Vardus Praal was an Imperial baron and the Planetary Governor of Istvaan III in the times of the Great Crusade. It is known that he eventually fell to the temptations of the Pleasure God Slaanesh, along with the majority of the planet's indigenous people.
The Warmaster Horus Lupercal, now newly corrupted by the insidious Dark Gods, would utilise the rebellion as a means to rid himself of the Loyalist elements that remained within both his own Sons of Horus, as well as three other Space Marine Legions under his command -- the Death Guard, Emperor's Children and the World Eaters.
Istvaan System Compliance
One of the more notable campaigns carried out by Primarch Corvus Corax and his Raven Guard Legion during the Great Crusade was the Imperial Compliance of the Istvaan System in 994.M30, located in the northern reaches of the Ultima Segmentum, far beyond the established heartlands of the Imperium.
Though cut off, scout vessels ranging ahead of Corax's 27th Expeditionary Fleet had found evidence that human life on Istvaan III had managed to maintain a largely cohesive industrialised society that had endured the millennia intact, making it a high priority for contact and absorption into the Imperium.
The military forces of the indigenous Istvaanians, including the renegade psykers known as Warsingers, were professional soldiers who did not break easily, even when confronted with the might of Space Marines. There was some resistance, but the last elements of the aggressive faction, including the Warsingers, were destroyed by the Raven Guard at the Redarth Valley on Istvaan III.
The Istvaanians kneeled as a defeated foe but were welcomed into the fold as men of the Imperium. Though they had waged war against one another, the Imperial Truth had prevailed and the Istvaanians had sworn to accept its teachings. By proving themselves men of wisdom and civilisation, they were deemed fitting partners for the many other worlds of the nascent Imperium.
The established planetary capital of Istvaan III, the Choral City, was chosen as the site of Imperial power and with the help of the Imperial Army Pioneer Corps and Mechanicum oversight, bunker and barrack networks were constructed to house its sizable new garrison, and the wrecked Precentor's Palace was raised again as an Imperial Castrum-fortress to house the seat of government.
Alongside this a star port was created to manage inter-orbital traffic, and the woefully inadequate defences reconstructed and fortified to required Imperial standards. Along with these developments came the usual procession of goods and technologies, as the agents of Imperial law, iterators and administrators flowed into Istvaan III, and an assigned Imperial Commander to govern the planetary system was installed.
The Istvaan System had required force to impose compliance so an outlander was chosen rather than a local to rule, and this task was given to Vardus Praal, formerly a Major of the XIth Lastran Rifles and later career politician of the Ultima Segmentum Court. Given Praal's record both as a soldier and civil administrator, he was deemed a "safe pair of hands" to carry the responsibility of shepherding these millions of lives through the transition to becoming productive and loyal members of the Imperium, and initial records show he set to his new role with gusto and considerable success was met in the initial years of his tenure, but this was not to last.
Conditions within the Empyrean in proximity to the Istvaan system grew steadily worse almost from the point of Compliance. Isolated as it always had been by distance from other inhabited spheres, it became increasingly difficult to reach by astro-telepathy and navigation as well. What reports that reached Terra, often relayed fifth and sixth hand from distant Expeditionary fleets and Rogue Traders on the periphery, and solar months old, spoke of a rising civil disorder, of iterators murdered and unexplained riots and outbreaks of mass hysteria in the cities.
The blame once more was centred on backlashes from the natives after attempts to forcibly dismantle local sects, the most dangerous of which was given the name 'Warsingers'. Matters worsened as Praal ordered the garrison to tear down temples and breach the sealed vaults of ancient religious sites in order to break the subtle but deep hold superstitious fears had over the Istvaanians and bring them into the light of Imperial Truth, but as to the success of this nothing could be ascertained as the warp storms which blocked Istvaan from the Imperium's core worlds worsened and all communications ceased.
Six years after the last official communiqué from Istvaan III, a Death Guard patrol ship on the outer edge of the Legion's fleet, near Neo-geddon on the very edge of explored space, picked up a faint echo of an Astropathic transmission from Istvaan III. Though garbled and incomplete, its central message was clear: Istvaan III was in open religious rebellion, the Imperial government had collapsed, and Vardus Praal, now turncoat and perhaps turned mutant or psyker -- the message was unclear -- was leading the revolt, and the streets of the Choral City running red with the blood of non-believers.
The message was estimated to be at least two years old, possibly six, but it could not be ignored. For Istvaan III and its tens of millions to have rebelled from compliance was a mar upon the Great Crusade that could not be tolerated, lest such sedition and malcontent spread, but that an anointed Imperial Commander who had received his office by the writ of the Emperor himself led the revolt was a crime that demanded the swiftest and most resolute punishment possible. It fell to Horus, the Warmaster, to bring Praal and all of Istvaan III to judgement, and he publicly vowed to make a fearful, bloody example to all the worlds of the Imperium of the price of sedition. But what few knew or suspected at the time was that the Istvaan III rebellion had provided Horus with the perfect opportunity to strike the first great blow of his own rebellion -- a blow that would fall upon his own.
For Horus the reconquest of Istvaan III would serve both to amass those forces loyal to him without suspicion, and also rid his own Legion and those of his closest allies of those within their ranks whose loyalties he suspected. The Istvaan system's distant location and the warp storms that still blocked it from Terra made a perfect screen for the dark deeds that were to come, and orders were given for four Legions -- the Death Guard, World Eaters, Emperor's Children and his own Sons of Horus, to rendezvous at Istvaan. Horus had a plan by which he would destroy all of the remaining Loyalist elements of the Legions under his command.
For the attack on the sprawling Choral City itself four primary target zones had been identified from orbit. The first was the heavily fortified Precentor's Palace and its environs which housed the seat of government, and presumably where the Traitor Vardus Praal might be located. This would be the focus of the Emperor's Children's attack.
It was in the plazas which adjoined the palace and formed the principal aerial intersection of the city's transport network that resistance was likely to manifest quickly, and this was given as the World Eaters' target to first seize and then spread beyond. The western fortification wall with its Imperial-built bastions and the bunker network they protected were to be the target of the Death Guard's assault, with the goal of either eradicating or boxing-in the garrison forces they contained.
The final, and perhaps most difficult, target was located in the east of the city; a vast and ancient complex of tomb-spires, shrines and temples known by the indigenous peoples as the Siren Hold. This complex had been in a state of near-disuse at the time of the first invasion and so left standing, but now long-range reconnaissance surveyor-scans showed the Siren Hold active again, with significant life signs and powerful anomalous energy patterns registering within.
Given the assumed religious focus of the rebellion and the psyker-witches also encountered on Istvaan Extremis, the Siren Hold too was afforded the status of a primary target and the Sons of Horus assigned to the attack with orders to destroy everything and everyone they found within. A score of secondary targets to be hit in the first wave were also identified, including the star port and several prominent infrastructural complexes and numerous smaller, splinter forces assigned to take or destroy.
After a lengthy bombardment of Istvaan III, Horus dispatched all of the known Loyalist Astartes down to the planet, under the pretence of bringing it back into the Imperium. During the attack on the Choral City by the forces of the Emperor's Children, Vardus Praal, armoured in twisted baroque splendour and wielding strange psycho-sonic weaponry, surrounded by his elite Warsinger bodyguards, encountered the Palatine Blade, Captain Lucius, of the III Legion's 13th Company, in personal combat. Despite Praal's Chaos-gifted abilities, he was no match for the Legionary's superlative swordsmanship, and the Traitor Imperial Governor fell to Lucius' blade.
Within hours the rebellion was in tatters with all of the invasion force's objectives secured and tens of thousands of the enemy dead in the wake of the assault. The victorious Space Marines were jubilant, their victory hard-won and well-deserved, but unbeknownst to them, disaster was about to strike. These Loyalist Astartes were betrayed when a cascade of terrible Life-eater Virus Bombs fell upon the doomed planet, launched by the Warmaster's orbiting fleet, unleashing the event known later as the Istvaan III Atrocity.
- Codex: Chaos Space Marines (6th Edition), pg. 9
- Codex: Chaos Space Marines (4th Edition), pg. 12
- The Horus Heresy - Book One: Betrayal by Alan Bligh, pp. 39-41, 46
- Galaxy In Flames (Novel) by Ben Counterxki