Wolf Brothers - The First Battle of The Fang: The program for eradicating the genetic flaws from the legacy of Leman Russ was known as "The Tempering." For a generation, Hraldir worked on a cure for the Space Wolves' genetic flaws. No fleshmaker had ever discovered more than the Wolf Priest about the nature of the Canis Helix. It had become clear to him the Curse of the Wulfen could be eradicated while preserving the glory provided by the integration of animal DNA into the Space Wolves' gene-seed.Hraldir refined the gene-sequences of the Helix, altering them to deliver the supernatural strength of the Adeptus Astartes without unleashing the ravages of the Wolf Within. The products of these experiments created within the flesh labs of The Fang with the altered Canis Helix were as powerful as a true Space Wolf, as quick in the hunt and as skilled with a blade, but they did not degenerate into the Wulfen, nor did their personalities take on bestial characteristics.They possessed the qualities that made the Space Wolves superb warriors, and purged the genetic factors that prevented them from creating Successors. Yet they lived for only a short time. None survived for more than a matter of solar hours. Their deaths were difficult, and yet Hraldir had demonstrated to the Great Wolf Harek Eireik Eireksson that their goal was within their grasp. Given just a little more time, Hraldir would have set the Space Wolves on a new path.After the end of the Horus Heresy, Magnus the Red was determined to have his revenge for the devastation of his homeworld of Prospero at the hands of his former brother, the Primarch Leman Russ and his Legion. He devised a cunning plan to lure the Space Wolves into a trap in order to enact his final vengeance against them.The Thousand Sons Legion had not been destroyed during the Burning of Prospero, only crippled. Despite the grievous damage Russ had inflicted on them, the Thousand Sons still had the potential to launch raids into protected Imperial space, and the knowledge of that burned within Great Wolf Harek Ironhelm. It had angered him for solar decades, until nothing else seemed important.Magnus continuously taunted the Great Wolf on world after world. After many fruitless efforts by his Great Company to catch up with the Thousand Sons, Harek became obsessed, and took to searching worlds along the edge of the Eye of Terror itself. Eventually he found what he believed to be the Thousand Sons' secret base on the world of Gangava Prime and launched a full-scale attack against it, leaving behind only one Great Company to defend the Space Wolves' homeworld.The cunning Daemon Primarch made it appear to the Space Wolves that he was rebuilding his devastated Legion. But the situation on Gangava Prime was merely a feint, with the bulk of the Thousand Sons prepared to descend upon the Space Wolves' homeworld and level The Fang itself, ostensibly in retaliation for the Burning of Prospero. The real reason behind this retaliatory strike was not to simply strike at the Space Wolves out of revenge -- although most of Magnus' Legion were lead to believe this -- but to prevent the Space Wolves from successfully creating any Successor Chapters.To the Daemon Primarch, the future that Wolf Priest Hraldir had envisaged was worth striving to prevent, and so what remained of his Thousand Sons Legion would be sacrificed to put an end to the Space Wolves' dream. When Harek Ironhelm finally led the Space Wolves assault on the surface of Gangava Prime, he discovered, much to his shock, that the warbands of Chaos Space Marines he encountered there were actually remnants of the lost Wolf Brothers. They were Space Marines in profile, but horribly altered and mutated by the twisting corruption of the Ruinous Powers of Chaos.Though the Great Wolf wished to destroy the abominations personally, he had received word of the Thousand Sons' treacherous assault against the Space Wolves' homeworld, and so he destroyed the Renegades from orbit. Ironhelm left behind an Escort squadron to ensure that the devastation was complete. Magnus had known that Ironhelm would not refuse combat with corrupted Astartes of his own lineage. Had news not come of the battle on Fenris, Ironhelm and his Space Wolves would have hunted the last of the corrupted Wolf Brothers for many solar days, and The Fang would have fallen in their absence.