As the first warp storms broke over Holy Terra, its pollution-filled skies turned a roiling crimson. Khorne, heedless of the plans of his brothers and hungry to prove his superiority, sent forth eighty-eight cohorts of his Daemon legions to assault the Emperor’s Palace. The Blood God wanted the glory of tearing down the Golden Throne for himself, and so the skies of Terra congealed into bloodclouds that deployed the red host directly before the Lion’s Gate.

The gun batteries of the Imperial Palace are second to none, yet they alone could not halt this red tide. Led by Roboute Guilliman, the newly reappointed
Lord Commander of the Imperium, the Primaris Space Marines, Adeptus
Custodes and Sisters of Silence fought side by side. Although the rash Chaos
assault was turned back and broken long before it could reach the Eternity
Gate, the High Lords were shaken at the boldness of the foe. Without
the beam of the Astronomican, their arcane machinery and protective
devices were not enough to halt the fell powers from materialising even on
Holy Terra. Khorne, upon receiving the returning forms of his slain, grew so
apoplectic in his rage that his fortress trembled. So great was the heat from his outburst that the essences of the eight Bloodthirsters that led the failed attack were wholly obliterated.