Event · M30

Tesstra Compliance

The Tesstra Compliance was a Great Crusade war in which Alpharius and the Alpha Legion brought the world of Tesstra, heart of the Tesstra Conservation, into Imperial obedience. The Conservation was an alliance of totalitarian human colonies governing some eleven billion people through eugenic control and caste; when its rulers fired on Imperial emissaries, Warmaster Horus diverted two expeditionary fleets, one under Roboute Guilliman and one under Alpharius, to enforce compliance. While the Ultramarines struck at once into the Conservation’s outer worlds, Alpharius held back, launching probes, reconnaissance and raids. Guilliman, angered by the lack of visible progress, berated him in council and demanded that Alpha Legion forces be placed under Ultramarines command; Alpharius ignored him. The Alpha Legion then bypassed Guilliman’s line and attacked Tesstra itself, yet again delayed a full-scale invasion for more than a week while Conservation forces, including genetically modified Ogryn troops, concentrated around the capital city of Prime and its population of some sixty million. When the assault finally fell it was sudden and overwhelming. Conservation command and the abhuman cadres were broken; fleeing civilians clogged the roads and were cut down from the air and by armour. The battle left the great majority of Prime’s defenders dead and made an example of the Conservation. Guilliman condemned the cost and the deliberate prolongation; Alpharius is recorded as answering that a swift capture would have been too easy. The campaign became a standing illustration of the rift between Alpha Legion doctrine and Guilliman’s methodical school of war.

See where Tesstra Compliance occurred on the galactic map during the Horus Heresy.

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