Kiavahr - Coming of the Raven: When the nascent primarchs were scattered across the galaxy, the nineteenth primarch, Corvus Corax, manifested in a barren chamber, deep beneath Lycaeus' glaciers. If it hadn't been for the timely arrival of a team of Lycaean miners, the primarch would likely have never been discovered. On Kiavahr this event passed unnoticed, as the newborn primarch quickly killed the only Kiavahran present: the cruel overseer of the work detail. As the miners decided to hide the strange boy they had discovered deep within the mines, Kiavahr's ruling elite, blissfully ignorant of their final fate, continued to amass riches and wealth by exploiting the miners.As Corax reached his maturity, so the rule of the Tech-guilds drew to an end, though the overseers would not know of it until it was too late to avert their doom. Corax led a masterfully conceived campaign that bled the prison-moon's authorities dry, taking small cells of freedom fighters on a range of missions, some to steal weapons, others ammunition, still more to sabotage key systems so that they would fail at the moment of his choosing.Eventually, that moment came and Corax led the uprising that would cast off the shackles of centuries of oppression. In a necessarily bloody battle, Corax and his fellow freedom fighters took the prison-moon. The bloodshed was great, for not all of the slave-prisoners had been imprisoned for their radical ideals; many were convicted killers and worse; the primarch was forced by necessity to utilise their fighting abilities and overlook their previous crimes, on condition they never repeat them after their bondage was cast off.In yet another convergence of great events, it was in the immediate aftermath of the liberation of the prison-moon Lycaeus and the opening salvos of the atomic bombardment of Kiavahr that the Emperor arrived to reclaim his lost gene-son in 922.M30. Unlike events surrounding so many other such meetings, however, the Emperor came alone, and the next day left alone. While it is known that the Master of Mankind and the nineteenth primarch spoke for long solar hours, what passed between them remains a matter of conjecture.Whatever the truth, one thing is known to have passed between father and son that night. The Emperor would leave Corax to complete his missions and to defeat the Tech-guilds of Kiavahr. Only later would he be ready to assume command of his Space Marine Legion. It was as if in leaving Corax to liberate Kiavahr on his own, the Emperor was ensuring the primarch learned and assimilated the most vital lessons of war.The Emperor departed, leaving His son to complete his task using only those weapons he had at hand. Those weapons turned out to be stockpiles of atomic barrages and mining charges the masters of Kiavahr had secreted on Lycaeus, believing them safe from the enslaved multitudes they ruled over. In their hubris, the guilds never imagined that the slave-miners might one day cast off their shackles and claim those weapons as their own.Even as the Tech-guilds sought to launch a counterattack against the massively outnumbered freedom fighters, Corax knew the terrible order he must give. Using the steep gravity well that tethered Kiavahr and its moon, the primarch committed to a full-scale bombardment of the vast manufactory cities below. As the atomic fires blossomed on the face of Kiavahr, Corax demonstrated that by slaying thousands, millions would be saved.This, some would later claim, was the lesson the Emperor meant Corax to learn, and one that would temper his nature against the numerous challenges few but the primarchs of the Legiones Astartes could fully comprehend. Their greatest cities decimated, the Tech-guilds had no option but to capitulate. Kiavahr was liberated and Lycaeus soon renamed "Deliverance" by its grateful people. The primarch had confronted that most terrible lesson of war -- oft times, the innocent must suffer for the sake of all. It was a truth the Emperor knew well, and one that Humanity as a whole would experience on an unprecedented scale within a standard century.