Nathaniel Garro

Nathaniel Garro was the Battle-Captain of the Death Guard's 7th Great Company. He was the leader of the 70 surviving Loyalist Astartes who alone of the Death Guard Legion escaped the betrayal of Horus on Istvaan III aboard the Imperial Navy frigate Eisenstein to bring word of Warmaster Horus' betrayal to the Emperor. He held to the original tenets of the Legion when many of his Battle-Brothers chose to follow the Warmaster, their traitorous Primarch Mortarion, and First Captain Typhon's decision to serve Chaos and overthrow the Emperor, installing Horus as the true Emperor to rule over the Imperium of Man.

History
Nathaniel Garro was born on holy Terra, in the small techno-barbarian state of Albia, situated in the area of southeastern Europe near what had once been known as Albania. Garro was one of the few remaining Terran Astartes of the original XIV Legion ‘Dusk Raiders’. He had been drawn up into the Legiones Astartes before men had even known the name of Barbarus. In those years the XIV Legion had gone by a different title, and they had no Primarch but the Emperor himself. They had been the Dusk Raiders, so known because of their signature tactic of attacking a foe at nightfall. Then, they had worn armour without the green trim of the current Legion. The wargear of the Dusk Raiders was the dull white of old marble, but with their right arm and shoulders coloured in a deep, glistening crimson. The symbology of the armour showed their foes what they truly were – the Emperor’s red right hand, the relentless and unstoppable. Many enemies had thrown down their weapons the moment the sun dipped beneath the horizon, rather than dare to fight them

But that too had changed. When the Emperor’s clone-sons, the great Primarchs, had been sundered from his side and scattered across the galaxy, the Dusk Raiders joined their brother Legions and their master in the Great Crusade that began the Age of the Imperium. Garro had been there, centuries past. Garro had been there as the Emperor crossed the galaxy in search of his star-lost children – Sanguinius, Ferrus Manus, Roboute Guilliman, Magnus the Red and the rest. With each reuniting, the Lord of Mankind had gifted his sons with command of the forces that had been created in their image. When at last the Emperor came to Barbarus and discovered the gaunt warrior foundling leading its oppressed people, he had located the avatar of the XIV Legion.

On the day of Mortarion’s coronation as Primarch, a good majority of the XIV Legion had been of Garro’s stock, men born on Terra or within the confines of the Sol system, but slowly that number had dwindled, and as new recruits joined the Death Guard fold they came only from Barbarus. Now, as the Thirty-First Millennium turned about its axis, there was only a comparative handful of Terrans in the Legion. In his blackest moments Nathaniel imagined a time when there would be none of his kinsmen left among the XIV, and with their deaths the traditions of the old Dusk Raiders would finally fade away. He feared that moment, for when it came to pass something of the Legion’s noble character would die as well.

His refusal to relinquish ancient traditions and ‘high-handed’ leadership caused a rift between himself and some of the Barbarus-borne Captains, who often referred to the staunch and reserved Battle-Captain as "Straight-arrow Garro." Many of the newer Astartes inducted from the Death Guard homeworld of Barbarus felt that before their Primarch had brought new, ‘strong blood’ to their Legion, there were many rituals and habits that knotted around the Astartes. Most had been cut away. Though some still remained thanks to the dogged adherence of men who should know better. The old ways were fading, and there were few among the senior battle-brothers of the Death Guard who deigned to keep the careworn traditions of the Legion alive. Times, and the Astartes, were changing. The slow shifting of mood had begun in the months following the Emperor’s decision to retire from the Great Crusade after the conclusion of the Ullanor Crusade, from the time that he had bestowed the honour of Warmaster upon the noble Primarch Horus. He further compounded this rift by his refusal to join the fraternity of the warrior lodges, despite being offered membership on multiple occasions.

The Death Guard differed from many of their brother Legions in the manner of the command structure and ranking, for instance. Tradition had it that the XIV Legion would never number more than seven great companies, although those divisions held far more men than those of other Astartes cohorts like the Space Wolves or the Blood Angels; and while many Legions had the tradition of giving the honorific of ‘First Captain’ to the commander of the prime company, the Death Guard also held two more privileged titles, to be bestowed upon the leaders of the Second and Seventh Companies respectively. Thus, although they held no actual seniority over one another, Captain Ignatius Grulgor of the 2nd Company could carry the rank of ‘Commander’ if he so wished, just as Garro, as Captain of the 7th Company, was known as ‘Battle-Captain’. Garro’s particular honorific dated back to the Wars of Unification, to a moment when the mark of distinction had been handed to a XIV Legion officer by the Emperor himself. He was proud to bear the honourific centuries later.

Garro possessed a patrician aspect, showing its roots from the warrior dynasties of ancient Terra, pale-skinned, but without the pallidity of his brother Death Guard who hailed from the Death Guard’s cold and lethal homeworld of Barbarus. He had old eyes in a face that, despite its oft weary countenance, seemed too young for them; a head, hairless and patterned with pale scars. In battle the Battle-Captain wore Mk IV Power Armour. On the chest of Garro’s power armour was a brass cuirass that rested there. This was a ceremonial piece that Garro wore only in combat or upon formal occasions. In tandem with the honour-rank of Battle-Captain, the decorative over-sheath sported an eagle, wings spread and beak arched, sculpted from brass as if about to take flight from the chest plate. Similarly, the rear of the cuirass had a second eagle as a head-guard that emerged from the shoulders when worn over the backpack of Astartes armour. What made this piece unique was that its eagles differed from the Emperor’s Aquila. While the symbol of the Imperium of Man had two heads, one blinded to look at the past, one sighted to see to the future, the Battle-Captain’s eagles were singular.

Great Crusade
Battle-Captain Garro was a seasoned veteran of multiple campaigns of compliance, having fought alongside other Legions and forming bonds a few select Astartes from these fellow Legions. He knew Captain Garviel Loken of the famed Mournival, when the Death Guard fought alongside the elite Sons of Horus Legion during the Krypt Campaign against the vile Orks. Garro was also close friends with First-Captain Saul Tarvitz of the Emperor’s Children. The two Astartes shared a close bond as ‘honour brothers’. There were few men outside the Death Guard that Garro would ever have given the distinction of that address (being called ‘brother’), but Tarvitz was one of them. He had earned Nathaniel’s friendship during the Preaixor Campaign and proven to him that for all the reputation of Fulgrim’s Astartes as overconfident peacocks, there were men among the ranks of the Emperor’s Children that embodied the ideals of the Imperium. In recognition of their bond, the two Astartes had a small eagle carved there by knifepoint, a sign of the battle debt they owed one another. When the two clasped each others wrists their vambraces would form the Imperial Aquila.

Towards the closing of the Great Crusade Battle-Captain Garro earned high accolades during the Jorgall Persecution, for his actions when he fought alongside a cadre from the Sisters of Silence. He was singled out by his Primarch Mortarion, who offered Garro the rare opportunity to share a celebratory drink with him. It was said that there was no toxin too strong, no poison so powerful and no contagion of such lethality that a Death Guard could not resist it. The Death Guard were known to harden themselves through stringent training regimens as neophyte Astartes, willingly exposing themselves to chemical agents, contaminants, mortal viral strains and venoms of a thousand different shades. They could resist them all. From a set of bowls was mixed and poured dark liquids into a pair of ornate goblets. The odour of the noxious chemicals is usually quite powerful. The senses of the chosen Astartes often resisted, their implanted Neuroglottis and Preomnor organs rebelling at the mere smell of the poisonous brew; but to refuse the cup would be seen as weakness. The poured distillate often contained a potent mixture of agent magenta nerve bane, some variety of sword beetle venom, and other, less identifiable compounds. The cups were Mortarion’s, and in each battle where the Death Lord took the field in person, he would select a warrior in the aftermath and share with that man a draught of poison. They would drink and they would live, cementing the unbreakable strength of the Legion they embodied.

Mortarion knew Battle-Captain Garro frowned upon such things as the cups, but he explained to him that honours and citations were sometimes necessary. Warriors must know that they are valued. Praise from one’s peers must be given when the moment is right. Without it, even the most steadfast man will eventually feel unvalued. Mortarion talked to Garro privately, trying to gauge the Battle-Captain and figure out where his loyalties truly lay. The Primarch wanted to ensure that Garro would be loyal to him and their righteous cause when the Warmaster launched his campaign to usurp the Emperor and topple the corrupt Imperium. Mortarion also wanted to known why the Battle-Captain eschewed membership to the warrior lodge within their Legion. Garro felt that as Astartes, they had been set on a path by the Master of Mankind, tasked to regather the lost fragments of humanity to the fold of the Imperium, to illuminate the lost, castigate the fallen and the invader. They could only do so if they possessed truth on their side. If they did not do this openly then he had doubt that the XIV Legion would eventually expunge the fallacies of gods and deities, but they could not bring the secular truth to bear if any of it was hidden, even in the smallest part. Only the Emperor could show the way forward. Garro felt that these lodges, though they had their own worth, were predicated upon the act of concealment, and he would take no part in it. Though disappointed by the Battle-Captain’s point of view, Mortarion still hoped to turn Garro to their cause. He appointed the Battle-Captain as his equerry, taking him to an important conclave aboard the Warmaster’s flagship, the Vengeful Spirit, to discuss the upcoming coming campaign in the Istvaan System. The Primarch hoped to sway Garro’s loyalty towards the Warmaster’s cause.

Istvaan III
The Garro’s 7th Company fought in concert with Emperor Children’s elite 1st Company against traitorous forces on Istvaan Extremeis, the outermost planet within the Istvaan System. Whilst fighting against a powerful psyker known as a Warsinger, Garro sustained serious injuries; crushing damage to his torso, arm as well as the loss of his right leg from the mid-thigh down. He was only saved from certain death by the timely ministrations of an Apothecary from the III Legion Emperor’s Children – Chief Apothecary Fabius. His leg was eventually replaced with an augmetics leg of excellent quality. Garro was livid, feeling his anger surge each time the new leg made him limp. The minute gyroscopic mechanisms in the limb would take time to learn the motions and kinetics of his body movement, and until they did, he would be forced to walk as if lame.

The Legion’s Apothecaries had not declared him fully healed and therefore Garro was deemed unfit for battlefield operations. His command remained at a limited duty standing. If he tried to lead the 7th Company, would risk failing them and that was a chance the Death Guard couldn’t take. He would not be going down to Isstvan III. These orders came directly from First-Captain Calas Typhon. Garro was to be stationed aboard the frigate Eisenstein during the assault on Istvaan III, while Commander Inatius Grulgor of the 2nd Company kept a close eye on the Terran Battle-Captain. They were both to be assigned to duty stations with their command squads aboard the Imperial warship. This would be a supervisory posting. The rest of their Great Companies would remain in reserve. During the assault on Isstvan III and the Choral City, they would provide standby tactical support for the drop-pod deployment operation, and remain on alert to perform rapid-reaction interdict duties.

First-Captain Typhon had pulled Commander Grulgor aside and spoke to him of their Primarch’s desire to bring Garro to the Warmaster’s banner over Terra’s, but they both knew that Garro would never change. He was too much the Emperor’s dutiful warrior. Realising the First-Captain’s intent, Grulgor deduced that this was the turning point, as he saw an intention emerging: the unusual patter of mission assignments to specific units from the Legions, instead of complete companies. The Commander realised that the Warmaster sought to isolate the elements that did not share his convictions. When the turning point arrived, Typhon informed Grulgor that there were certain duties that Horus would want him to perform. The Commander agreed to take part in this conspiracy against the insufferable Terran Battle-Captain.

The Eisenstein
The Eisenstein was an unremarkable vessel, an older pattern of ship in the frigate tonnage grade, just over two kilometres in length from bow to stern. It bore some resemblance to the newer Sword-class craft, but only inasmuch as most Imperial ships shared a similar design philosophy. Garro knew that they would not be making much history on this day. Their Primarch had ordered that they maintain orbit at high anchor and watch for enemy ships that might attempt to escape Istvaan III under cover of the ground assault. Garro became suspicious of Commander Grulgor’s manner as well as their orders to change position and drop into lower orbit, deepening his uneasy feelings he had about the entire operation. Though the Battle-Captain suspected something was terribly wrong, by Terra, he didn’t know what it was. Had they been carrying drop-pods and Astartes for a second assault wave, then the reasoning behind the orders would have been clear, but the frigate was not configured for those sorts of operations. It was, in the most basic sense, only a gun carriage.

Garro’s housecarl Kaleb Arin, on behalf of his lord, traveled down to the launch bay to spy on Commander Grulgor and find out exactly what they had transported aboard the Eisenstein. When he saw them unload a crate and opened it to inspect its contents, he realised that things finally started to add up, such as the Commander’s presence at the unloading and the exaggerated delicacy with which the crewmen moved the capsules. The dark liquid contents contained within the glass pods represented something utterly lethal. With crystalising clarity he suddenly realised the threat that Grulgor’s cargo presented. He also observed the work gangs busy detaching the warhead cowlings from thruster-guided glide bombs, exchanging the explosive charges inside for the globes of liquid. The 7th Company Apothecary, Merric Voyen also had his suspicions, and had also stealthily made his way to the launch bay to investigate. He saved the housecarl from narrowly being captured by Grulgor’s men. Kalab shared with the Astartes what he had witnessed. Digesting what the housecarl told him, Voyen realised with growing horror, that the deadly cargo was Life-Eater capsules – an engineered viral strain of such complete lethality that it could only be deployed in the most extreme circumstances, usually against the most foul xenos. This bane-weapon was of the highest order, a world-killer. Only the largest capital ships were permitted to carry them in their armouries. Grulgor had brought it over from the Death Guard’s capital ship Endurance!

During the opening stage of the first assault wave, the Eisenstein picked up an unscheduled movement in their battle sector. They received a signal from another ship that a craft from the Lord Commander Eidolon’s ship, the Andronicus, from the Emperor Children’s Legion. At first they thought that it might be the insufferable Eidolon making an unscheduled mission flight down to the planet’s surface, eager to take part in the glory. But they soon realised that the lone craft was a Thunderhawk, behind it a cluster of Raven interceptors were in an attack delta formation. Confused by this turn of events, the Andronicus sent the Eisenstein a message ordering to destroy the ship on sight, as it was acting against the Warmaster’s commands and was to be considered a renegade. They suddenly received a message from the Thunderhawk. The occupant was none other than Garro’s honour brother, First-Captain Saul Tarvitz. Garro’s mind was awash with confusion: a rogue Thunderhawk, the signal from Eidolon, the incredible command to terminate the fleeing vessel and the ranking Astartes officer aboard it...First-Captain Saul Tarvitz. Was this some kind of test? Some bizarre sort of battle drill to assess the mettle of the Eisenstein’s command crew? Or could it be true that Saul Tarvitz had indeed turned renegade and was fit only for execution? If it was possible for Istvaan III’s Imperial governor Vardus Praal to go against the Emperor, then perhaps an Astartes might do the same. Tarvitz’s next message was a dire warning, telling Garro that the entire operation was treachery. All of it, for they had been betrayed! The fleet was going to bombard the planet’s surface with virus bombs.

Tarvitz swore on his life that he would not lie to his honour-brother. Every Astartes on Istvaan III was going to die. Coming to a quick decision Garro acted of his own volition and ordered the Eisenstein to destroy the Thunderhawk. But in actuality he had destroyed the lead Raven interceptor, whose explosion caught the other interceptors in its wake, due to their close formation. As Tarvitz Thunderhawk was close to Istvaan III’s atmosphere, he used the sensor disruption to slip away. Garro’s men had just witnessed their commanding officer disobey a direct order from their superior. This was dereliction of duty, grounds for severe chastisement at minimum. If the Warmaster learned of the Battle-Captain’s insubordination, it would taint them, and the entire Death Guard. Nevertheless, Garro order the ship’s crew to contact the Andronicus and inform them the rogue had been destroyed, and the explosion claimed their pursuit ships as well. No survivors. Though some of his men were uneasy by the Battle-Captain’s actions, Garro explained to them that as an honour-brother, Tarvitz only spoke the truth, and his words were no falsehood.

Garro soon saw the larger picture. He couldn’t bring himself to actually say the words aloud to his battle-brothers. The sheer horror of it, echoing inside his thoughts. Betrayal. He couldn’t make the word, couldn’t force it from his throat. That Horus himself, the magnificent Warmaster, had done this. The idea of it made him go weak. And with that realization there came another. If Horus had prepared this treachery, then he had not done it alone, it was too big, too monumental an endeavour even for the Warmaster to have managed by himself. Garro realised that Horus’s brothers would have taken part in this treachery as well: Angron, ever ready to take any path that led him to more bloodshed. Fulgrim, convinced of his own superiority and perfection over all, and the Death Lord himself, in secret conspiracy with the Warmaster.

To compound matters further, Garro’s housecarl arrived to the bridge and informed his lord that Grulgor and his men were loading the main guns with Life-Eater globes. With only Apothecary Voyen, Brother-Sergeant Sendek and his housecarl, Garro confronted Commander Grulgor and his entire command squad and handful of naval crew. When confronted by the Battle-Captain, Commander Grulgor made a seditious announcement, explaining that the Emperor had abandoned them, leaving the Legions behind so that he could flee back to Garro’s precious Terra. He had sold off the Legiones Astartes birthright to a council of weak-willed fools and politicians, taken civilians who had never known hardships or the kiss of war, making them lords and lawmakers in their stead. The Emperor held no authority over them. Only the Warmaster and the Death Lord could command them. What they were doing there, they did by the will of the Warmaster and Mortarion.

The three Loyalist Astartes and the human housecarl lept at their foes with righteous fury in their hearts. During the ensuing melee, the housecarl saw Commander Grulgor taking aim with his bolt pistol at Garro while he was preoccupied fighting off one of his men. Realising the immediate threat, Kaleb instinctively fired his stub gun, his shot released an instant before the Commander’s finger tightened on his trigger. The stub-bullet from the handgun struck the frame of Grulgor’s bolt pistol, striking off a girder near Garro’s head and arcing away in a ricochet. Reacting with preternatural speed the Commander turned and threw his battle knife at the housecarl, killing him. Grulgor’s errant bolter round presented a new threat, as it had ricocheted off the metal bulkhead and into one of the warhead spheres, releasing its virulent toxin within. Using the last of his ebbing strength, Kaleb launched himself forward and hit an emergency release switch. Garro flung himself under the closing blast shield door, landing hard and rolling out to where Voyen and Sendek were crouched in the next compartment. The hatch was proof against the bane. The housecarl had saved their lives, as well as the ship. Commander Grulgor and his men suffered the lethal effects of the released toxin of the life-eater virus and died in agony.

Garro explained to the rest of his men of the events of his confrontation with Grulgor and the virus bombs. He also told them of the Commander’s declaration against the Emperor and the horrifying results of the ensuing melee on the gunnery decks. He continued to explain to his horrified men the entire horrific truth. Grulgor and Eidolon were not two errant souls pursuing some personal agenda, but soldiers in a war of betrayal that was about to unfold. What they had done was not of their own volition, but under the orders of the Warmaster himself. Horus, with the support of Angron, Fulgrim, and though it sickened him to say it, their master Mortarion, had done this. As a lodge-brother, Voyen confirmed Garro’s words. There has been talk of the Warmaster at second- and third-hand in the lodges. Talk of how far away the Emperor was and of discontent over the commands of the Council of Terra. The tone of things had been strained ever since Horus was injured at Davin, after he returned from his healing. Horus had personally chosen all the units for the assault on the Choral City. He picked only the men he knew would not turn if he called them to his banner. The bombing would rid him of the only obstacle to open insurrection. Had Garro not been grievously injured on Istvaan Extremis, he had no doubt that he would be alongside their fellow Loyalists below on the planet’s surface, unaware that a sword was poised at their necks. The turn of events had played in their favour, and they had to seize the opportunity.

Flight of the Eisenstein
With the remaining Loyalists aboard the Eisenstein, Garro was determined to flee the Istvaan System and make for Terra. Now fully aware of the traitorous actions of the Warmaster and his accomplices, Garro had his men make an oath of moment upon his sword Libertas. Did they accept their role in this? Would they dedicate themselves to the safe carriage of the warning to Terra, no matter what forces were ranged against them? Did they pledge to do honour to the XIV Legion and the Emperor? His men all swore upon their Battle-Captain’s power sword that by this matter of his weapon, they so swore. It took a lot for an Astartes simply take action and not to question. Garro felt damned by the understanding that Horus would play that unswerving allegiance to his bitter ends. He had considered briefly the idea of opening up all of Eisenstein’s vox transmitters to maximum power and broadcasting the truth of the treachery across the entire 63rd Expeditionary Fleet. There were noble men out there, he was sure of it, warriors like Loken and Torgaddon in the Warmaster’s own Legion, and Mesa Varren of the World Eaters. If only he could contact them, save their lives; but to do so would have meant suicide for everyone on the frigate.

Every minute they kept their silence was a minute more for Garro to plan an escape with the warning. Kinsmen like Loken and the others would have to find their own path through this nightmare. The message was far more important than the lives of a handful of Astartes. Garro only hoped that once his mission had been fulfilled he might see them again, either back on Terra at the end of their own escape or here once more with a reprisal fleet at his back. For now, those men were on their own, as were Garro and his warriors. During the bombardment, the Eisenstein picked up another signal. It was another Thunderhawk on an intercept vector with their ship. It belonged to the Sons of Horus, assigned aboard the Vengeful Spirit. The pilot identified himself as Third Captain Iacton Qruze, formerly of the Sons of Horus. He claimed to be no longer part of his Legion as he could no longer be a party to what the Warmaster was doing. Garro let the Thunderhawk land upon the frigate. It bore three refugees; the Luna Wolf Astartes, Kyril Sindermann – a high-ranked iterator, lady Mersadie Oliton – and a former remembrancer Euphrati Keeler – and now first Living-Saint. Garro granted them sanctuary. When the Battle-Captain spoke with Eupharti afterwards, their conversation strengthened his convictions and belief in the Emperor's divinity.

Garro knew his lightly armed frigate was no match against the powerful capital ships of Horus’s blockading fleet. At the time, the Eisenstein was close to the rear edge of the fleet pattern. The ship’s Captain took the liberty of informing the fleet master’s office that they were suffering a malfunction in one of their tertiary fusion generators. It was standard naval procedure for a ship under those circumstances to drop back from the main formation, to prevent other vessels being damaged in case of a cascade failure and core implosion. But they knew that the ruse wouldn’t last. For they would be undone the moment they fired their main engines.

Realising something was amiss, First-Captain Typhon aboard the massive capital ship Terminus Est moved to intercept the small frigate when he had received no word from his usually boisterous minion Grulgor. He gave chase as the Eisenstein attempted to evade the guns of his ship. The frigate sustained severe damage from the massive guns batteries as it sped past. The crippled ship limped away from Istvaan III. It was severely damaged, and all of its astropaths aboard had perished in the firefight and their lone navigator was mortally wounded. The ship was incapable of interstellar communication and had little chance of successfully navigating its way across the Immaterium. Once inside the Warp, the damaged Eisenstein attracted the attentions of the Chaos God Nurgle, the Plague Lord, who had already claimed the Death Guard Legion as his future champions and had no desire to see Horus' rebellion against the Emperor suffer a setback. Because the Eisenstein's Gellar Field had been weakened by the damage the starship had sustained during its flight from the Istvaan System, the Dark God was able to snake his influence into the vessel. Nurgle's power resurrected Grulgor, his dead Astartes and the ship's crew who had sided with him, creating the first Plague Marines. The ensuing battle between the infected Warp creatures and the Loyalist Death Guard aboard the ship resulted in the death of the vessel's only Navigator. Grulgor, using a Plague Knife, managed to infect a member of Garro's command squad, the Space Marine Solun Decius, with the terrible daemonic disease known as Nurgle's Rot, and almost triumphed over Garro. However, Garro ordered the Eisenstein to make an emergency transition out of the Warp. Without access to the infernal power of Nurgle sustaining them within the Immaterium, Grulgor and his corrupted brethren were killed, their souls sucked back into the Warp, though Grulgor would later be resurrected once more as a powerful Daemon Prince of the Plague Lord.

Stranded hundreds of light years from any stretch of inhabited space, Garro ordered the Eisenstein's captain to overload the Frigate's Warp-Drive and then jettison it out into space. Garro hoped that the detonation of the Warp-Drive would produce such a powerful signature in the Immaterium that any passing Imperial starships might be willing to stop and investigate. The plan would also guarantee that if no rescuers appeared, the Eisenstein would never reach another destination and its crew and passengers would die in the black void of interstellar space. However, the ensuing explosion of the Warp-Drive echoed across the Warp and acted as a beacon for the Primarch Rogal Dorn and the fleet of his Imperial Fists Legion, who had been becalmed by warp storms unleashed by the gathering power of the Dark Gods as the Heresy unfolded on their way back to Terra on the order of the Emperor. Dorn rescued Garro and his men and took them to Luna aboard the great mobile fortress-monastery, the Phalanx. While initially reluctant to the point of outraged violence to believe Garro about his brother Horus and the other Primarchs' betrayal of the Emperor, once faced with overwhelming evidence from multiple sources, including the testimony of a member of Horus' own Luna Wolves Legion, he eventually relented and the Navigators of Dorn's massive fortress ship made their way to the Sol System where Dorn would inform his father the Emperor of this dreadful news.

Luna
After arriving in the Sol System with the news, Captain Garro, his fellow Death Guard Astartes, Euphrati Keeler, and Iacton Qruze were all placed in a fortress on Luna that belonged to the Sisters of Silence while the Emperor determined whether they were truthful or were further pawns of the Chaos Gods. Even upon reaching Luna, and with the news of the betrayal delivered, Garro's trials were still not over, as one of his Astartes, Solun Decius, had become infected with Nurgle's Rot aboard the Eisenstein. Wracked by constant pain, Solun finally gave in to the temptations of Nurgle to ease his suffering and allowed his corrupted body to be possessed and mutated by a Greater Daemon of Nurgle known as the Lord of the Flies. His body was twisted by the possessing entity into a hideous daemonic form. In this state Solun killed the two Astartes who had been conducting the death vigil over his prone form. The Lord of Flies went on a killing rampage throughout the keep. Garro was forced to battle him throughout the Sister of Silence's citadel and out onto the barren, airless surface of Luna itself. He eventually bested the daemon who had once been his trusted comrade and banished the hideous entity he had become back to the Warp.

Afterwards, Garro, Qruze and the Sister of Silence Amendera Kendel were approached by Malcador the Sigillite, the Regent of Terra, and told that the Emperor needed them to form a new Imperial organisation, beyond the boundaries of the existing Imperial bureaucracy, which would utilise "...men and women of inquisitive nature, hunters who might seek the witch, the traitor, the mutant, the xenos". Under the Sigillite's own seal, Garro was tasked with finding 7 other Astartes from among both the Loyalist and Traitor Legions who were utterly devoted to the Emperor and his Imperium in body and soul. These Space Marines would form the core of what would later become the Grey Knights Chapter of Astartes, the Chamber Militant of the Inquisition's Ordo Malleus. The Inquisition had been born in the fires of betrayal and heroism.

Legion of One
After arriving on Terra, Garro's Power Armour had all of its Death Guard regalia removed and replaced with the personal sigil of Malcador, a stylised letter "I" with three horizontal lines through its center, this icon that would later become famous as the Rosette of the Inquisition. During his mission for the Sigillite, Garro consistently referred to himself as a "Knight Errant" and the member of a "Legion of One." Garro’s first mission was to war-torn Calth, amidst the surface of the battle-scarred world located in the Veridian System. The XIII Legion Ultramarines were engaged against their treacherous former brethren from the XVII Legion Word Bearers. Garro slipped past the Word Bearers’ flotilla and down to the surface of the war ravaged planet. He was looking for the 21st Company, under the command of Erikon Gaius. The 21st Company had been last sighted on the western outskirts of Numinus. They had been at the forefront of the first Word Bearers assault and it had been their sufferance to witness the deaths of too many battle-brothers. They were now a Company in name only. Their Captain – the Hero of the Hadier Uprising, Gaius the Strong, Gaius the Unflinching, had rallied them in the face of the brutal losses. With words and deeds he had led them into the fray, and they claimed back in blood the price from the traitors, but not enough. They were cut off from their kinsmen, holding one of the railroad approaches to Numinus City.

Garro sought battle-brother Tylos Rubio of the Ultramarines’ 21st Company, an extremely powerful Psyker who was once a Codicier of the XIII Legion before the Emperor’s formal decree at the Council of Nikaea which banned the Space Marine Legion’s use of psykers. Many resented the Decree, but honoured their oath to the Emperor and surrendered their Librarian panoply and wargear, returning to the lines as ordinary Battle-Brothers. In a succeeding Word Bearers’ assault Captain Gaius was killed when a large force of Traitor Marines and Chaos Cultists nearly overwhelmed the 21st Company’s battle lines. Garro arrived before the next assault and found Brother Rubio. He explained to the perplexed Ultramarine that he was there on the orders of Malcador the Sigillite and that he must come away with him. Rubio refused to leave his battle-brothers in the face of annihilation unless so ordered by the Emperor himself. Much to Rubio’s surprise, the honourable Garro respected his decision and agreed to stand and fight with him against the Word Bearers.

In the final assault, the Ultramarines were driven back in the face of overwhelming numbers, and sought cover within a cave. They were hard pressed by the elite Word Bearers’ Cataphractii armoured Terminators. Brother Rubio was sorely tested, forced to restrain from using his innate psychic abilities, bound by his sacred oaths to the Emperor. Though he knew by doing so he could have saved many of the lives of his fallen battle-brothers. Facing imminent death, Rubio felt that he had no other choice and unleashed a powerful psychic attack, driving the enemy back with the full force of his powers. The tunnel collapsed in the process burying the attacking Word Bearers Cataphractii under tons of rubble. The survivors of the 21st Company had been saved and the sole passage to Numinus had been denied to the enemy. The cost of using his powers had cost Rubio dearly – his Primarch and his Emperor. Garro told him to be grateful that he had saved his brothers. As he approached his fellow Ultramarines, they averted their eyes and as one and turned their backs, shunning him. Rubio had disobeyed a Decree Absolute, and for that, there was no forgiveness. Garro drew his sword Libertas and Rubio spun at the sound of it, fixing Garro with a furious glare. Garro held the sword out the point down towards the ground. He had Rubio place his hand upon the blade to take an oath of moment, to dedicate himself to the orders of the Regent of Terra and put aside all other claims upon his honour. Rubio swore upon the blade, for he had little choice.

The next Astartes that Garro recruited was Mesa Varren, a former battle-brother of the XII Legion Word Eaters. Like the former Death Guard, Varren too, had forsaken his own kinsmen after they swore fealty to the Warmaster. The lord of his Legion, the gladiator Primarch Angron, sent his personal guard to kill Varren for his refusal to join the World Eaters in their, sedition. Varren escaped with his life, and an embittered heart. Garro had offered him a new role as one of Malcador’s operatives, but in truth, the duty sat poorly with him. Quick to anger like all the World Eaters he longed to be out in the thick of the war, facing his former battle-brothers. He lacked the cool detachment of the Death Guard or the stoicism of the Ultramarine. The last warrior Garro was ordered to recruit was Captain Garviel Loken, formerly of the Sons of Horus. Though it appeared that he had perished during the final bombardment on Istvaan III, he had somehow managed to survive on the blighted surface. The Warmaster’s insurrection had long since moved onwards towards conquering other sectors. The world of Istvaan III was now a desolate and barren graveyard planet. Loken had been driven mad by the horrors he had experienced and believed that he been rejected by death. He experienced a form of amnesia and could no longer recall his name, taking upon himself the new identity of Cerberus, believing himself to be the sole remaining Loyalist in the galaxy until he was confronted by Garro. Loken perceived the group of Astartes as traitors come to kill him, forcing Garro to engage him in single combat, and soon he found he couldn’t overcome the maddened Astartes physically. Therefore, he appealed to his faith and reminded him of his duty to the Emperor. Garro reminded him who Loken truly was by revealing to him his name. In a moment of clarity, Loken recalled who he was and how he came to be on Istvaan III. He agreed to leave with Garro, becoming his final recruit for his mission from the Sigillite. They returned to Terra to learn Malcador's true purpose in gathering them together.

Wargear
Garro originally wore a suit of Mark IV ‘Imperius Maximus’ pattern Power Armour in his original Legion XIV Death Guard colours. Garro’s power armour bore an ornate cuirass etched in brass and gold. This was a ceremonial piece that Garro wore only in combat or upon formal occasions. This decorative over-sheath sported an eagle, wings spread and beak arched, sculpted from brass as if about to take flight from the chest plate. Similarly, the rear of the cuirass had a second eagle as a head-guard that emerged from the shoulders when worn over the backpack of his armour. After he fled Istvaan III and was charged by Malcador the Sigillite with a new purpose, he was later outfitted with Mark VI ‘Corvus’ pattern Power Armour, the most advanced wargear yet created (at that time) for the Legiones Astartes. Besides still bearing the ornate cuirass and the eagle behind his helm, there was absence of all other detail. His armour was a uniform stone grey from helm to boot, bereft of iconography. Sigils of echelon or honour of Legion and fealty were absent, all save one – a hidden rune upon his shoulder plates – a stylized ‘I’ etched into the metal of the ceramite, the mark of Malcador the Sigillite, the Regent of Terra and Adjutant to the Emperor.

In battle, Garro bore the ancient Power Sword Libertas. There were no visible imperfections visible in the crystalline matrix of the monosteel blade. It was said that this ancient sword pre-dated even its bearer. Some elements of the weapon having been fabricated on Old Earth before the Age of Strife.

Servants

 * Kaleb Arin – Kaleb was Battle-Captain Garro’s Equerry and Housecarl. Kaleb was a former Aspirant who failed the series of trials required for those who wished to become full battle-brothers of the Death Guard. Those that usually fail largely choose the Emperor’s Peace over a return in dishonour to their clans. But not all, as some lacked the strength of will even for this honour. Through some of the Legions made use of these throwbacks, it was not the Death Guard way. Thus, Battle-Captain Garro, as was his right, saved the failed aspirant and offered him a place within the Chapter as a serf. Kaleb loyally served his lord for many decades, and like Garro, held to the old traditions. Kaleb was also a secret adherent of the holy teachings of the Lectitio Divinatus, the sacred tome that extolled the virtues and divinity of the Holy Emperor. During the battle of Istvaan III, Kaleb was the one who discovered Commander Grulgor’s treacherous intentions, when he saw that he was unloading crates of the Life-Eater virus. The housecarl immediately rushed to the bridge and warned Garro of Grulgor’s duplicity. During the ensuing battle between Garro and Grulgor’s men, an errant shot from the traitorous Commander ricocheted off the ship’s bulkhead and struck one of the deadly containers, releasing the deadly bane. Kaleb sacrificed himself in order to ensure that Garro could fulfill his holy destiny in the name of the Emperor.