In 597.M32, the Warmaster of Chaos, Abaddon the Despoiler, launched his second offensive against the Imperium of Man and initiated the 2nd Black Crusade. This time, Abaddon placed a terrible curse upon the worlds of the Belis Corona Sector, infusing them with the touch of the Warp. Meanwhile, his Black Fleet attacked the sector's Imperial shipyards, destroying dozens of Imperial Cruisers being constructed or repaired. Before the Imperium could muster its strength to fight back, the Despoiler retreated into the Eye of Terror, his works complete.
As part of the 2nd Black Crusade, Abaddon wove a terrible hex upon a number of worlds close to the Eye of Terror, seeding them with the taint of the Dark Gods. Leading a small band of his elite warriors from the Black Legion, Abaddon breached the Imperial Navy base at Belis Corona. While his fleet launched a diversionary attack against the orbital shipyards, Abaddon and his Bringers of Despair, the strongest and most vicious members of the Black Legion's Terminator elite, landed on one of the system's outermost moons. Slaughtering the garrison, Abaddon crafted a complex sorcerous ritual using their mangled remains and invoking a curse that would sink deep into the core of the moon. Only centuries later would the curse awaken at the Despoiler's behest and do its terrible work, unleashing a mutagenic plague upon the Imperial defenders stationed there. By the time Battlefleet Corona had mustered to repel the attacks on the core worlds of the Belis Corona Sector, Abaddon had already departed, his mission complete.
Shortly after the assault on the shipyards of Belis Corona, an attack occurred on the Inquisitorial vaults of the world of Nemesis Tessera. Hidden beneath layers of ice and snow, the Inquisition had constructed a watch station from which to study the Eye of Terror along with hexagramatically warded cells to hold daemonic prisoners. It remains unknown if this was the work of Abaddon, but in a swift and brutal assault, one of the cells deep beneath the station was opened and the daemon contained within was released. By the time Inquisitorial forces had secured the facility, the attackers were gone, leaving only a trail of smoking corpses and spent Bolt shells to mark their passage.
- Black Legion: A Codex Chaos Space Marines Supplement (Digital Edition), pp. 31-32