Born in Warhammer, but I'm an Alpha-Level Psyker

(This novel's plot is purely for entertainment and has no bearing on or connection to the original Warhammer storyline.)

This is my first time writing, so please be kind if it isn't very good. For the Emperor!

Synopsis: The protagonist, Sterner (sterne), is the eldest son of a mid-hive family on an ordinary planet in the Ultima Segmentum. His parents went to great lengths to get him into the Schola Progenium, and he graduated successfully. With decent grades and a manageable psychic talent, he was sent to the Commissariat. His very first assignment, however, was to purge his own home planet, which nearly drove him to a mental breakdown. Later, before reaching the age limit, he happened by chance to join an Astartes Chapter/warband. That's right, it was...