Drop Site Massacre - The Hunters: Around the twentieth solar day after the Drop Site Massacre, the XIXth Legion's fight for survival entered a new and bitter phase. By this point, the Traitors were aware that a significant force of Loyalists survived yet and had made a number of attempts to bring them to battle. Corax, however, was not to be drawn into an open confrontation as his heavily reduced forces had no chance of winning. Instead, he executed a series of strikes designed to divert and disrupt the enemy's operations and challenge their domination of the wastes surrounding the Urgall Depression.The greater number of Traitors left behind to scour the world belonged to the World Eaters Legion, led by their savage Primarch Angron. Despite the Loyalists' actions, the World Eaters rarely split their forces, instead scouring the depression and the wastes beyond in a vast and ravaging mass, their war cries audible for many kilometres all about. The other, smaller Traitor Legion contingents deployed differently, however, leading the Raven Guard to the conclusion that those left behind on Isstvan V were some sort of punishment detail or else represented elements of the Traitor Legions their Primarch had decided to keep apart from the bulk of their forces.This hypothesis was further evidenced as a number of these remaining Traitor contingents were revealed to be fractious and ill-disciplined, the glory and nobility of the Emperor's Great Crusade apparently forgotten to them. The Sons of Horus were often encountered in small bands of hunters, most accompanied by cyber-mastiffs able to detect the proximity of even the stealthiest of Raven Guard warriors and to track them across many kilometres.The Word Bearers, by comparison, followed their own unknowable ritualistic dogma and often stayed clear even of their own supposed Traitor allies -- perhaps because these actions would have prompted too many questions they would prefer not to answer of their "brother-in-arms." The Iron Warriors contingent, smaller but well provided for in terms of heavy vehicles and war machinery, scoured the wastes in compact armoured columns, the largest three of which presented Corax with the opportunity he had been seeking.The Raven Lord's campaign against the Iron Warriors armoured columns was to last several solar weeks and heralded some of the most intense fighting prior to the very final battles on Isstvan V. After many weeks of gathering vital intelligence, Corax mustered his forces north of the Urgall Depression and sprung an ambush against the smallest of the three Iron Warriors armoured columns. After striking the surprised Traitors, they quickly withdrew, leaving behind the corpse of several hundred Traitors and guttering hulks of dozens of vehicles.Though this battle paled into insignificance compared to the losses the Traitors had inflicted upon the Loyalists at the Drop Site Massacre and afterwards, in terms of morale it could not have been more important. The Raven Guard had struck a meaningful blow against the Traitors, and even if every son of Corax eventually died on the blasted surface of Isstvan V, they would do so vindicated and with honour.As Corax and several of the Mor Deythan watched the rear as the main body withdrew, they witnessed a phalanx of walkers -- their form unfamiliar but clearly the product of some esoteric discipline practised by Horus' Traitor Mechanicum allies. This was the first recorded sighting of the war engines that would come to be known as the "Blind-Hunters," a class of mechanical automaton possessed of a dark intelligence and a fearsome array of weaponry, and intended to hunt down every last survivor left upon the surface of Isstvan V. Their very existence and presence on the planet at that juncture was further evidence of the staggering scope and scale of Horus' treachery.