Legio Mortis - Notable Campaigns: Accatran Compliance (Unknown Date.M30) - After the events of the campaign to bring Accatran into Imperial Compliance, the Legio Venator could no longer be trusted to fight alongside the Legio Mortis without the threat of internecine conflict between the two rival Titan Legions.Ullanor Crusade (999.M30-000.M31) - The Ullanor Crusade was a vast Imperial assault on the Ork empire of the Overlord Urrlak Urruk during the Great Crusade of the 31st Millennium. The capital world of this Greenskin empire, and the site of the final assault, lay in the Ullanor System. The crusade included the deployment of 100,000 Space Marines, 8,000,000 Imperial Army troops, and thousands of Imperial starships and their support personnel. The Luna Wolves Legion spearheaded the assault with Titans from the Legio Mortis providing heavy support. Striking directly at the heart of the Ork empire, this force succeeded in killing the Overlord, thus casting the Greenskin horde into disarray and unleashing infighting within its ranks. In recognition of this great victory, Horus was elevated to the esteemed rank of supreme commander of the Imperial armed forces and granted the title of Imperial Warmaster.Lament of Shedim (Unknown Date.M31) - This was an Imperial Compliance action carried out against the Craftworld Aeldari upon the arid world of Anark Zeta between the forces of Craftworld Mór-ríoh'i and the forces of the Great Crusade, which included detachments from no fewer than four Titan Legions: the Legio Mortis, Legio Fureans, the Legio Atarus and the Legio Osedax. Overall command fell to Horus Lupercal, most-favoured son of the Emperor and Primarch of the Luna Wolves Legion. During the apocalyptic battle, the Legio Atarus was cruelly used, and without their foreknowledge, they were sent to probe the enemy lines of the Aeldari, and were subsequently destroyed. The grievous losses suffered by the Firebrands due to the Legio Mortis and the Legio Fureans' refusal to fight alongside them due to internal Mechanicum politics, was a grievous injury not soon forgotten.Cleansing of Murder (One-Forty-Twenty) (ca. 001.M31) - The world of Urisarach (nicknamed by the Space Marines who fought on it as Murder) was the twentieth world that was first encountered by the 140th Expeditionary Fleet, which was composed of three companies from the IX Space Marine Legion, the Blood Angels, commanded by Captain Khitas Frome. This deadly world acquired its nickname of "Murder" from the last transmission received from Captain Frome before the failed Imperial expedition was massacred by the local alien population -- a deadly arachnoid race dubbed the Megarachnids. Eventually it took a combined strike-force composed of elements from the Blood Angels, Emperor's Children, and Luna Wolves Space Marines as well as a Legio Mortis Titan battlegroup to initiate a full-scale assault that drove back the ultra-violent xenos.Assault on Davin's Moon (004.M31) - At the behest of Chaplain Erebus of the Word Bearers Legion, Warmaster Horus and his 63rd Expeditionary Fleet were requested to return to the Feral World of Davin. Erebus reported that the Imperial Governor of Davin -- Commander Eugen Temba -- had gone Renegade after he and his forces had gone to the moon in an attempt to bring the Davinite tribes there into compliance. Unfortunately for Commander Temba, the parley with the tribespeople turned violent, and he and his men were struck down by a sorcerous attack that had twisted their loyalty to the Imperium. The Renegade Commander and his forces took refuge on Davin's moon which they soon transformed into a Nurgle-corrupted swamp land. Supported by Titans from the Legio Mortis, the Warmaster led the assault force personally. It was here that the Imperial forces were first confronted by a horde of reanimated corpses of Plague Zombies which was all that remained of Temba's Imperial Army garrison. Ironically, the Death's Heads would later become corrupted themselves by the Chaos Lord of Decay, Nurgle. They did not know that they were fighting against the deity in the form of hundreds of disease-ridden Plague Bearers. It was during the Warmaster's confrontation with the daemon-possessed Temba that he would fall, gravely wounded by the mysterious Chaotic sword known as the Kinebrach Anathame.Razing of Prospero (004.M31) - Though their involvement now largely fails to figure in most official records pertaining to the destruction of the Thousand Sons Legion homeworld of Prospero, the Imperial Censure Host included in its ranks a discreet body of forces which can be described accurately as the Warmaster Horus' servants, which included two full maniples and one demi-maniple of the Legio Mortis. Commanded by the highly decorated officer Princeps Senioris Maldis Drane, the Legio Mortis was ordered to stand down by the order of Leman Russ, Primarch of the Space Wolves Legion, and supreme commander of the Censure Host. He believed that the Emperor's orders were for the Legiones Astartes to carry out the vengeance of the Emperor upon their brothers, and the impersonal goliaths of the Legio Titanicus had no right of involvement in that judgement. As the fates would have it, the Legio Mortis contingent would be almost wiped out against a foe they may have been there to confront all along in the shadow of the Censure: the forces of the Zhao-Arkhad Mechanicum sub-fane, the Titans of Legio Xestobiax, far beyond the precincts of the city of Tizca. The evidence of the Legio Mortis being present as part of the Censure Host sent to Prospero has largely been lost to history. This is not only because their involvement was tangential to the Battle of Tizca, but also because the vaunted Legio Mortis suffered a bitter defeat at the hands of a brother Titan Legion considered by Mars to be a degraded imitation of the Omnissiah's ideal. That the defeat of the Legio Mortis force was only prevented from becoming out-right obliteration by the intervention of the shadowed Ordo Sinister was enough to pull a final shroud of secrecy over the debacle.Isstvan III Atrocity (ca. 007.M31) - The campaign known in later times as the Isstvan III Atrocity began when the Imperial planetary governor of Isstvan III, Vardus Praal, had been corrupted by the Chaos God Slaanesh whose cultists had long been active on the world. In 005.M31, Praal declared his world to be independent from the Imperium. Unaware of the change in the Warmaster's loyalties, the Council of Terra charged Horus with the retaking of that world, primarily its capital, the Choral City. When the Imperium finally gathered their forces, the Sons of Horus, Death Guard, Emperor's Children and the World Eaters Legions arrived in the Isstvan System, mustering in orbit above the doomed planet. Under the guise of putting down the rebellion against Imperial Compliance, Horus hatched the plan by which he would destroy all the remaining Loyalist elements of the Legions under his command. He purposely gathered those Astartes who were not loyal to him and used them in the assault on the non-compliant world. With elements of the Legio Mortis Titan Legion in support, the invasion of Isstvan III then began in earnest. One of these terrible war machines was the infamous Imperator-class Titan, the Dies Irae (Day of Wrath), which had already gained a fearsome reputation amongst the Astartes of the 63rd Expeditionary Fleet. At the moment of victory and the capture of the Choral City the Loyalist Astartes involved in the assault were betrayed when a cascade of terrible virus bombs fell onto the world, launched by the Warmaster's orbiting fleet. Caught in the deadly bombardment, the princeps of the Dies Irae had the behemoth sealed against the deadly viral vapours, as his crew watched in horror as Isstvan III died around them, including many of the Loyalist Death Guard Astartes they had been supporting only moments before. Without the benefit of cooling systems and sufficient ventilation they were very nearly overcome by the intense heat when the secondary firestorm erupted. When the flames finally died down the Dies Irae went on to attack and help exterminate the remaining Loyalist forces within the ruins of Choral City.Schism of Mars (007.M31) - When open civil war erupted all over the Red Planet as the civil war within the Adeptus Mechanicus known as the Schism of Mars began, the Legio Mortis had already pledged their support to the Fabricator General and his co-conspirators of the Dark Mechanicum. Sallying forth from their fortress at Pavonis Mons, the Legio Mortis clashed with the Loyalist Titan Legion called the Legio Tempestus in open warfare near Magma City, but ultimately, these contingents of Death's Heads Titans were wiped out by the Loyalist Titan Legion.Ruin of Maedran (008.M31) - This battle of the Horus Heresy saw the Imperial colony world of Maedran on the edge of the Segmentum Solar become savagely contested between Loyalist and Traitor forces. Loyalist Titans of the Legio Gryphonicus, Legio Metalica, and Legio Destructor clashed with the Traitors of the Legio Mortis, Legio Argentum, and Legio Vulturum. One of the largest Titan battles of the early Heresy era, more than 200 god-engines clashed as Maedran was ultimately reduced to ruin. Ultimately heavy losses were incurred by both sides and neither combatant was able to claim true victory. In the aftermath, hatred between the Legio Gryphonicus and the Legio Mortis only intensified.Battle of Molech (008.M31) - The Legio Mortis was one of four Traitor Titan Legions that served at the Battle of Molech, providing fire support to the forces of the Warmaster Horus in his attempt to claim the planet and its secret Warp Gate for his own.Battle of Tallarn (010-011.M31) - The Legio Mortis is known to have fought in various engagements during the Horus Heresy, including the infamous Battle of Tallarn. During the Heresy in the early 31st Millennium, the Iron Warriors Traitor Legion, intending to destroy all potential resistance before landing, virus-bombed the world of Tallarn, rendering it an inhospitable desert. Only then did the Chaos Space Marines land. Tallarn's few survivors emerged from their underground bunkers to stop the Iron Warriors' invasion. Soon, reinforcements from both sides arrived, including the Legio Astorum Titan Legion. It soon became painfully clear to the Imperial forces the futility of fighting over a destroyed planet, but by then there was no turning back. Though it was not known at the time, the Iron Warriors were motivated to attack the world beyond their mere appetite for destruction because Tallarn was the site of a hidden and potentially powerful Chaos artefact. The poisoned environment of the world made it impossible for infantry troops to operate outside of their protective shelters, and so the only available option was to make use of armoured vehicles and the support of the Titan war machines of the Legio Astorum. The Legio Mortis fought their hated Loyalist kin from the Warp Runners, while the largest tank battle in human history erupted on the surface of Tallarn, involving some 10 million armoured vehicles. By the end of this brutal conflict, the Iron Warriors were defeated, and the wreckage of over a million tanks littered the sands.Siege of Terra (014.M31) - The Legio Mortis took part in numerous engagements during the dark days of the Horus Heresy, but their most notable action occurred when they took part in the Siege of Terra and the assault on the Imperial Palace. Horus commanded the Death's Head Titan Legion to break the walls. The fell Titans began to demolish entire sections of the bastion. The defenders inflicted dreadful carnage upon them - three, four then five massive Titans were destroyed in as many minutes. The Chaos Titans would not relent and they kept hammering away at the walls. The walls of the Emperor's Palace finally broke under the onslaught of the Death's Head Titan Legion -- its huge Warlord Titans smashed their way through the last few metres of the bastion and unleashed a flood of Traitors into the inner courtyard of the Palace. But despite their efforts, ultimately Horus was laid low by the Emperor himself and the forces of Chaos were forced to flee into the Eye of Terror.Siege of Hydra Cordatus (999.M41) - During the 13th Black Crusade, an Iron Warriors Warsmith, known simply as "The Warsmith" (Barban Falk), laid siege to the world of Hydra Cordatus in an attempt to steal samples of Imperial Fists' gene-seed from the Adeptus Mechanicus fortress located on the planet. This Warsmith's warband of Iron Warriors was supported by a battlegroup of Chaos Titans from the Legio Mortis, including the infamous Imperator-class Titan Dies Irae. Three Loyalist Warlords, two Reavers and two Warhound-class Titans drawn from the Legio Ignatum were stationed on the planet to provide support for the Mechanicus garrison forces. The Imperial defenders fought back bravely and many of the Traitor Titans, including the Dies Irae, were destroyed with the support of the Legio Ignatum 's God-Machines. Unfortunately, the Warsmith eventually conquered the world and captured the Imperial Fists gene-seed, which would be used to create new generations of Iron Warriors Chaos Space Marines, a victory for which this Warsmith was raised by the Ruinous Powers to become a Daemon Prince.