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 wreak 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. Beyond these human conflicts lie truly dark and dangerous voids, rife with rumored terrors, undiscovered stars, and worlds of man that 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.
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 and xenos ruins are exploited, trade envoys meet with heathen lords, and colonies are attempted upon sheltered worlds. These efforts have showered wealth and fame upon the fortunate and made corpses of the rest: the gateway to the Expanse is littered with broken vessels and tales of the vanished.
Beyond the more widely-reported regions of the Koronus Expanse, past deeps beset by pirates and dread xenos, lie many worlds and strange phenomena that 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 decetiful Eldar, or the ancient myths of heathen worlds given over to darkness for millennia uncounted. Such areas are often labeled with no more than “Here be monsters” on ancient charts, and are widely viewed as the destinations of only the foolhardy or insane.