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-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. All enemies of the Allfather engendered hatred in the Sons of Fenris, but Magnus was placed in a different category of loathing. It had always been that way with the Thousand Sons. The sagas still recounted in the caverns of the Aett told of the sorcerers’ betrayal, their condescension, and – worst of all – their escape. The Legion had not been destroyed during the Burning of Prospero, only crippled. That shame had hung over the Space Wolves for over a thousand standard years