Lightrim

Lightrim is a former Imperial civilised world that served as the Adeptus Astartes Homeworld of the formerly loyalist Sanctors of Lightrim Space Marine Chapter. Located somewhere near the hellish realm of the Eye of Terror in the Nosgothica Sector in the northern Segmentum Obscurus. Following their corruption by to the corrupting influence of the Ruinous Powers, the once proud Chapter wholly dedicated themselves to the Dark Gods, and their world was purged during the Second Campaign of Damnation.

Early History
During the second century of the 36th Millennium, though Imperial records of events during this strife-torn period are notoriously ambiguous and difficult to uncover. Fragmentary records gleaned from long lost data-vaults speak of a foreboding time when there was a sudden rise in the number of daemonic incursions. A number of Chapters were created to help stem the tide of the daemonic threat. Many of these Chapters were placed at strategically vital points, throughout multiple systems, surrounding the Eye of Terror to guard against this dire threat. Along with the Sanctors, other Chapters such as the Invokers and the Relictors are also believed to have been created at this time.

The newly incepted Sanctors of Lightrim became sentinels over the worlds of the Nosgothica Sector located to the galactic north of the Segmentum Obscurus, to guard against both Traitor Legion incursions and daemonic attack. Claiming the world of Lightrim as their Chapter homeworld, the Sanctors built their fortress-monastery, the ' Light of Truth ', upon the planet's tallest mountain range. An exceptionally monastic Chapter in character, the Sanctors were known for being dedicated to the scholarly arts as to the ways of war.

Current Status
Where the Sons of Damnation's current Chapter world is exactly located is unknown, but it is assumed to be a Forbidden World rumoured to be located within the inner rim of the hellish realm known as the Eye of Terror. Their former homeworld of Lightrim was thought to be a verdant Civilised World. The native flora of this lush world was known to grow with such virility that only the vast plateaus that pierced the evergreen canopy were free from their touch. However, the corruption of the Sons of Damnation unleashed the fell powers of Chaos, which slowly poisoned the citizens of Lightrim, body and soul, until they were wholly changed into foul subhuman Chaos Spawn. Following the Imperium's vengeful purge, the once-verdant world became a benighted realm of blackened forests dotted by the empty shells of once great dead cities. As a result of the Chaos corruption of the planet, the dead do not rest easily beneath the world's tainted soil. Lightrim was declared Perditas ('Forgotten') by the Inquisition.

Fortress-Monastery
When the Sactors first claimed Lightrim as their Chapter homeworld, they built their mighty fortress-monastery. Forged from the tallest peak, known as Mt. Zo-Kalar, the Light of Truth was an impressive fortification, rising hundreds of metres above the verdant valley of Lightrim's northern continent, where the planet's capital city of Gloryrim was located. The Light of Truth was built into the heart of massive mountain, taking advantage of its natural defence. Deep shafts cut into the mountainside conceal potent defence lasers, missile silos and macrocannons, capable of blasting apart an aerial assault or even orbital spacecraft. The monastery itself comprised dozens of ramparts, watchtowers and bastions. The monastery also incorporated powerful shimmering void shields which enveloped the entire structure to ward off orbital bombardments or assaults from the ground. The fortress-monastery was riddled with subterranean chambers, some of them enormous assembly grounds and sparring arenas, others tiny cells or shrines to heroes whose inscriptions were all that remained of them in the Chapter's memory. Natural volcanic tunnels had been enlarged to form the interior of the fortress, each constructed with a mind towards defending against a ground invasion. Following the corruption of the Sanctors, the once noble citadel became known as the Master's Domain - a foul and benighted place, as corrupt and twisted as the Astartes that dwelled within. During the final assault by loyalist forces, the Sons of Damnation purposely overloaded the citadel's powerful void shield generators, and the fortress-monastery catastrophically self-destructed.