Battle of Phall - Wrath of Iron: The Drop Site Massacre of Isstvan V was one of the major turning points that occurred early in the great galactic civil war that engulfed the Imperium of Man following the tragic events that played out on Isstvan III.After the news of the Isstvan III Atrocity was brought to the Emperor of Mankind by the Loyalists aboard the Death Guard frigate Eisenstein, He ordered the combined forces of seven Space Marine Legions to assault the positions of Horus and his Traitor Legions in the Isstvan System.During that assault on the world of Isstvan V, three Loyalist Astartes Legions -- the Iron Hands, the Salamanders and the Raven Guard -- were betrayed by the 4 other Legions of the Loyalist second wave -- the Alpha Legion, Night Lords, Iron Warriors, and a large contingent of Word Bearers -- who they had believed were loyal to the Emperor of Mankind, but in fact had already betrayed the Imperium and secretly turned to the service of the rebellious Warmaster Horus and Chaos.As the Loyalists retreated back towards what they believed were friendly lines, the hidden Traitors revealed their allegiance by opening fire upon the Loyalists, catching them between a Traitor hammer and anvil and nearly destroying all three Loyalist Legions.This victory demolished what the Loyalists had believed to be their numerical superiority and opened the path to the conquest of Terra for Horus and his allies amongst the forces of Chaos.The Primarch Perturabo and his warfleet had sat waiting patiently in the Isstvan System after the Drop Site Massacre, awaiting new orders from the Warmaster. Their patience paid off, as they soon received word from Horus that over 300 Loyalist warships were caught in a backwater system like fish in a whirlpool. A fleet of ships pinned in place and waiting for extermination, and here were all of those ships' dispositions and characteristics, listed and laid out for him.Though Perturabo knew that this was a fleet of one of the mighty Legiones Astartes, this wasn't just any ordinary fleet. This was a fleet composed of the Iron Warriors' most hated rivals, that of the sons of Rogal Dorn. The information had been gathered first-hand by scout elements in the system. But in the Lord of Iron's mind, he knew that the intel that he had received from the Warmaster was too perfect...too neat. How could the Warmaster have achieved such a thing? It was daunting in its implication.Perturabo realised that this was no random event, this had been planned before the Iron Warriors had come to kill the weakling Legions of Isstvan V. But then what else would he expect from the Warmaster? Perturabo thought of the massacre they had just committed, of the the Legions they had butchered. They were weak and destroying them had been nothing more than another task to be completed.But the Imperial Fists were rivals of old of the Iron Warriors, arrogant pretenders to honours and reputations they had bought with lies. The possibility of breaking Dorn's sons was a prospect so rich the primarch could almost taste it. This was obviously a part of the price of their allegiance to Horus. The chance to break one enemy bought by the deaths of others.The Iron Warriors' captains questioned the Lord of Iron of how they would be able to engage the Imperial Fists through the tumult of the raging Warp Storm. Perturabo responded that their passage would be possible, for the Warmaster had guaranteed it. That anyone could make such a guarantee staggered the primarch's subordinate commanders.Warsmith Forrix, one of Perturabo's vaunted Triarchs, cautioned the Lord of Iron that if the Imperial Fists suspected the possibility of an attack, they would be prepared. But Warmsith Berrosus, the 2nd Grand Company commander, interjected that if it was First Captain Sigismund who commanded the Imperial Fists fleet, then he would not sit patiently in his cage. Sigismund would make attempts to break through the storms, making them less prepared, and more vulnerable.Perturabo believed that, without a doubt, Sigismund commanded this fleet, for his brother primarch would not have trusted this fleet to another. Berossus offered to take his fleet, an equal number of starships, to launch an immediate attack to break the Loyalist fleet.The Lord of Iron struck down the Warsmith's request, informing his subordinate commanders that the Imperial Fists must not simply be broken, they must be ground to nothing.Dorn did not deign to come himself, therefore his favoured pup would bleed for him. All of the ships currently under Warsmith Berossus' command would go, but it would be the Lord of Iron who commanded the attack himself.