Adeptus Custodes - Era of Relentless Aggression, M41-M42: Note: All dates from this point forward are provisional due to errors in the Imperial Calendar, meaning these events could actually have occurred at any time from the early 41st Millennium to the early 42nd Millennium.Battle of Lion's Gate (ca. 999.M41) - Barely has Roboute Guilliman returned to Terra when the empyric bow waves of the Great Rift sweep over the Sol System. Riding their boiling crests comes a horde of Khornate Daemons, who burst through the skin of reality to assail Terra itself in what is also known informally as the "Second Battle of Terra." Though this is the Adeptus Custodes' nightmare scenario, they enact their Catastrophe Protocols with unshakeable calm and self-assurance. Storming out to meet the invaders alongside Guilliman's Ultramarines and a sizeable complement of the Sisters of Silence, the Custodians successfully deflect the Blood God's attempt to behead the Imperium with a single strike. Victory is bought at a steep price in irreplaceable lives, but it is victory nonetheless. In the battle's aftermath, Valoris and Guilliman quickly reach an agreement: the role of the Adeptus Custodes must change, for they can no longer effectively defend the Golden Throne from behind the palace ramparts alone.Indomitus Crusade (ca. 999.M41) - Roboute Guilliman announces the Indomitus Crusade, a desperate and determined undertaking by a combined Imperial force to drive back the rampaging armies of Chaos. As part of this crusade, the Ultramarines Primarch intends to bear Primaris Space Marine reinforcements and the secrets behind their creation to the far-flung and hard-pressed Space Marine Chapters. On the eve of his decision, a large number of Emissaries Imperatus step forwards, compelled by the spirit of the Emperor to accompany the crusade. These will be the envoys who bring Guilliman's gift to the Adeptus Astartes; their presence will ensure that even those Chapters the Primarch does not visit in person understand the gravitas of what they are offered, and set aside whatever mistrust or conservatism they might have in order to embrace the Emperor's beneficence in their hour of need.Carnage on Gathalomor Prime (Unknown Date.M42) - The Gathalamor System comes under sustained attack from the Heretic Astartes of the Word Bearers Traitor Legion. As their Dark Apostles summon creatures from beyond the veil, the fight turns viciously against the Imperial defenders. The Mordian 84th Regiment and the Sisters of the Order of the Argent Shroud dig in to stage their last stand in the grim ruins of Gathalamor Prime's macro-cathedrum, their prayers for salvation ringing out to the screaming skies above. Sure enough, even as hordes of Traitors and abominations mobilise to attack, the Emperor answers the cries of his followers. Teleport flares erupt through the Heretic lines, gold and silver lightning leaping as a combined force of Custodians and Grey Knights storm into battle. Bolters roar and crackling blades tear through Heretic flesh, Trajann Valoris and Grand Master Aldrik Voldus leading an assault that sees the Traitor army shattered into battling warbands. Inspired by the sudden arrival of veritable demigods, the Mordians and Sisters of Battle advance, hymnals rising from their ranks over the roar of Flamers and the scream of massed Lasgun fire. Blood slicks the streets around the macro-cathedrum, corpses piling in gory heaps as the Word Bearers and their Daemonic allies fight back furiously. Yet after three solar days and nights of unremitting savagery, the Chaos host is broken in the Battle for the Statue Steps. With fresh Imperial reinforcements flooding in to the wider Gathalamor war zone, the Custodians set course for Terra, leaving the Grey Knights to deal as they see fit with the unfortunates that they rescued from the macro-cathedrum.Giants and Gods (Unknown Date.M42) - Fighting alongside the Knights of House Krast, a Shield Company of the Adeptus Custodes storms the battle lines of the Necron Tomb World of Trynnect. They smash through the android xenos and obliterate the cabal of Crypteks at its heart, thus preventing the awakening of the ancient C'tan star god Zul'channec within the northern bounds of the Segmentum Solar.The Echovault (Unknown Date.M42) - Led by the ambitious Chaos Lord Hadrexus, a sizeable contingent of Black Legionaries fall upon the world of Dakhorth. They sweep aside the planet's defending regiments and advance to secure the ancient xenos ruin known as the Echovault. Before they can lay claim to this mysterious structure, two of the warships known as the Moiraides appear in orbit. The Custodians of the Dread Host deploy in force, securing the mountain pass that leads to the Echovault with squads of Custodian Wardens who hold firm against wave after wave of attacks. Meanwhile, multiple Shield Companies strike at the flanks of the Traitor force, pulling their formation apart and dividing their strength. Finally, a decisive force of forty Allarus Terminators teleports into the very heart of the Black Legion lines, tearing their command structure apart and slaying Lord Hadrexus and his Chosen to the last. Though dozens of Custodians fall during the fighting, they smash the Black Legion invaders utterly and send their remnants fleeing back into the Warp. As for the Echovault, it is left undisturbed, and a permanent garrison of Custodian Wardens left to watch over it.The Dangers of Excellence (Unknown Date.M42) - Amidst the horrors of the ongoing war against Chaos, it is deemed heresy for Administratum clerks to suggest the Adeptus Custodes could ever lose a battle, regardless of the odds. Fearing for their safety and their souls, many Adepts record campaigns as Imperial victories even before the first shots are fired, should so much as a single Custodian be reported active in that war zone. Needless to say, more than one star system is lost to subsequent disaster despite the Custodians' endeavours.Vadrian's Quest (Unknown Date.M42) - For millennia, the Adeptus Mechanicus has striven to maintain the esoteric technologies within the Golden Throne. Despite their best efforts, systems continue to fail, and no one still living knows how to repair them. Perceiving such dangerous ignorance as a manifest threat to the Emperor's safety -- and thus falling beneath the purview of the Adeptus Custodes -- Shield-Captain Heraclast Vadrian consults with Trajann Valoris and receives permission to seek a solution. He gathers a band of his finest warriors aboard the Cruiser Scion of Argo, and sets off following a lead that points to the lost Forge World of Morvane.On the Plains of Pallus (Unknown Date.M42) - Following the disastrous collapse of Lord Commander Ustrin's Victorium Crusade, Heretic forces break through the Imperial lines on a system-wide scale. Their advance is spearheaded by the Renegade armoured companies of the Vostokh 7th Regiment, led by the traitorous Marshal Griegor, whose battle tanks repel every Imperial force sent to stop them. At last, upon the rocky plains of Pallus, Griegor meets his match. Screaming into battle upon their ornate steeds come Shield-Captain Aadilus and his company of Vertus Praetors, Melta Missiles streaking from their Salvo Launchers to annihilate the lead vehicles of the Vostokh spearhead. The Traitor tanks open fire with everything they have, seeking to swat the seemingly outmatched Jetbikes from the air. Yet the Praetors weave effortlessly between the shots, weathering those blasts that do hit home and suffering only scant casualties before they split into hunting packs and begin criss-cross strafing runs over and between the enemy armour. More Renegade vehicles explode by the moment, the Vostokh gunners panicking as they find themselves unable to track their hurtling tormentors. Like a shoal of razorfish, the Custodians pick apart their enemies, losing less than a third of their number as they annihilate the enemy's numerically superior army. Marshal Griegor's Shadowsword is the last vehicle slain, its immense main gun proving worse than useless against the agile and resilient Vertus Praetors who reduce it to molten wreckage in a matter of solar minutes.Silent Crossing (Unknown Date.M42) - Since the inexplicable escape of Cypher, the mysterious Fallen Angel, from a high-security cell in the Imperial Palace, the Custodians charged with apprehending him have tirelessly attempted to reacquire their captive. Unable to find him on Terra, and following a trail of fading clues, Shield-Captain Daryth and his men have pressed out into the stars to continue their mission. Now they enlist the aid of the Sisters of Silence, bringing a band of the elite Witch Hunters aboard their frigate, Sol's Arrow, before making the perilous crossing of the Great Rift. The presence of the Silent Sisters seems to calm the madness of the Empyrean, at least enough to aid the Custodians in making their dangerous journey into the Imperium Nihilus. Amidst the madness, their Augurs do not detect the heavily-shielded Space Marine Strike Cruiser that follows in their wake, its hull night-black and its insignia veiled.The Osseus Tower Falls (Unknown Date.M42) - The Haemonculi of the Twisted Spiral raise a vast bone fortress to float amidst the gaseous atmosphere of Othana V in the Vordrast System. As their raiding skiffs strike at the planet's gas-mining platforms -- which directly serve Adeptus Custodes star keep Prescience -- it is clear the threat cannot be ignored. Several Shield Companies launch strikes against the xenos, with the Allarus Custodians of the Gilded Fist leading the attack. Teleporting into the nightmarish Osseous Tower, they overcome every fiend and abomination that assails them, before destroying the tower's gravitic membranes and sending it tumbling down to be crushed in Neptune's high-pressure depths. The surviving Drukhari flee aboard sleek warships that swiftly vanish into the Webway, while the Custodians evacuate in good order. Disquiet spreads, however, when several Custodians are found to be missing without trace at battle's end.The Wyrmslayers (Unknown Date.M42) - A Genestealer Cult calling themselves the Wyrms of the Ur-tendril are discovered by Ordo Xenos agents, entrenched amongst the Nordafrik under-archives on Terra. Captain-General Valoris refuses a request by the Deathwatch to send Kill-teams against this threat, instead leading the purge in person at the head of a huge Adeptus Custodes Shield Host. The Cult put up a brutal fight, their sheer numbers and fanaticism allowing them to drag down one Custodian after another and tear them limb from limb. Yet for every one of the Custodians that falls, hundreds upon hundreds of malformed cultists and Aberrants are slaughtered. At last, Valoris himself beheads the monstrous Broodlord that ruled over the cult. He orders the creature's disturbing inner sanctum burned despite the protests from the Ordo Xenos investigators -- Valoris refuses to let anyone other than his comrades witness the foul mural that decorates the sanctum's back wall, of a nest of fanged tendrils emerging from the heart of Sol itself to devour Terra whole...Zagstromp's Doom (Unknown Date.M42) - The Orks of WAAAGH! Zagstomp overrun the Iron Warriors' Citadel of Miseries after a gruelling three-year siege. Grown massive and powerful on a diet of constant warfare, and equipped with the looted tanks and war engines of the butchered Iron Warriors, Zagstomp's hordes board their ramshackle warships. Before they can attempt to punch their way into the Warp, Custodians of the Solar Watch materialise within the engine decks and mek bays of the Greenskins' capital ships. Guns blazing, the Custodians hold off the Orks long enough to plant vortex implosion detonators on every ship. The survivors then teleport back to their own ships and jump away into the Warp. In attempting to give chase, the Orks trigger the Vortex bombs, and their vast fleet -- which Imperial doomscryers warned would appear on the fringes of the Sol System if left unchecked -- is consumed by the ferocious energy storm that follows.Duty unto Death (Unknown Date.M42) - Amidst the shadows of the Imperium Nihilus, a small Imperial fleet finds itself beset by a pair of wayward Tyranid Hive Ships. The Imperial flagship, the Terra Nostra, is transporting Primaris Space Marine gene-tech under the protection of Custodian Wardens. Seeing that the fleet will soon be overrun, the guardians' Shield-Captain orders an emergency teleport to the nearby Death World of Loqe II. Pursued by Tyranid swarms, the Wardens retreat into the fume-choked volcanic highlands and prepare to defend their precious cargo to the last. Wave after wave of Tyranids surge up the perilous lava-channels, but the Custodians -- cleaving to their oaths of indomitable defence -- repulse every attack. A solar month later, a relief force of Marines Malevolent arrives in orbit and drives the Hive Ships away with thunderous firepower. On the planet below they find a single living Custodian Warden, grievously wounded yet still standing guard over the untouched boon of advanced gene-technology amidst a fortress of heaped Tyranid corpses.Into Shadow (Unknown Date.M42) - Upon the direct orders of Trajann Valoris, a small, fast-moving force of Custodians makes haste for the ruined remains of fallen Cadia. Details of their mission are suppressed, even amongst their comrades, but they are accompanied by a number of warriors drawn from the ranks of the Shadowkeepers.