Credos - History: The world has seen many changes in the long millennia of its existence. The structure known as the Theopticon is said to have existed upon Credos' only continental mass since before the Horus Heresy, the statues of the Emperor and the Primarchs dominating the skyline with their size and majesty.In the wake of the Horus Heresy, Credos became a world of specific importance in the Jericho Sector. As belief in the God-Emperor spread across the Imperium in the 31st and 32nd Millennia, temples and shrines were constructed to celebrate that faith, and worlds came together to share it.When the Temple of the Saviour Emperor became the official religion of the Imperium, the many priests and clerics of the Emperor within the ancient Jericho Sector embarked upon a pilgrimage to Credos, to stand beneath the gaze of the Emperor and His sons and consider the faith that they all shared.Over the course of many years, these priests resolved many disputes and came to many conclusions, determining the sector's first Imperial saints, the core tenets of faith, and the structure of the sector's dioceses and which worlds would fall within them -- in short, the entire religious landscape of the Jericho Sector.In the millennia that followed, the sector's Cardinals embarked upon a pilgrimage back to Credos once a decade, to discuss matters of politics and theology, their grand conclave being the only opportunity these powerful individuals had to all appear in the same place at the same time.However, the tradition was ended with the appointment of Arch-Cardinal Udo Asterus, who saw no need to discuss his power with those he considered beneath him, and Credos lay abandoned by all save the last generation of monks who maintained the temple.Centuries after Cardinal Asterus' demise, Credos had been all but forgotten, its existence remembered only in the works of scholars, or so it was believed by the rulers of the Jericho Sector.For reasons which even today are unclear, the Deathwatch keep a watchful eye on abandoned Credos, despite the temple there being empty but for the desiccated remains of the monks who once dwelt there as caretakers.For some five thousand standard years, the Deathwatch has maintained a vigil over Credos, employing a select group of trusted mortal serfs to maintain the temple and the arcane machinery that keeps the immense statues from collapsing.During that time, many Battle-Brothers of the Deathwatch have voyaged to Credos, some to bear witness to the visage of their ancient gene-fathers, while others confine themselves to the temple complex instead, venturing deep into the catacombs for solar weeks at a time.The first Tyranid creatures made planetfall on Credos in late 816.M41, when a cluster of Mycetic Spores bearing vanguard organisms plunged into the ocean several hundred kilometres from the world's only land mass.It is believed that Credos, being largely lifeless, is a low priority for the Tyranids compared to populous worlds like Castobel or verdant ones like Phonos.Even so, the group of Deathwatch serfs given stewardship of Credos must now contend with the likes of Genestealers and Lictors attempting to gain access to the mountain temple, slaying all they encounter to prevent knowledge of their presence reaching the hive fleet and bringing a greater concentration of Tyranids down upon them.