Following the cataclysmic events of the Horus Heresy and the Schism of Mars, much of the Legion's history has been lost, so very little information remains about the original Titan Legion bearing that name.
That the Legio Excruciata is still remembered at all is due to the valiant efforts of a Loyalist group of Mechanicum rebels known as the Omnissian Faithful.
Abandoned by other Imperial forces, this well-organised group of Mechanicum Loyalists under the guidance of Lexorcist Raman Synk conducted several daring raids and acts of sabotage aimed at reducing the Dark Mechanicum's stockpile of arms and manufacturing capabilities on Mars.
Following one of these raids, the Omnissian Faithful were able to capture and purge a single Warlord-class Titan of the Legio Excruciata, the Belladon Ventorum, and use it to wreck havoc amongst the forces of the Traitor Fabricator-General Kelbor-Hal.
While this Legion shares a similar name with the Traitor Titan Legion called the Legio Excruciatus, it is unclear if both Titan Legions are related as was the case for the Legio Tempestus and the Legio Tempestor or if this is a mere coincidence.
Most of the Legio Excruciata’s achievements during the Great Crusade have been lost in the fires of the Horus Heresy.
Thankfully, some sources have survived, the most important being the construction logs of the great Temple-Tarantyne, one of Mars' most productive Titan construction yards. These logs confirm the existence and the construction of the initial complement of Titans of the Legio Excruciata before coming under the control of the Dark Mechanicum during the Schism of Mars.
Its initial STC-template corrupted by the foul and proscribed knowledge previously sealed away in the Vaults of Moravec but unlocked by the Dark Mechanicum, the Temple-Tarantyne continued to produce hideously corrupted versions of Mars-Alpha Pattern Warlord-class Titans for the armies of the Traitor Warmaster Horus. This role made the Temple-Tarantyne forge complex an important target for the Loyalist Mechanicum forces.
While the destruction of the Titan yards themselves were beyond the Loyalist resistance's meager resources, a group of Loyalists led by Princeps Kallistra Lennox conducted a successful raid on one of the nearly finished Titans, the Warlord Ajax Abominata.
Conducting a subterranean insertion via Mole, Princeps Lennox's small group emerged at the Warlord’s feet before overwhelming the perimeter's guards and fighting their way to Ajax Abomonita’s command deck. They destroyed the corrupted Titan by planting Demolition Charges in the Titan's cockpit, destroying its Mind Impulse Unit interface and moderati stations.
Having achieved their objective, the small group retreated before the Temple's guard before other Chaos Titans could intervene. While on their way back to their secret base, the group was rerouted by the Loyalist resistance's command to help extract a group of fellow rebels who had been pinned down by enemy forces after having located a heavily damaged but salvageable Kastelan Robot.
As the group discovered once they returned to the safety of their base, the scavenged Battle-Automata was the last survivor of a failed mission to Mars conducted by one of Malcador the Sigilite's mysterious agents known as the Knights-Errant. In this case a former Techmarine of the Raven Guard who intended to unleash a diabolically powerful Silica Animus, the Tabula Myriad, against the Renegades of the Dark Mechanicum.
Having been imprisoned in the dormant frame of the Kastelan Robot for several solar months, the self-replicating Abominable Intelligence quickly took control of the base's power-grid to evolve into a purely code-based life-form. Like the Chaos scrap-code that had infected Martian society at the start of the Schism of Mars, the Tabula Myriad now propagated through the base's Noosphere and hardlines, eradicating the Chaos scrap-code wherever it was encountered.
The Tabula Myriad soon took control over the entire base, although thanks to Lexorcist Synk's precautions, the computer virus was unable to take possession of the base's occupants. Using the base's Cogitators for its purpose, the Tabula Myriad soon developed a 4,267-step battle-plan that would end in the defeat of the Dark Mechanicum and the capture of Mars.
Realising that the diabolical intelligence of the Tabula Myriad offered them the best chance at victory, the Omnissian Faithful willingly followed the abomination's plan, damning themselves as Hereteks in order to fight an even greater evil.
Unknown to the Omnissian Faithful, one of the Fabricator-General Kelbor-Hal's most trusted lieutenants, Magos Diemon Gordicon, formerly of the Ordo Reductor, had successfully planted an agent within the Loyalist resistance movement in order to discover the location of the resistance's secret base. Following the agent's hidden locator beacon to Phasmi Fossae, Gordicon led a powerful force of Thallax Cohorts, corrupted Krios battle-tanks and no less than three Warlord-class Titans in search of his illusive prey.
Using the base's perimeter sensors to infect the Titan identified as Belladon Ventorum and other units of Gordicon's forces, the Tabula Myriad caused the forces of the Dark Mechanicum to fight amongst themselves. Having purged Belladon Ventorum from all signs of daemonic possession, the Warlord was quickly claimed by Princeps Lennox and became the first god-engine of the reborn Legio Excruciata.
- Belladon Ventorum - A Warlord-class Titan constructed in Mars' Temple-Tarantyne after the Dark Mechanicum's victory in the Schism of Mars, Belladon Ventorum was a newly-commissioned Mars-Alpha Pattern Warlord originally intended as reinforcement for the Traitor Titan Legions when they would push on to Terra. Following the destruction of its sister-engine, Ajax Abominata, Belladon Ventorum was the first to react to the sabotage action but arrived too late to stop the Loyalist Mechanicum forces from escaping. Having been activated, Belladon Ventorum quickly joined the search for the Loyalist base, but was infected by the Tabula Myriad artificial general intelligence which battled and vanquished the daemon controlling the Traitor Titan before turning the Warlord’s guns on the remaining troops of the Dark Mechanicum. Belladon Ventorum was subsequently claimed by the Omnissian Faithful, now allied to the Tabula Myriad, and would conduct a one-engine war on the rest of Mars. Belladon Ventorum’s first target was the armour depot of the Legio Vendettica in the eastern part of the Mare Hadriacum.
- Princeps Kallistra Lennox - Although it is unclear from which Titan Legion she originally hailed, Princeps Kallistra Lennox was left stranded on Mars at the time of the Schism of Mars. Ripping out her bionic eye and burning out her plug-in-sockets as soon as she realised that the Chaos scrap-code propagated itself through the implants' link to the Mechanicum's Noosphere and other planetary Cogitator networks, Princeps Lennox attempted to join the Loyalist evacuation effort, but arrived too late to be transported to Terra. Intent on continuing the fight against the Traitors of the Dark Mechanicum, Lennox joined several reistance cells, always escaping their destruction by the agents of Kelbor-Hal before joining up with the Omnissian Faithful. Rising quickly through the ranks thanks to her military mind and experience on the battlefield, Princeps Lennox was put in charge of a strike team which proved itself a thorn in the Traitors' side. It was her team that successfully sabotaged the Warlord-class Titan Ajax Abominata at the very heart of the Titan yards of the Temple-Tarantyne. With the capture of Belladon Ventorum, Lennox's rag-tag band of fighters would become the crew of the newly acquired Titan and lead it into battle allied with the Tabula Myriad.
The Legio Excruciata’s colours are not listed in Imperial records.
The Legio Excruciata’s Legion Badge currently remains unknown in Imperial records.
- Heralds of the Siege (Anthology) edited by Nick Kyme and Laurie Golding, "Myriad" by Rob Sanders, pp. 11-40