Nathaniel Garro - Finding Euphrati Keeler: In downtime between his missions for Malcador and the Knights-Errant, Garro followed up on rumours of the location of Euphrati Keeler, the former Remembrancer he had helped to rescue from the Vengeful Spirit at Isstvan III who was now regarded as a Living Saint by the devotees of the Lectitio Divinitatus.Keeler, whose miraculous abilities to defeat Daemons and influence people had raised suspicions that she was some form of Renegade psyker among the Sisters of Silence, had been released from the Somnus Citadel on Luna after no evidence of psychic ability had been found. Once on Terra, she spent her time spreading the belief that the Emperor was a god and growing the nascent cult of the Lectitio Divinitatus.While searching for Keeler on Terra's Riga orbital plate, Garro met Katanoh Tallery, a scribe of the Imperial Administration who in the course of her work had discovered that starships and other crucial strategic supplies were being secretly siphoned away from other projects to prepare Terra's defences and covertly delivered to Titan, the moon of Saturn under the operational codename of "Othrys."Tallery feared that the mysterious shipments were part of a plot by Traitors embedded in the bureaucracy of the Departmento Munitorum to somehow aid Horus' cause in advance of the coming Siege of Terra. Garro believed her suspicions to be true due to her utter devotion to the God-Emperor and His growing cult.Together, the scribe and the Knight-Errant boarded a derelict starship intended to be used as raw material to build a new fortress-monastery on Titan. They managed to make their way to various construction sites on the large moon where they discovered that strange, psychic-based weaponry was being shipped to the site. They also found transports arriving bearing wounded civilians and Imperial troops from the fall of the colony world of Mertiol to Horus' forces.Determined to discover the truth behind what was happening on Titan, the pair fought their way through the security forces present to the very top of the newborn fortress-monastery, where to their shock they discovered Malcador the Sigillite already there waiting for them.The Regent of Terra revealed that what was happening on Titan was not part of a conspiracy by the Traitors, but the culmination of a secret new project authorised by the Emperor Himself that was intended to ensure that Humanity would still be able to combat the threat of Chaos long after the Horus Heresy had ended.Tallery found it difficult to bear the knowledge that Chaos would continue to threaten Mankind even after the end of the great civil war that now engulfed the Imperium. To end her threat to the security of the project, Malcador ordered Garro to execute her and put her out of her misery.Garro refused, and rebelled against the sheer cruelty of the order against someone who was a proven servant of the Emperor. Malcador relented and came up with another solution that would make use of bot Tallery's knowledge as well as her proven skill as an adept. She was taken into the Sigillite's confidence concerning the true scope of the project on Titan and made the project's curator-adepta primus, the Imperial bureaucrat in charge of completing the new facilities on Titan.Garro's next mission for the Sigillite took him to the world of Nolec Trimus, where he fought a dragon-like Daemon that fed on Human blood. Facing only Garro, the Daemon proved unwilling to attack and seek to possess him without the reward of more mortals to prey upon. So Garro waited for Imperial reinforcements to arrive, finally killing the beast when it took the bait alongside his fellow Knight-Errant and member of The Seventy, the former Death Guard Astartes Helig Gallor.Garro returned to Terra and once more took up his quest to find Keeler. In the course of his investigations he discovered a remote site called Salvaguardia where a group of the Lectitio Divinitatus faithful had been massacred by unknown assailants. Garro also met First Captain Sigismund of the Imperial Fists while going over the site, who revealed that he had encountered Keeler who had also awoken his own growing belief in the divinity of the Emperor.In truth, Keeler was being hunted by the Vindicare Assassin Eristede Kell, who had once been part of an Execution Force sent by the Assassin clades to kill Horus on the world of Dagonet early in the Horus Heresy.Kell had survived the assault, but had eventually been taken captive by Horus. His mind broken by years of isolation aboard the Vengeful Spirit while he waited for another chance to kill his target, Kell proved to be easy to turn to the Warmaster's service. Kell had been returned by the Traitors to Terra alongside the covert Alpha Legion operative Haln and ordered to find and kill Keeler.Aware of Keeler's central role in the growing cult of Emperor-worship, the Warmaster hoped her death would unleash mass religious hysteria, further damaging Terra's stability as the Traitor forces closed on the Sol System.It was the Assassin and the Alpha Legion operative who had massacred the faithful at Salvaguardia, where Keeler had been known to preach, and then tortured the survivors for information on the Living Saint's whereabouts.Eventually, both the Traitor operatives and Nathaniel Garro managed to track Keeler to Terra's Hesperides orbital plate where a group of Emperor worshippers were being held as prisoners for their violation of the Imperial Truth.The Traitor operatives infiltrated Keeler's group of the faithful, but when they moved to kill the Living Saint, Garro intervened, cutting Haln in half with his great sword Libertas and then killing Kell before he could unleash the Daemon-possessed weapon Horus had given to him to carry out his task.During the battle, Keeler continued to demonstrate miraculous powers, including the ability to share visions of the future, heal wounds, and stop time to communicate with others.To protect Keeler from any further attempts on her life, Garro handed her over to the custody of Malcador the Sigillite. Just before she was taken away by the Knight-Errant Vardas Ison, Keeler told Garro that his hand would free her when the time came.Keeler was placed within a prison below the Imperial Palace complex, where she was guarded by the troops of the Imperial Army regiment known as Malcador's Own.She would be visited several times there by Garro in the years that followed along with her old friend the former Iterator Kyril Sindermann, who somehow was able to regularly infiltrate the complex. Garro sought comfort and reassurance from the Living Saint, and he visited her for the final time just before nine Knights-Errant were chosen to serve as the founders of the Grey Knights.