Allocution of Silence

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Inquisitorial Black Ship, personal vessel of Cornelius.

Description
Less perceptive augur operators could easily mistake its baseline energy signature for a scout sloop or similarly diminutive vessel, but the Allocution is actually moderately large by Destroyer standards at ~1.8km in length and nearly 400m wide at the fins. Of course, even the most skilled augur operators are unlikely to notice its signature at all when the craft is running silent. Sleek black and completely devoid of running lights, the Allocution is nigh impossible to visually detect, but its true stealth comes from the myriad arcane systems dedicated to managing emission and reflection of energy from across electromagnetic spectrum.

Strictly speaking the Allocution is a Symphalia Class Warp Runner - a long forgotten class unique to the Raven Guard circa M30-M34, fulfilling a role that has all but completely faded due to the overwhelming technological challenge of creating an escort weight-class vessel capable of riding the currents of the warp so speedily, while still mounting the necessary stealth and sensor systems. The few remaining comparable voidships active in the Imperium are jealously guarded by the Inquisitors, Astartes, and similarly powerful groups who have manged to maintain them down the long centuries.

The Allocution's interior is spartan but quite spacious given its history as an Astartes vessel, with wide corridors designed for Space Marines in full armour to move and fight in. Despite its prodigious age, time spent in Trazyn's collection and the diligence of its many thousand servitor crew members have kept the ship in immaculate condition; its light grey corridors show no signs of rusting, the utilitarian command throne (replacing the original, which was comically oversized for Cornelius) is perpetually dust-free, and the noise of the life support systems never rises above a gentle background hum. Stepping onto the vessel is something of a revelation for all but the most widely travelled of Imperial voidfarers - though clearly function-driven and well engineered in keeping with modern Astartes ships, the Allocution lacks the architectural bombast of its descendants and was relatively devoid of Chapter iconography even before Cornelius had most of the Raven Guard symbols removed (leaving some at the advice of Niko so as to avoid displeasing the machine spirits). The contrast with Imperial Navy voidships, let alone civilian vessels, is even starker - its engineering is vastly more efficient than a captain of today could hope for and, though completely lacking in luxuries (excluding the private chambers of Cornelius and some trusted staff), in many ways the Allocution is lightyears more suited to human habitation than the leaky, rattling rust-buckets that pass for voidcraft across much of the galaxy.

In its highly secure bowels, Cornelius has adapted the vessel to his needs. Expansive Astartes training chambers and hab cells have largely been converted for use by teams of elite Bureau analysts, with stacks of cogitator banks

History
Remeberancer record featured in The Horus Heresy: Book II - Massacre

Recalling events of 006.M31 leading up to the Dropsite Massacre of Isstvan V ''“The first Imperial vessel of the execution taskforce to break real-space at the edge of the Isstvan System was the Ad Temperesta, a purpose-build warp-runner and observation craft of the Symphalia class, belonging to the Raven Guard Legion fleet. Equipped with auspex shrouds and sensory systems unequalled by the vessels of any other Legion - save perhaps the XXth - there were few vessels better suited to the task before it anywhere in Imperial service. It exited the Empyrean a vast distance from the system’s core, and on a trajectory designed to mask its appearance, before using gravitational drives alone to impel it on its course. As a blacker shadow among blackness, life support and all extraneous power uncoupled and silent, its small crew of Legiones Astartes and augmented servitors conducted silent vigil amid the dark and ice-rimmed corridors and auspex chambers of the vessel as the Ad Tempersta journeyed on in a wide orbit of Isstvan’s star, seeing all, but remaining unseen. It watched and it listened. At first the Ad Temperesta found a planetary system deserted, save for the ghosts of the dead and the fading echoes of battle. Istvaan III was once a teeming sphere of human life that, years before, the Raven Guard themselves had brought into Imperial Compliance, but it was now a carcass world, shrouded in boiling black ash, scoured by the ravages of the life-eater virus and the fury of orbital bombardment. Radiation decay and still-cooling debris carried the evidence that a void battle had also taken place in the third planet’s vicinity, but of the culprits there was no signal the area around the system itself seemed devoid of enemy vessels. The tortured state of Isstvan III at least appeared to confirm the garbled intelligence the Loyalists had at their disposal, that on Isstvan III a great betrayal had been undertaken, and the blood of those who had remained loyal within the Sons of Horus, Emperor’s Children, World Eaters, and Death Guard Legions had been bitterly spilled. It seemed then that the Loyalists had been robbed of their vengeance - that the traitors had fled the scene of the crime - but the Raven Guard were patient hunters, and not so easily thrown from a scent. The Ad Temperesta pressed on, its course pursuing the ghosts of vox signals to a strengthening source on the system’s fifth planet. Here, at close range, the Raven Guard vessel discovered the truth - beneath Isstvan V’s dense upper atmosphere lay a blizzard of close range encrypted vox-traffic, half-masked power signatures and the heart-beat of tens of thousands of Legiones Astartes warriors - the shadow-signs of a vast army digging in. Here, on Isstvan V, the Traitors lay.”''

Later, the Ad Temperesta assisted in the evacuation of the survivors of Isstvan V, following the arrival of the Avenger in the system. Avenger took Corax to Terra to meet with the Emperor, while Ad Tempersta and another vessel returned to Deliverance, the Raven Guard homeworld.

Trazyn’s bottled ship showed the daring escape from Isstvan V by the Raven Guard - a particularly interesting event considering its ramifications on the Imperium and the involvement of so many competing factions

The vessel in Trazyn’s possession is not the original Ad Temperesta, which is believed to have been destroyed by sabotage committed by the Alpha Legion. The actual vessel is the Obscuratur, a sister ship of the Ad Temperesta that was undergoing fitting out in orbit around Deliverance during the battles of the Isstvan system. It went on to have a respectable but relatively unnotable career for several centuries before being lost to the Raven Guard. Its last recorded astropathic relay was notification that it was about to begin a warp jump, although whether the journey occurred is unknown.