The Laer were non-humanoid aliens. They, along with their planet Laeran, were exterminated by the Emperor's Children (Pre-Heresy) during the 28th Expedition in a campaign that came to be called the Cleansing of Laeran.
All Laer maintain a snake-like lower body, with insectoid heads and mandibular features. But the Laer society genetically and chemically modified their bodies to better suit the task individuals were given, something that came to be a fascination with Apothecary Fabius Bile. Noted are aerial, land-based and aquatic warrior forms.[1a] They wielded gauntlets capable of firing green-hued energy beams, able to pierce Space Marine battle armour with ease, and also sported energized blades from which not even Terminator armour found refuge.
Fabius Bile would later discover that the Laer would genetically enhance members of their species from before birth to maximize the roles they would play in life. He would later utilize his discoveries from Laer biology to augment many of the Emperor's Children, and create the first Noise Marines.[1b]
The novel Fulgrim indicates this was before the Emperor's entombment in the Golden Throne, but White Dwarf 255 (UK) (UK edition) indicates that it took place in 893.M31, long after the Second Founding (021.M31). However, White Dwarf 255 is from 2001 and, as such, must be assumed to have been replaced by Fulgrim, which is from 2007.
- 1: Fulgrim (Novel) by Graham McNeill p. 22 and following.
- 2: White Dwarf 255 (UK)