Salt & Steel: World Overview — The Shattered Expanse
Document type: World & Lore — Foundational
Status: Canonical
Last updated: 2026-04
See also: Factions & Civilizations | Mythology & Supernatural | History & Timeline | Creative Identity
Overview
The Shattered Expanse is not a world. It is what remains of one.
Once there was a supercontinent — vast, ancient, unified under the sprawling empire of the Urrathi, the First People who raised cities to the clouds and plumbed the deepest trenches for the secrets of the old gods. Then came the Reaching — the hubris of a civilization that grasped for divine power — and then the Cataclysm, and then the sea.
The sea rose and swallowed the old world. Whole continents sank. Coastlines inverted. Rivers became ocean trenches. What had been mountain ranges became archipelagos. The Urrathi's great cities, their libraries, their machines of impossible wonder — all drowned. And from the ruins of that catastrophe, over two thousand years of slow forgetting and hard rebuilding, a new world emerged.
That is the world the player inhabits. A world of ten thousand islands, each one the tip of something that was once greater. A world of sea lanes between scattered civilizations that barely remember they share a common ancestor. A world where ancient power leaks upward from the drowned ruins below, warping the sea and the sky and the minds of those who sail too close to where the old world breathes.
This document describes that world: its geography, its cosmology, its age, and the shape of the human civilizations that now press against each other across the endless water between them.
The World Itself: The Shattered Expanse
The Name
The people of the current age call it many things. The Aurantine Concordat calls it Mare Totum — the Total Sea. The Maelstrom Confederacy's pirates call it simply the Deep, or the World, as though no distinction is necessary. The Tidecallers, who understand it better than anyone, call it Yavarath — the Wound That Breathes.
The scholars of the Jade Fleet, whose records predate all others, use a term that translates roughly as "the place where the world broke and the sea remembered." Shortened: Shattered Expanse. That name has spread into common use because it is honest. The world is shattered. The expanse is what remains.
The Shape of Things
The Shattered Expanse covers an area impossible to fully chart. Estimates range from scholars at the Aurantine Academy, who calculate the navigable sea at roughly forty million square nautical miles of explorable water, to Jade Fleet navigators who claim the full Expanse — including the uncharted Outer Reaches where no reliable returning voyager has ever sailed — is three times that or more.
What is charted and known, from the perspective of a captain sailing the current age, divides into six major regions. These are not political designations but geographic and climatic ones — the sea itself is the territory, not the islands within it.
The Ember Seas — the world's heart, as far as any common sailor is concerned. Warm. Volcanic. Dangerous and beautiful in equal measure. The Ember Seas sit atop the ancient core of the old continent's interior, where the Cataclysm's fractures run deepest and the old gods' power seeps most freely. It is here that piracy was born, thrives, and defines itself. The Ember Seas are home to the Maelstrom Confederacy, the Aurantine Concordat's richest trade routes, and dozens of island nations too small to be empires and too proud to be anyone's colony. The water is warm blue-green in the shallows, deepening to a vivid dark teal, then to the near-black of the trenches. Volcanic islands rise from the sea with dramatic verticality — steep cliffs of black basalt, jungle that clings to impossible slopes, harbors carved by old lava flows into natural protection. The sea here glows at night where bioluminescent organisms thrive in the thermal upwellings. It is the most alive sea in the world.
The Drowned Reaches — to the east and south of the Ember Seas, where the sea is deeper and older. Here the ancient continent's lowland civilizations went under deepest, and the ruins they left are still standing — towers that rise from coral reefs, submerged palace complexes now colonized by sea-life, entire city grids visible through sixty feet of clear water. The Drowned Reaches are calmer on their surface than the Ember Seas — the water is darker, cooler, and stiller. But beneath it, the ruins generate strange currents, magnetic anomalies, and zones where the Veil between the mortal sea and the realm of the Drowned grows thin. Few permanent settlements exist here. It is a place for treasure hunters, ruin-divers, and those willing to risk what stirs in the deep.
The Frozen Straits — the far north, where the sea turns black and cold and the ice comes down in winter to close the passages entirely. The Frozen Straits are a maze of narrow channels between ice-capped islands and fjord-cut coastlines, where whale-hunting cultures have survived for thousands of years in conditions that would kill an unprepared southern sailor within days. The sky here does things it does nowhere else — in winter, the Lightspill, a curtain of shifting color across the night, is attributed by local mythology to the old gods exhaling from beneath frozen seabeds. The Frozen Straits are the region with the fewest Cataclysm fractures, which means less magical interference but also means the old powers that do emerge here are unfamiliar and strange — adapted to cold and ice in ways the Ember Seas' supernatural fauna are not.
The Storm Wastes — a region in the far west where the Cataclysm struck with particular violence and where the sea has never quite recovered. The Storm Wastes are a permanent weather system — not one storm but the residue of the Cataclysm itself, a rotating complex of hurricanes that has not fully broken in two thousand years. Sailors who have made it into the Storm Wastes and returned describe islands of impossible richness sheltered within the storm's eye — places where the old world's treasures washed together and accumulated, protected by the very weather that makes reaching them nearly impossible. Most captains regard the Storm Wastes as the ultimate final destination: the place where the greatest prizes wait, accessible only to those who have mastered everything the sea can teach.
The Jade Currents — to the far east, where the ocean flows differently, guided by deep-water currents the Jade Fleet has mapped over centuries. The Jade Currents region is the most politically organized sea in the world — the Jade Fleet's civilization has occupied these waters for three thousand years and treats the sea lanes as their territory in a way that even the Aurantine Concordat, with its vast navy, respects. The islands here are larger, older, and more densely inhabited than elsewhere. The architecture is distinct — buildings designed for the monsoon trade winds, cities built on river deltas where fresh water meets the sea. Sea dragons — creatures unknown in other regions — inhabit these waters, sometimes in cooperative relationships with the Jade Fleet's navigators.
The Obsidian Deep — not quite a region in the geographic sense, but a designation for the network of deep-ocean trenches, volcanic vents, and seafloor fractures that connect the world's known regions through their undersides. The Obsidian Deep is accessible, in theory, through any sufficiently deep diving operation. In practice, the pressure, the darkness, and the presence of things that live at those depths make it the most dangerous exploration zone in the Shattered Expanse. The Cataclysm's original wound is somewhere in the Obsidian Deep — the place where the Urrathi's Reaching tore the world open and where the old gods, disturbed but not destroyed, still stir in their age-long sleep.
Cosmology: The Old Deep and the New Sky
The Two Faiths of the World
The Shattered Expanse contains no single religion, no unified theology, and no god who claims universal authority. What it contains instead are two competing metaphysical frameworks, each supported by genuine supernatural evidence, each in fundamental tension with the other.
The Faith of the Deep is old — older than the current civilizations, older than the Cataclysm, possibly older than the Urrathi themselves. It holds that the world's true powers are the entities that existed before humanity: the Old Gods, who sleep in the deepest trenches of the Obsidian Deep, whose dreams send up the thermal vents and the bioluminescence and the magical currents that run beneath the ocean like nerves. These are not gods in the sense of beings who answer prayers. They are vast, inhuman presences — forces of nature with will but not intention, power but not purpose as any human mind could parse it. The Tidecallers, who have devoted their civilization to understanding and communicating with these powers, describe the Old Gods as "the ocean thinking about itself."
The Faith of the Deep is not optimistic. It acknowledges that the Old Gods are not benevolent, that their power is dangerous, and that the Cataclysm was the consequence of the Urrathi disturbing them. But it argues that these forces are the world's true nature — that the sky, the sun, the wind are secondary to the deep and the dark and the things that live without light. To sail the sea is to sail atop the Old Gods' dreaming body. To respect them is to respect reality. To ignore them is to court the fate of the Urrathi.
The Faith of the New Sky emerged in the age of rebuilding. It is practical, human-centered, and optimistic in ways the Faith of the Deep cannot be. Its deities are not sleeping monsters in the deep but personified forces of seafaring: the Navigator, who guides the lost; the Ironbreaker, who forged the first chain that anchored the first ship; the Three Sisters, who embody the three winds (fair wind, headwind, and storm). These are gods who answer prayers, or at least gods whose priests claim they do. Their temples stand at harbor mouths. Their festivals coincide with sailing seasons. They are gods made by and for people who need the sea to be navigable, survivable, and ultimately controllable.
The Faith of the New Sky does not deny the Old Gods. It argues instead that they are defeated — that the Cataclysm, terrible as it was, broke their hold on the world and reduced them to background noise. The new gods filled the space the old ones left. The sea belongs to those who sail it now, not to what sleeps below.
Most people hold some version of both faiths simultaneously, giving practical worship to the New Sky's gods for daily sailing and treating the Faith of the Deep with the wary respect one gives to a dangerous animal that is, so far, caged.
The Old Gods
The Old Gods have no single list — different traditions count different numbers and different natures. The most consistent accounts describe five major presences in the Obsidian Deep:
Yavarath the Wound — the entity closest to the surface, the one whose sleep is most disturbed. Yavarath is not fully an Old God in the same sense as the others — it is what the Cataclysm created when the Urrathi's power tore the seabed. It is the wound itself, given a kind of consciousness by the energy that flowed through it. The Leviathan Cult worships Yavarath specifically, seeking to tear the wound wider.
The Great Sleeper — a presence of vast, cold intelligence in the deepest trench of the Obsidian Deep. Neither malevolent nor benevolent — simply old and vast and dreaming. The Tidecallers believe the Great Sleeper's dreams are the source of the magical currents called Ley Lines of the Deep. Its name in the Tidecaller tradition is unpronounceable by most who haven't studied their vocal training.
The Tidemother — the Old God most associated with the sea's surface behavior. Storms, tides, and the great gyres of ocean current are attributed to the Tidemother's moods. She is the Old God most often personified as humanoid by surface religions, usually as a woman of impossible size who combs her hair with uprooted sea-mountains. Her relationship with the Faith of the New Sky's Three Sisters is contested — some scholars argue the Sisters are the Tidemother fractured by the Cataclysm.
The Drowned Fleet — not a single entity but a collective: the accumulated consciousness of every ship and crew that has gone to the bottom of the sea. This is less an Old God than an emergent supernatural fact. The sea remembers what it swallows. The Drowned Court — the supernatural undead faction — is in some sense the Drowned Fleet's avatar, the part of this vast collective that has developed enough individual will to act in the world.
The Unnamed — a presence in the Obsidian Deep about which genuine accounts agree only that it exists, it is very old, and it should not be disturbed. The Jade Fleet's oldest records contain a chapter simply titled "Do Not Read This Chapter" — and the chapter after that contains the only detailed description of the Unnamed, written in a script that causes headaches after sustained reading. The Unnamed is the one supernatural subject on which the Tidecallers and the Lighthouse Keepers agree: leave it alone.
The Power Leaking Upward
The Cataclysm did not merely break the world's surface. It cracked the boundary between the material ocean and the deeper reality beneath it — what the Tidecallers call the Veil. Through these cracks, the Old Gods' energy seeps upward, creating the supernatural phenomena that define the Shattered Expanse's world.
This upwelling power is not malevolent by nature. It is simply there, as electricity is simply there — dangerous if mishandled, useful if understood, impossible to eliminate. It powers the Ley Lines of the Deep, creates the magical currents that the Tidecallers navigate and the Jade Fleet's navigators exploit. It causes the bioluminescence in the Ember Seas. It creates the Lightspill in the Frozen Straits. It fills cursed artifacts with power and fills cursed captains with something that is both a gift and a sentence.
It also creates the world's monsters, or rather creates conditions in which the impossible becomes possible: creatures of impossible scale and supernatural nature that the natural world would not otherwise produce. The sea is not merely full of large things. It is full of things that should not exist — and yet do, and have, for longer than anyone has been counting.
The Current Age: The Age of Sail and Sorcery
Two Thousand Years of Forgetting and Rebuilding
The Cataclysm killed most of what existed. The first five hundred years after it — the Dark Tides — were a story of bare survival: scattered populations clinging to the highest ground, fishing from ruins, slowly learning to build ships from the wreckage of what had been. The next five hundred years — the Age of Rebuilding — were a story of re-emergence: new civilizations finding their feet on whatever ground remained, trading with neighbors, discovering that the sea was not just a death trap but a road.
The last thousand years — the Age of Sail, recently shading into the Age of Piracy — have been a story of expansion and conflict. Trade routes connect the scattered island nations. Empires have risen and sent their navies out to claim territory. Merchants have grown rich enough to challenge the old aristocracies. And in the spaces between the empires, in the ports that no one fully controls and the sea lanes that run outside any navy's consistent patrol, piracy has become both a profession and a philosophy.
This is the age the player enters.
Why This Age?
The Age of Piracy is, in every meaningful sense, the most interesting moment in the history of the Shattered Expanse. The world is large enough to be worth sailing, organized enough to have things worth taking, and still unsettled enough that what you take and what you build matters. The old powers — the ancient magical inheritance of the Urrathi, the sleeping presences in the deep — are beginning to stir again, because people keep sailing into the ruins and pulling things out of the dark, and every artifact recovered is another thread pulling at a knot that two thousand years of careful forgetting has barely contained.
The empires are powerful but not omnipotent. The pirates are free but not safe. The seas are charted but not fully known. The old world is silent but not dead.
Everything is in motion. The next hundred years will determine whether the world rebuilds into something better than what came before, or whether it makes the Urrathi's mistake again and reaches for a power it cannot hold.
The player is a captain entering this world with a ship, a crew, and the salt-and-steel combination of grief and resolve that makes a legend possible.
Major Geographic Regions: Design Specification
The Ember Seas (Launch Region)
Climate and Character: Tropical and volcanic. The Ember Seas take their name from the volcanic activity that continuously reshapes their geography — new islands appear (small, smoking, often temporary), old ones collapse back into calderas, and the entire region sits atop a network of magma chambers that make the seabed unstable and the supernatural phenomenon density the highest in the world.
Distinctive Visual Identity: Deep saturated blues and teals in the open water, vivid green of jungle on every island that has cooled long enough to grow one, black basalt cliffs, steam rising from volcanic vents at sea level, the electric blue-green of bioluminescent waters at night. In volcanic zones, the water around active vents glows amber from below. The sky during the dry season is spectacularly clear; during storm season, the clouds build into towers that the old pirates called "the black pillars holding up heaven."
The Human Presence: The Ember Seas are the most politically contested region in the world. The Aurantine Concordat controls the major trade routes and several of the larger islands. The Maelstrom Confederacy — the player's starting faction — claims the lawless spaces between Aurantine control. Dozens of smaller polities, island nations, free ports, and contested territories fill the gaps. The Ironclad Dominion has a growing presence, particularly around the deeper volcanic islands where the seabed mining operations they favor are most productive.
Supernatural Character: The Ember Seas' volcanic nature means frequent Ley Line activity. Cursed artifacts surface regularly from the seabed. The bioluminescence, while partly natural, is partly an expression of the old power seeping upward — and on certain nights, the glow has been known to form patterns that resemble the Urrathi characters that survive in ruins. The region's monsters are diverse, colorful, and dangerous in ways that reflect the chaotic energy below.
Gameplay Identity (Launch): This is the player's home sea — the region they learn to navigate, the factions they first engage with, the sea lanes they first master. It is designed to be richly varied within a single region: volcanic dungeon interiors, tropical island exploration, the complexity of Aurantine port politics, the chaos of Maelstrom Confederacy governance, the mystery of Urrathi ruins visible just below the surface in a hundred locations. The Ember Seas must sustain player engagement through all of the game's foundational systems.
The Drowned Reaches (Expansion 1)
Climate and Character: Temperate to subtropical, calmer than the Ember Seas on the surface but deeply unsettling below it. The Drowned Reaches are where the old continent's lowland civilizations — the great river-delta cultures that preceded even the Urrathi in some places — went under during the Cataclysm. The water is clearer here than anywhere else in the Expanse, which means the ruins are not hidden — they are simply unreachable without diving.
Distinctive Visual Identity: The contrast between the calm, glassy surface and the visible complexity beneath it is the defining visual quality of the Drowned Reaches. Looking down from a ship on a clear day, you can see palace domes, collapsed towers, intact street grids, all filtered through forty to eighty feet of water and colonized by coral and sea-life into something that is simultaneously ruin and reef. The color palette skews toward deep blue-greens, the warm golds of old stone visible through water, the vivid colors of coral and sea-life claiming the abandoned structures.
The Human Presence: The Drowned Reaches have few permanent inhabitants. The Sunken Crown pirate faction makes its base here — treasure hunters obsessed with what lies below. Aurantine salvage operations work the shallower ruins. The Drowned Court, the supernatural faction of cursed undead, have their strongest presence here, drawn to the ruins of civilizations older than the Urrathi.
Supernatural Character: The Veil between the mortal world and the realm of the Drowned is thinnest in the Drowned Reaches. Ghost sightings — actual ghostly apparitions, not just legend — are common. The ruins generate strange effects: voices in still water, lights that appear below without any visible source, the sensation of being watched from below. And occasionally, something from far below rises to the surface.
Gameplay Identity (Expansion 1): The Drowned Reaches introduce underwater exploration as a fully developed mechanic. Diving into ruins, navigating the pressure and darkness, managing breath and equipment, encountering what lives in the deep-shallow ruins — all of these build on the Ember Seas' foundation while adding a genuinely new spatial dimension. The expansion's narrative centers on the mystery of what actually existed before the Urrathi — an older civilization whose ruins the Urrathi themselves built on.
The Frozen Straits (Expansion 2)
Climate and Character: Sub-arctic to arctic. The Frozen Straits are a labyrinth of narrow passages between ice-capped islands and fjord-cut coastlines, navigable in summer with skill and courage, closed by ice for months each winter. The whale-hunting cultures of the Straits have built their civilization around the rhythms of ice — they know which passages freeze first, which are navigable longest, where the ice can be trusted to walk on and where it cannot.
Distinctive Visual Identity: The Frozen Straits are visually the most distinct region in the Expanse. The color palette is blues and greys and whites punctuated by the particular gold of northern winter light, the deep orange-red of fire and forge, and — in winter nights — the Lightspill, the aurora-equivalent of the Shattered Expanse, which paints the sky in colors that range from pale green to deep violet depending on the night and the season. Ships here are built differently: reinforced for ice, lower and broader in beam, with modifications the Ember Seas captains would find bizarre. The sea here makes sounds — ice grinding, the distant blow of whales, the silence of deep frost at night — that no southern sea can replicate.
The Human Presence: The Frozen Straits are inhabited by the Järnvolk — a Norse-inspired maritime culture that predates the Age of Sail and has adapted with characteristic stubbornness to every change the Cataclysm brought. The Järnvolk are not pirates by trade (their raiding traditions are seasonal and specific, aimed at particular targets during navigable windows) but they are not always friendly to strangers, and their relationship with the old gods is direct and personal in ways that make the Tidecallers seem restrained. The Ironclad Dominion has been attempting to establish a presence in the Frozen Straits for decades, drawn by mineral deposits and the strategic value of controlling the northern passages. The Järnvolk have been resisting with considerable success.
Supernatural Character: The Frozen Straits' Cataclysm fractures are fewer but stranger. The cold preserves things that should have decayed — there are Urrathi ruins here that are so well-preserved that their machinery is still technically operational, frozen but intact. The old power that seeps from the Straits' fractures is cold and slow, manifesting in creatures that are ancient in appearance and behavior, things from before the Cataclysm that have been frozen in ice and are now, as temperatures shift, beginning to thaw.
Gameplay Identity (Expansion 2): The Frozen Straits introduce ice navigation, cold-survival mechanics, and a fundamentally different relationship with the supernatural — the power here is patient, ancient, and cold rather than chaotic and volcanic. The expansion's narrative involves the discovery of perfectly preserved Urrathi sites and the question of what happens when you find a machine that still works, deep in the ice, and you don't know what it was built to do.
The Storm Wastes (Expansion 3)
Climate and Character: Permanently dangerous. The Storm Wastes are not a region that occasionally experiences hurricanes — they are a region that is always experiencing a hurricane, or something close to one. The Cataclysm's most violent expression occurred here, and two thousand years have not been enough time for the weather to settle. The Wastes consist of a permanent rotating storm system roughly the size of a continent, within which are pockets of relative calm — the storm's eye, which moves, and smaller sheltered zones within the storm bands — where islands of remarkable richness exist.
Distinctive Visual Identity: The Storm Wastes are visually overwhelming. The storm is always present in some form — on the horizon as a wall of black cloud and lightning, or directly overhead as rain and wind and spray. The islands within the Wastes are extraordinary precisely because they exist despite the storm: lush beyond reason, sheltered by the storm's dynamics into micro-climates that produce growth in explosive abundance, their beaches littered with wreckage from every century of ships that attempted the Wastes and failed. Lightning is constant enough to have become part of the visual language — not frightening here but almost beautiful in its frequency, the sky's natural state.
The Human Presence: Few permanent inhabitants can sustain a settlement in the Storm Wastes, but several legendary pirate strongholds have existed here over the centuries, accessible only to those who know how to navigate the storm. The Storm Wastes are where legendary pirate captains go when they want to disappear, where treasures from across the centuries have accumulated in the wrecks that litter the inner islands, and where the game's most dramatic endgame encounters are set.
Supernatural Character: The Storm Wastes' supernatural nature is openly violent. The power here is not subtle — it manifests as weather phenomena with impossible characteristics, creatures of storm and lightning, and, at the heart of the Wastes, what the Tidecallers call the Maelstrom: the original wound of the Cataclysm, expressed as a permanent storm rather than a trench. The Leviathan Cult is strongest here. The Drowned Court visits but does not stay — even they find the Storm Wastes uncomfortable.
Gameplay Identity (Expansion 3): The Storm Wastes are the extreme endgame region — accessible only to captains who have mastered weather navigation, whose ships are built for punishment, whose crews are experienced enough to function in conditions that would break any newcomer. The expansion's narrative finally addresses what the Maelstrom is, what it means, and what will happen if the Leviathan Cult succeeds in using it.
The Jade Currents (Expansion 4)
Climate and Character: Monsoon-driven, organized by deep-water currents that the Jade Fleet has mapped in extraordinary detail. The Jade Currents region spans an enormous area, from tropical island chains in the south to the great monsoon sea in the north, where merchant fleets have been riding the seasonal winds between port cities for three thousand years. The sea here is organized — there are established lanes, seasonal schedules, and a complexity of maritime law that makes the Aurantine Concordat look like a provincial backwater.
Distinctive Visual Identity: The Jade Currents are visually sophisticated in ways the other regions are not. The architecture of port cities reflects centuries of accumulated wealth — tiled roofs, gardens that spill down toward the water, merchant quarters with signage in scripts the Ember Seas captain cannot read. Ships here are different: junks rigged for the monsoon winds, river-boats adapted for coastal work, ocean-going vessels whose hull forms reflect three thousand years of refinement for these specific waters. The color palette skews toward deep greens and golds, the particular blue of monsoon sky before the rains, the soft greys of early morning fog burning off over a harbor full of ships.
The Human Presence: The Jade Fleet's civilization is the primary power, but it is not monolithic — it encompasses dozens of distinct cultures connected by the trade networks the Fleet maintains. The Jade Fleet itself is more institution than government: a maritime trading organization with a navy, a diplomatic corps, and three thousand years of accumulated leverage over the sea routes it controls. The player's arrival in the Jade Currents is not as a conqueror but as an outsider encountering a world that has been doing very well without them.
Supernatural Character: The Jade Currents' supernatural element is the sea dragons — creatures unlike anything in the Ember Seas, not the mindless monsters of the shallower seas but beings of apparent intelligence and genuine motivation, who have relationships with the Jade Fleet's navigators stretching back centuries. What exactly the sea dragons are — elevated creatures, minor Old Gods, something else entirely — is one of the expansion's core mysteries. The Jade Fleet's oldest records contain information about the Urrathi that predates anything available in the Ember Seas, and the expansion's narrative is partly about what happens when the player gains access to those records.
Gameplay Identity (Expansion 4): The Jade Currents introduce a genuinely different political landscape — one where the player's Ember Seas pirate reputation means nothing, where the systems of power are unfamiliar, and where success requires learning new rules. The expansion also introduces the first genuine possibility of communicating with an Old God's agent (the sea dragons), which opens narrative threads about the Cataclysm's true nature.
The Obsidian Deep (Expansion 5)
Climate and Character: No climate in the conventional sense. The Obsidian Deep is below the sea's surface — the network of hydrothermal vents, deep-ocean trenches, and seafloor fractures that connect the world's regions through their undersides. It is the original Cataclysm wound, the place where the Urrathi's Reaching tore the world open, the place where the old gods sleep most fitfully.
Distinctive Visual Identity: The Obsidian Deep is the most visually alien region in the game. There is no sunlight here — illumination comes from bioluminescence (creatures and organisms evolved to produce their own light), from the amber-red glow of hydrothermal vents, and from the supernatural energy leaking from the Cataclysm fractures themselves (which glow a sickly green-gold, the color of the world's wound). The pressure is visible in the behavior of everything — water moves differently here, creatures move differently, and the ruins of the Urrathi's deepest sites (their submarine facilities, their power generation infrastructure, their worst experiments) are preserved in conditions where decay cannot operate normally.
The Human Presence: Almost none. The Lighthouse Keepers maintain a single station somewhere in the Obsidian Deep — how they survive there is one of their many secrets. The Leviathan Cult has attempted to establish permanent presence and paid for it repeatedly. Some of the game's most dangerous NPC enemies are entities that have adapted to the Deep — things that were once human, or once animals, or once something else entirely, and have been changed by thousands of years of exposure to the old gods' proximity.
Supernatural Character: Maximum. The Obsidian Deep is where the Old Gods actually are. Not as abstractions or theological concepts but as presences that can be sensed, encountered, and — in the most extreme endgame content — confronted. The expansion's narrative addresses the Cataclysm directly: what the Urrathi did, what the Old Gods did in response, what the wound the Reaching created actually is, and what happens when a player captain reaches the bottom of it.
Gameplay Identity (Expansion 5): The Obsidian Deep is the ultimate endgame — the final expansion, the deepest content, the confrontation with the world's oldest truth. It requires everything the player has learned across the entire game's span: underwater navigation from Expansion 1, cold-environment survival from Expansion 2, storm navigation from Expansion 3, diplomatic sophistication from Expansion 4, and the full breadth of the combat and character systems from launch. The Obsidian Deep is the answer to the question the game has been asking since the first session: what really happened here, and what comes next?
The Sea Between: Geography Notes for Designers
Islands as Characters
Every island in the Shattered Expanse should have a personality. Not a personality in the sense of "this island has palm trees and beaches" but in the sense that the island has a history, a current state, and an implied future. Islands that have been inhabited accumulate evidence of that habitation. Islands that have never been charted hold their secrets in their geology. The ruins visible on every island in the Ember Seas are not set dressing — they are the world's first sentence, asking: what happened here, and what does it mean that no one is here now?
Sea Lanes as Blood Vessels
The trade routes of the Shattered Expanse are not arbitrary lines on charts. They follow the dominant winds, the favorable currents, the safe passages between reefs. Where trade flows, civilization follows. Where trade stops flowing, civilization follows more slowly in the other direction. The player who learns the sea lanes learns the world's circulatory system — and the player who knows where a vessel's blood flows knows where to be when it passes.
Depth as Drama
The sea's third dimension is never irrelevant. What is below the hull is part of the world. Shallow waters mean reefs and shoals and the possibility of navigation error. Moderate depths mean wrecks and debris and the things that eat wrecks. Deep water means the Ley Lines run near the surface here, means the bioluminescence is active, means the chance of encountering something that belongs to the middle sea rather than the surface. And very deep water — the trenches, the vents, the Obsidian Deep's upwellings — means the old power is close and the world is thin.
The captain who never looks down is the captain who never fully understands where they are.
See also:
Factions & Civilizations — who lives in this world and how they relate
Mythology & Supernatural — the Old Gods, curses, and the world's supernatural logic
History & Timeline — how the world got to its current state
Creative Identity — the aesthetic and emotional framework this world expresses