindless shambling beasts, pulsating with Heretical carnomancy. The young sons and daughters of the Emperor they twisted with their vile sorcery, warped by the devil of Proteus into demons equal parts man and machine. The fields run red with spilled blood and the lashing heat drives the smell of death and the screaming rings out through the waves - and it has always been like this.
They may call us heroes, but no amount of praise from the Office of War will ever blind me to the truth. My comrades were not saints martyred while delivering the Reach from evil. They were but scraps of meat tossed to stuff the hungering maw of an unknowable monster.
For what fools are left to hear this, listen to me. The Crinoid’s Tower is lost. The infidels have broken the stalwart walls of Hesperia wide open. There is nothing left in these condemned lands but death and ruin.
May you run fast and far, to never return.
May His Majesty save us all.
The last broadcast made by units from the now-defunct Holy Hesperian Empire in the Thalassa System during the Broken-Star Campaign of the Vitalist Wars (2229-2281).
The Vitalist Wars were an exceptionally long and damaging conflict that plunged much of the Gordian Reach into chaos for most of the 23rd century. They were the largest interstellar conflict since the Cerulean Demise, outclassing even the Great Dissonance of Horizon in terms of length, damage, and physical expansiveness. What began as a small religious dispute between minor members of the Righteous Alliance of Outer-Rim Sovereigns (RAOS) and the Hegemonic Foundation devolved into a decades-long omnicidal apocalypse as the political web of secret deals and overlapping treaties ensnared dozens of ambitious regional powers. By the end of it, the conflict had gotten so convoluted and so multi-sided that the surviving belligerents practically forgot what they were supposed to be fighting for. What remained was a struggle of all against all, of hateful retribution that scarred the skies with artificial supernovae and left some 5% of the Reach uninhabitable for complex life.
By the 2270s, the collapse of the Deathless Empire of Horizon threatened to pull the neutral provinces of the Euplokamis Spine and the Comatula OB Association into the war. To prevent the situation from spiraling out of control into a second Cerulean Demise, the Oneirodean Mysteries’ Dread Hunt and the Miaolingian Institute of Natural Sciences (MINASE) conspired to forcibly terminate the Vitalist Wars in what is now known as the Broken-Star Campaign. Within the first hundred days of the year 2281, MINASE operatives had secured a diplomatic armistice in thirteen nations, established an informal ceasefire in forty-three others and forcibly dissolved the governments of a final nine. The main belligerents, on the other hand, were deleted from history by the Dread Hunt.
In the following years, the Oneirodeans permanently erased all records of their existence from the galaxy while the MINASE purged its archives of its own activities, leaving the remaining civilizations of the Gordian Reach once again ignorant of their latest flirt with utter annihilation. Perhaps someday they will be doomed to repeat their mistakes and bleeding chaos will once again rule the galaxy.
