“Lo, I see that which is beyond. I see the faces of pale moons and the fire of lost stars. I see the void un-walked and the waiting dark. I see the void that is my home and to which I return with hope and fear.”

–reputed words of unknown Rogue Trader departing Port Wander

The Koronus Expanse is the name given by Imperial authorities to a dangerous unexplored region of the Halo Stars beyond the Calixis Sector. The Expanse is accessed through the Koronus Passage, a treacherous but navigable route through the great warp storms that bar passage to the Halo Stars beyond the way station of Port Wander. As is true of the Calixis Sector itself, the Expanse was untouched by the God-Emperor’s Crusade many millennia ago---and so it is a realm of fearsome xenos, treasures beyond imagining, heathen worlds of men, and the echoes of ancient doom.

The Koronus Expanse in the 41st Millennium is a scattered, partly explored region containing a few young colonies and vast natural wealth still barely exploited. Rogue Traders vie with one another for known resources, heedless of lives lost in the pursuit of riches, while a tentative attempt at Imperial colonization follows in their wake. Drawn by the flow of wealth, pirates and servants of the Dark Gods have also slipped into the Expanse, eager to cast destruction upon the works of the God-Emperor’s faithful, living by what they wrest from dead hands, while the Expanse itself holds many secrets and native inhabitants no less dangerous.

For centuries, Rogue Traders have braved great evils and the treacherous warp to venture into the Koronus Expanse, but their efforts have barely begun to uncover its secrets. Footholds have been built close to the few semi-stable warp routes into the area. Here, resource-rich worlds are exploited, xenos ruins excavated, trade envoys meet with heathen lords, and colonies are attempted upon sheltered worlds. This effort has been enough to shower wealth and fame upon the fortunate---and make corpses of the rest. The gateway to the Expanse is littered with broken vessels and tales of the vanished.

Beyond these human conflicts lie truly dark and dangerous voids, rife with rumored terrors, undiscovered stars, and worlds of men who have never known the God-Emperor. There are no defined warp-routes, no safe ways through the swirling empyrean. These regions hold the fearsome Ork, the treacherous Eldar, and strange ruins that lie beneath the light of dying stars.

The warp space of the Koronus Expanse is treacherous and unknown in the main, and the partially explored regions of the Expanse are islands of Imperial activity amidst a vastness of danger and mystery. Navigating is a far cry from traversing the established warp routes of the Calixis Sector. Most of the Koronus Expanse is known to the Imperium only though legend, revelation, and hearsay. The Rogue Trader who ventures into this unknown risks his very soul upon the talent of his Navigator, and on the quality of what little information he has gleaned from those gone before.

Beyond the partly explored regions of the Koronus Expanse, past deeps beset by pirates and dread xenos, lie many worlds and strange phenomena which exist as the stuff of dark legend. Some of these uncharted stars were visited by a single Rogue Trader whose tales are doubted or dismissed by rivals as outright lies, while others are known only from dubious and apocryphal sources such as Thulean data-vaults recovered from Dolorium’s voids in 741.M41, or the infamous prophetic visions of the Seven Witches of Footfall. Other fragments of contradictory lore relating to these dark zones are culled from even more untrustworthy sources, such as the muted astropathic whispers overheard on the warp’s twisted eddies, the falsehoods of the deceitful Eldar, or the ancient myths of heathen worlds given over to darkness for millennia uncounted. Such areas are labelled only as “Here be monsters” on ancient charts, where only the foolhardy or insane would venture to seek their destiny.

There are no absolute truths for those exploring the Expanse, merely the whispers and misconceptions of men, the legends and fragmented histories of things that should, by all rights, be impossible, or at the very least, highly improbable. That is, at the core of it, the nature of the Koronus Expanse---a place of impossible things, some wondrous and others terrible, a graveyard of dead gods and the resting place of slumbering horrors amidst unimaginable treasures and limitless opportunities for glory. Great men and women have given their lives to see what the Expanse holds, while others have found their sanity shattered or once-noble intentions twisted by what they find. The lucky and daring few who have come back more or less intact bring with them tales that do nothing but inspire the next generation of daring explorers. And so the cycle continues, and will continue, as long as people exist who see danger as merely the cost of opportunity.

A great many things are afoot within the Expanse, from the politics of Port Wander and Footfall, to the fates of distant colonies that shudder beneath the light of tainted stars and dread storms, to the things that lingered in the darkness before Mankind ever ventured beyond the Maw, and the other forces that have come to exploit the wonders and horrors that lay in wait. Presented here is a small selection of those things, legends ranging from the epic and world-shattering, to the tall tales of voidsmen told in dank taverns over cups of dubious liquor, and the footnotes of ancient historians whose works gather dust for generations.

The Great Warp Storms of the Halo MarginsEdit

“Calixian history is littered with footnotes describing the lost and the dead who braved the Great Warp Storms beyond the worlds of Saint Drusus.”

–from The Voids, scribed by Tarsimus of Archaos

On the rimward margins of the Calixis Sector boil vast warp storms that have since ancient times barred passage into the Halo Stars. This barrier of raging tempests has claimed the lives of many who would dare to find new passage to the unexplored expanses. They ebb and flow with a ferocity and maliciousness that can lure even the most seasoned navigator to destruction in a sudden rending surge. Though these warp storms are referred to as a group, they are in fact an amalgamation of individual warp storms that clash, overlap, and occasionally consume one another. Passage through this mass of tempests is almost impossible outside a few stable routes that run through the storms like narrow threads of calm. Some storms have persisted for long enough that they have acquired names of infamy amongst those who travel and navigate the Sea of Souls. Of these, the most famous are the Void Dancer’s Roil and the Screaming Vortex, which bracket the stable passages known as the Maw like daemon sentinels at the gates to a waiting hell.

The Void Dancer's Roil is a mass of subtly sliding drifts and beguiling currents in the warp that can lead the most seasoned navigator astray and carve apart the hulls of ships that dare their tides. It is said that ghost-ships have been sighted drifting amongst the Void Dancer’s Roil, their hulls as pale as carved stone.

The Screaming Vortex is a boiling mass of warp turbulence and vortices that clash and grind against one another with unceasing fury and power, giving rise to a constant psychic wail that can be perceived by those sensitive to the flow of the warp. It is this dread wail that gives the warp storm its name. The character of the Screaming Vortex is that of a raging beast whose teeth clash and gnaw in a never-ending search of food, and it is said by the void born that it has claimed entire fleets to satiate its endless hunger.

Nesting within or beside the Screaming Vortex and the Void Dancer’s Roil are other lesser warp storms whose nature is permanent and distinct enough that they have acquired their own infamy and doom-laden titles. Some navigators who have strayed within or to the edge of the great storms whisper of the Deathveil as a strange cascade of unnatural beauty that will draw the mind of the unwary to within its soft and silent embrace never to return. Old voyagers into the Halo Margins of the Calixis Sector exchange strange stories of the pocket of stillness within the fury that they name the Whispering Storm, where the fingers of the dead caress the hull and forgotten voices whisper inside the minds of the living in voices of crackling static. These strange storms within the warp, and many others beside, all whirl and dance together and so create a wall within the sea of souls that cannot be crossed except by a rare few stable warp routes. The greatest and most easily navigated of these is the Koronus Passage, or “the Maw” as it is more often called, which passes through the Great Warp Storms and into the dark unknown of the Koronus Expanse.



“The void is like a vast ocean. Those worlds you live on are naught but islands, around which circle the predators of the deep.”

–Caeluthin Baharrudor, the Stormchaser

There are a countless worlds in the Koronus Expanse. Some have felt the tread of humans for millennia, while others wait in the dark of space to be discovered. Though the Koronus Expanse has been open to the Imperium for a millennia, and known humanity for countless millennia before, it is still ill-explored and largely-undiscovered. Even the worlds charted by explorers still hold many secrets closely. Some are famous, such as the conflict-torn and resource-rich world of Lucin’s Breath. Others, such as the Serpent's Cradle, are unknown to all but the most accomplished Rogue Traders. All, however, have opportunities for enterprising Explorers, and dangers waiting to spring upon the unwary.

Space Stations and ShipsEdit

Power GroupsEdit

“Anyone who looks upon a star and thinks himself the first to do so is a fool. Every planet, moon, or glittering sun is the grave of untold races and the slumbering tomb of secrets lost to the passage of time.”

–words attributed to Rogue Trader Solomon Haarlock

The Koronus Expanse is a gulf of darkness in which the few facts known by humanity stand like guttering candles. Within its vast bounds wait worlds and secrets that it would take generations of explorers to discover, and within these vast gulfs of the unknown and uncharted dark other things move and plan with inhuman minds and soulless purposes. From the long-dead makers of the Halo Devices to the treacherous Eldar, many other powers have a claim or interest in the Koronus Expanse, and each has its own purposes and knowledge that drives it to act. These motivations frequently bring them into contact with the Rogue Traders who are but the youngest of their kind to walk these stars.

Threats in the ExpanseEdit

“The only problem with these xenos scum is that they do not acknowledge our Emperor-given right to rule these stars.”

–Rogue Trader Hadarak Fell

Beyond the Imperium’s borders, the untamed wilds of space hold myriad threats and infinite dangers. Few are more treacherous and more resilient, however, than the threat of the xenos. Long forgotten alien empires lurk trapped within the darkest reaches of the Koronus Expanse, waiting to for some unlucky Rogue Trader to stumble across them. Deadly as they are, however, they can at least be conquered by humanity’s superior knowledge of star travel, righteous hatred, and nigh-infinite resources.

Worse are the races who have mastered the secrets of interstellar travel. The destructive Ork hordes, the mercenary Kroot, the capricious Eldar, and the ravenous marauding Rak’Gol are all threats within the Expanse that wise Rogue Traders heed. Of course, they are not the only dangers one may face. Myriad human interests have travelled into the Expanse in the wake of Rogue Traders, and many are just as likely to become an Explorer’s foe as an alien warship.






Followers of False GodsEdit

There are worlds waiting to be discovered within the Koronus Expanse that are inhabited by people who have fallen to the worship of false gods - gods which are but a mask for the Ruinous Powers. Proud and decadent civilizations build temples to the Dark Gods and bind their societies together with sorcery, terror, intrigue, and atrocity. On some planets, they may worship the glory of Chaos as a pantheon of gods and divine servants, the dark reality of their beliefs cloaked in strange names and mystery. Others may have fallen into the embrace of worship of a single Chaos God, becoming a world in which war and bloodshed is the bedrock of existence, or one which has evolved an elaborate social and political hierarchy around which intrigues, lies, and secrets move like poison. Where these worlds may be or what devilries they harbour are yet to emerge from the dark unknown of the Expanse, but they are there waiting like serpents in long grass. Were such a world to be discovered, all true servants of the Emperor would destroy its people and the lie of its gods completely and utterly, lest its poison and lies spread.

The Fate of Colony XK-119Edit

In the closing months of the 40th millennium, Rogue Trader Kinker Drub received the Warrant of Trade, and along with it the obligation to reclaim Colony XK-119, a small facility on a satellite of an unnamed gas giant several weeks’ travel into the Koronus Expanse. The world was of little real value to the Imperium, but it had been won from an alien race that had been discovered there, and human blood had been spilt upon its soil. Therefore, when the previously assumed extinct aliens returned in force and retook the world, Drub was tasked with crushing them once and for all.

Attached to Drub’s own forces was a composite Adeptus Astartes task force, consisting of a dozen squads drawn from as many different Space Marine Chapters. Drub had the authority to determine where the Space Marines would fight---the Astartes themselves would determine how. Arriving at XK-119, the flotilla was immediately attacked by the alien vessels---which, having never been encountered before, made for a formidable enemy. Drub’s vessels suffered some damage, but during the fight the Astartes were able to close on what was assumed to be the xenos flagship and affect a boarding action. The aliens were unable to repel the boarders, and the entire xenos command cadre was slaughtered, causing the remaining alien vessels to disengage and withdraw.

Drub then accompanied the Space Marines to the colony itself and discovered there a scene from nightmare. The colony, it transpired, had been built within the crumbling ruins of an alien city, and the colonists had uncovered, and attempted to operate, items of alien technology. Evidently, the former residents of the world had not been the last of their race, and others of their kind had somehow been summoned by the colonists’ tampering.

Drub determined to track down these xenos, reasoning that they were possessed of highly advanced technology that would be of great value to certain groups within the Adeptus Mechanicus. The Space Marines agreed to track down and destroy the aliens to maintain the honour of the Imperium, thereby punishing those who would dispute humanity’s right to dominate the stars. Drub and his task force of Astartes were never seen by any human again.

Unique Equipment (Temporary)Edit

Fractal Blade

These rare swords are made from a diamond-like living crystal, each blade harvested from an unknown planet in the Koronus Expanse, its location a carefully kept secret by the Rogue Trader who sells them. When struck (such as in a Parry action) small slivers flake off, and the blade emits a shrieking sound akin to nails on a chalkboard. The crystal constantly grows and replaces shards as they are struck off, keeping the edge sharp at all times but also meaning it must be frequently used lest it become dull and blunt. Each sliver is a fractal seed, a replica in miniature of the full sized blade. Indeed, if planted back on its home world it would grow into a new sword.

Melee, 1d10+1(+SB), R, PEN 7, Power Field, Balanced, WT 1kg, Extremely Rare

Ghost Sword

Most races have some sort of long bladed item in their armoury and many Explorers make good use of those they find that take their fancy, either as trophies or for more practical reasons. Many have been linked to known alien cultures, but some resist clear identification. “Ghost Sword” is the name given to a common style found on many newly explored worlds in the Calixis Sector and beyond, often amongst the remains of ancient battles. This deadly sword is clearly of fine but alien craftsmanship, lightweight but stronger than any Imperial steel. Despite warnings from the Adeptus Mechanicus and Inquisition, some bold Rogue Traders wear these weapons in open scabbards to show off their independence and prowess as explorers. The ghost Sword adds an additional +5 bonus to the Parry action for a total of +15.

Melee, 1d10+3, E, PEN 6, Power Field, Balanced, WT 1kg, Extremely Rare