Primaris Space Marines - Rubicon Primaris: The induction of the Primaris Marines into the Adeptus Astartes was not an easy process by any means. The Chapters of the Space Marines are generally arch-traditionalists, and some are conservative in the extreme, having upheld the same warrior traditions for thousands of Terran years.Of course, the express command of Roboute Guilliman as the lord commander of the Imperium and Imperial Regent eased the transition into the new era.For the Ultramarines and the vast majority of their Successor Chapters, the word of their risen primarch was good enough, and many Chapters welcomed the Primaris battle-brothers gladly.But there were those especially secretive or willful Chapters who saw the incorporation of the Primaris Marines into their ranks as a dilution of their gene-stock and a betrayal of their long-held culture.Some amongst the Adeptus Astartes suspected that the Primaris Marines, being stronger, more durable and closer in blood to the primarchs themselves, represented the obsolescence of the Firstborn Astartes. No amount of reason -- of pointing out that what the Primaris offered in raw ability, they lacked in experience and versatility -- could salve the spiritual wound dealt by the sight of the newcomers wearing their Chapter heraldry.The Primaris Marines of the Ultima Founding had been swiftly inducted into brotherhoods that the incepted aspirants of yesteryear had given everything they had to join. Questions, heavy with the weight of Mankind's destiny, hung in the air.Would the Primaris Marines ultimately render the traditional Firstborn Space Marines extinct? Would the identity of each Chapter's homeworld be diluted, with so many thousands of new recruits sourced from the stasis vaults of Mars?And was it possible for a Firstborn Space Marine to be transformed into a Primaris, inheriting the benefits of Adeptus Mechanicus arcanoscience whilst retaining his personality and experience?This last question had been raised in Adeptus Astartes Chapters across the galaxy. It was a query Marneus Calgar, Chapter Master of the Ultramarines, had asked of Belisarius Cawl himself, and had discussed with those of his fellow Chapter Masters he was able to meet in person.Debate raged as to whether such an act was even possible without having deadly consequences for the recipient -- for data that Archmagos Cawl had already amassed on the subject suggested there would be a 61.6% failure rate at such a transformation until the process could be perfected, which would take time. Then there was the moral concern of whether the process should be attempted at all.The dilemma proved divisive. There were those who claimed that this was the ultimate destiny of all Adeptus Astartes, while from other quarters came whispers of rejection, even mutiny, at the prospect.The lords of the Ultramarines came to the conclusion that to ease the transition from centuries of Imperial tradition to a new order, the theoreticals of that raging debate needed to be put into practice. It was Marneus Calgar who stepped forward as the first test subject from the ranks of his storied Chapter. It was a process he did not survive -- though like his primarch before him, he was to rise from the threshold of death once more.The operation to transform Calgar from a traditional Space Marine into a Primaris Marine was conducted in an auto-sterilised med vault. Thick with the tang of counterseptic and crowded with elaborate medical servitors, the room was dominated by the great marble slab at its centre, artfully carved with runnels to collect the copious streams of blood that would result from the procedure. The surgery was to be extensive and agonising, a fact Marneus knew well from Cawl's tediously thorough descriptions of the process.A Primaris Marine is gifted three new gene-seed organs in addition to the nineteen originally grafted, sutured and chemically implanted into an aspirant Space Marine.These are the Magnificat, which is buried deep in the brain to stimulate growth and to intensify other organ functions; the Belisarian Furnace, which releases a burst of synthesized hypersteroids and corticostimulants when a mortal blow is dealt so the Primaris Marine may fight on; and the Sinew Coils, cable-like lengths of durasteel that encase every tendon and sinew in a metallic sheath that gives tremendous resilience and strength.During the implantation of the Primaris organs, Marneus Calgar was cut open from crown to heel. His ribcage was cracked apart and -- at the climax of the procedure -- his physiology suppressed to the point that his life slipped away. Choirs of cyber-cherubs sang blissful, overlapping requiems, swaying their aspergillums so that sacred incense might guide Calgar's soul back to his body.The corpse lay in state, its flesh rent and open to the air, for what seemed to those watching like an age. Ten long solar minutes ticked past, then twenty. Skull-faced surgeons clicked and muttered and stabbed at the Chapter Master's tortured flesh. Those around the periphery of the Apothecarium theatre held their breath in dread.Then, with his wounds stitched closed by a thousand jabbing needles and his mighty hearts electrified to beat once more, the newly forged Marneus Calgar was brought back to life. He broke his bonds with a strangulated, blood-flecked roar, stumbling to life as his newly-implanted Belisarian Furnace brought him to instant battle readiness.Calgar had clawed his way back from beyond the brink of death, and in doing so, he had shown his Chapter and all Space Marines that the transformation was possible.The Rubicon Primaris had been crossed, and a new path opened for the Space Marines. In honour of his courage, the Ultramarines thereafter called the procedure the "Calgarian Rites."