Event · M30–M31

Cleansing of Laeran

The Cleansing of Laeran was the campaign of the Emperor’s Children, within the 28th Expedition Fleet and led by their primarch Fulgrim, that exterminated the Laer, a non-humanoid alien species, on their ocean homeworld Laeran, also designated Twenty-Eight Three. The Laer lived upon floating atolls of crystal coral. They possessed serpentine lower bodies and insectoid heads, and they shaped their bodies genetically and chemically to suit the roles of individuals; their warriors carried gauntlets that fired energy beams able to pierce Space Marine armour, and energised blades. The Laer were worshippers of Slaanesh, the Chaos god of excess. The campaign demanded great effort and sacrifice from the Imperial forces. At its conclusion Fulgrim took from a Laeran temple a xenos-manufactured sword later known as the Silver Blade of Laer, which he came to wield more often than Fireblade, his customary personal weapon. The blade was a daemon weapon, and its influence, together with the possible taint of Slaanesh upon the forces deployed against the Laer, is held to be the underlying cause of Fulgrim’s and his Legion’s turn to Chaos. The Apothecary Fabius, later known as Fabius Bile, studied Laer biology and afterwards used his findings to augment many of the Emperor’s Children. Dating of the campaign differs. One account places it during the Great Crusade, before the Emperor was entombed upon the Golden Throne. Another dates it to 893.M31, long after the Second Founding of 021.M31.

See where Cleansing of Laeran occurred on the galactic map during the Horus Heresy.

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