Event · M42

Battle of Bastior

The Battle of Bastior was a major campaign of the Fourth Tyrannic War fought in M42 across the Bastior Sub-sector, when Hive Fleet Leviathan’s tendril Grendyllus struck from below the galactic plane into Imperial rear areas. Lord Commander Solar Arcadian Leontus coordinated the defence from the White Templars homeworld of Sanctum in the Formidyre System, with the Phalanx and Battle Group Faustus of Indomitus Crusade Fleet Sextus among the forces anchored there. As Tyranid swarms overran much of the sub-sector and pressed the Formidyre System, billions of warrior organisms made planetfall on Sanctum despite the Phalanx and Imperial Navy. Holdfast, the White Templars fortress-monastery, came under siege, and Norn Emissaries struck at Imperial command centres. Captain-General Trajann Valoris arrived with two Battle Groups of Fleet Sextus and Adeptus Custodes, struck down a Norn Emissary that had emerged at Konstantin Plaza against Leontus, and led the counter-attack that turned the fight on Sanctum and then relieved the Pyremoat and Kastayl Systems. Tor Garadon launched Imperial Fists from the Phalanx in support. Sanctum held as an Anchor World, though Tyranid infestations remained and the Swarmlord was still at large on its surface.

See where Battle of Bastior occurred on the galactic map in the 41st Millennium.

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