Remus Ventanus - Uriel Ventris and the Tomb of Ventanus: As a young child, the future Captain of the Ultramarines 4th Company, Uriel Ventris, climbed an area known as the Dragon's Gullet on Calth -- an area where the children of that world would climb high in order to paint a picture of a dragon on the sheer cliff face. This was one of many games, dares and contests of strength, speed and endurance played by the boys and girls of Calth in preparation for the selection games when warriors from the Ultramarines would judge who was worthy to be taken to Macragge and inducted into the Chapter.Climbing higher than anyone before him (or since), after painting his dragon Ventris saw a cleft in the wall that led deeper into a cavern. He followed the lightless tunnel that twisted into the rock for hundreds of metres until it ended at a compartment hewn from the rock nearly ten thousand years earlier by artificers with great skill and even greater determination.In the centre of the cavern was a building of pale, polished marble -- a magnificent structure, topped with a glittering dome apparently fashioned from a single vast sapphire. Each facade of the building was reached via a triumphal set of steps carved from the rock of the cavern floor, and entrance was gained through vast porticos supported by pillars as thick as the legs of the largest Mechanicus battle engine. Each pediment was carved with colourful murals that had survived the passage of centuries without the lustre of their imagery diminishing.The murals were broken up into panels, each depicting a noble Ultramarines captain leading his warriors in battle against wicked, red-armoured foes. As a child, Ventris hadn't fully appreciated the significance of the hidden structure, for it was a tomb, the resting place of a great hero -- the lost tomb of Remus Ventanus. The Saviour of Calth.Though a portion of its supporting facade had collapsed, the great gem of a dome remained intact, its roof unbowed. The interior floor plan of the tomb was circular, laid out like a grand amphitheatre or council hall. Though instead of steps or seats, the tiers around the central open space were for the dead.Hundreds of stone sarcophagi were laid out in concentric circles around the central floor of the tomb, each one a member of some lost Chapter of the Ultramarines back when they were organised as a full Space Marine Legion. In the centre of the tomb, directly beneath the dome's cupola was a gleaming sarcophagus of black marble, machine-finished and miraculously free of dust after centuries of isolation. Bare of ornamentation apart from a silver plaque bearing the name of the warrior entombed within -- the final resting place of Captain Ventanus of the Ultramarines Legion.In 999.M41, the Iron Warriors Warsmith Honsou discovered the secret of the Daemon Prince M'kar's imprisonment, and after finding and conquering the star fort Indomitable, set the daemon free to serve as his ally in a new Chaos campaign against Ultramar. Possessing a desecrated Dreadnought shell to remain in the Materium, the newly rematerialised M'kar bound the Indomitable to a Warp Gate and called forth a huge army of daemons, who along with others under his command, he named the "Bloodborn".During the Invasion of Ultramar, M'kar sent Honsou to Calth in order to destroy Ventanus' tomb. The daemon had not elaborated much when it had told Honsou that this shrine was to be cast to ruin, only that he was to ensure that the body of Ventanus and all his wargear were consumed utterly.Investigating the contents of Ventanus' sarcophagus, Honsou found the Shard of Erbus and took it, realising the real reason why M'kar had sent him to destroy it. He was deathly afraid of the vile weapon. As Honsou made to leave, he encountered his old nemesis, Uriel Ventris, and his token force of Ultramarines. The Iron Warriors and the Ultramarines had both waited a long time for this reckoning.In the midst of the battle that followed, Ventris' life was saved by a spectre from the past -- a giant burning with azure light that spoke of ancient heroism and noble deeds of valour beyond anything Uriel could comprehend. His armour retained traces of its former allegiance, gold trims, a pale eagle on the shoulder and a faded, barely legible, inverted omega symbol. In the centre of the "U" was the symbol for a Space Marine Captain, but it was old, ancient even, a standard of rank insignia that had not been used for ten thousand standard years.In that moment, Ventris realised this was none other than the spectre of Remus Ventanus himself. The figure leaned into him and with a ghostly whisper imparted a word or a name. Initially it meant nothing to him, but when the figure pressed the dagger into his hand, Uriel realised what he had been told. He understood, feeling a potent sense of duty discharged, a burden and a responsibility passed on, as though the shade had been waiting for this since the moment of its death.Ventanus had imparted M'kar's true name -- Maloq Kartho. Chapter Master Marneus Calgar would use this crucial piece of information when he faced M'kar for the final time. In the battle, Captain Ventris tossed the Shard of Erebus to him at a critical moment, and the Chapter Master utilised the corrupted dagger to finally kill Maloq Kartho -- destroying the essence of the daemon utterly -- finishing what Captain Ventanus had begun ten millennia earlier.