Event · M31
Burning of Prospero
The Burning of Prospero was Leman Russ’s destruction of Tizca and near-annihilation of the Thousand Sons Legion on Magnus the Red’s homeworld. The assault took place in the early Horus Heresy; the date is recorded variously, with accounts placing it around c.005–006.M31, roughly the same time as the massacre on Isstvan III. Before its ruin, Prospero was a cultured world whose capital, Tizca, housed the libraries and observatories of Magnus the Red and his Thousand Sons Legion. The action followed the Council of Nikaea, at which the Emperor forbade the Space Marine Legions from the use of psychic powers and sorcery, a ruling the Thousand Sons continued to defy. Magnus the Red, believing he had foreseen Horus’s turn toward rebellion, attempted to warn the Emperor by projecting himself psychically to Terra, an act of forbidden sorcery that breached the nascent Webway and left the Imperial Palace exposed to the warp. The Emperor ordered Leman Russ to lead a fleet to Prospero and bring Magnus back to Terra in chains for judgement; Horus, already secretly in thrall to Chaos, is recorded as intervening to turn the mission toward Magnus’s destruction rather than his capture. Russ’s Censure Host, drawn chiefly from the Space Wolves and accompanied by Constantin Valdor of the Adeptus Custodes, the Sisters of Silence, and the veteran Bjorn, fell upon Prospero and moved against Magnus, Ahzek Ahriman, and Amon. Tizca was razed by orbital bombardment and ground assault, its libraries and much of its population destroyed, and the Thousand Sons Legion was broken, suffering losses recorded as near-total. Magnus and his surviving sons withdrew into the warp, departing for the Eye of Terror, where the Legion afterwards allied openly with the forces of Chaos. Prospero remained lifeless for millennia until Magnus later ordered its reconstruction as a war-anvil in M42, and the Space Wolves and Thousand Sons have since fought a second time over its ruins, the world enduring as a point of connection, and enmity, between the two forces. Jaghatai Khan’s later crossings are recorded as linking Prospero to Terra and the Fenris system within the same record of Imperial censure that began at the Council of Nikaea and echoes into later events such as the defence of the Fang and the Rubric of Ahriman.
See where Burning of Prospero occurred on the galactic map during the Horus Heresy.