The Feral World of Orbiana lies at the spinward extent of the Severan Dominate, representing the last human-settled world along the Calixis-Scarus Warp conduit before that twisting route plunges into the benighted depths of inter-sector Wilderness Space. Orbiana itself is a wild, savage world of raging storms and unpredictable weather fronts, its native human population existing in a feral, nigh atavistic state. Orbiting the world is a massive defence platform, its plasma generators cold and its capital-scale weapons staring unblinking in the deep void.
Though unconfirmed, it is thought that the platform must have been towed out past the Periphery in centuries gone by as a long forgotten plan to defend the Calixis Sector against some now extinct threat. Perhaps it was forgotten or deemed that towing it back was not worth the vast effort it would surely require, but whatever the truth, it has orbited Orbiana ever since. Recently, Duke Severus XIII has ordered the station restored, though those few Adeptus Mechanicus Tech-adepts that still serve him have yet to succeed in doing so.
Orbiana has seen numerous Ork attacks throughout the course of the war on the Spinward Front, but it is too far from the Imperium's territory to come under direct assault from that quarter. Nevertheless, several highly-placed members of the Spinward Front High Command have expressed the opinion that an assault from the Dominate's spinward flanks might crush the Secessionists once and for all.
It is probable that these planners have no knowledge of the Orbiana defence platform and, were it to be restored to operational status before an assault was launched, the attackers might find themselves facing a well-prepared and potent defence where they least expected to discover it.
- Only War: Core Rulebook (RPG), pp. 346-348
- Only War: Enemies of the Imperium (RPG), pp. 8-31