The Emporer's Holy Inquisition

The purpose of the Inquisition is to identify and destroy the myriad of potential threats to the Imperium and humanity.

We are divided into three Ordos:

Ordo Malleus - The Threat Beyond
Hunters of Daemons, the Ordo Malleus fights the threats from the Warp, The Chamber Militant of the Ordo is the Grey Knights chapter of the Space Marines

Ordo Hereticus - The Threat Within
The Witch Hunters, the Ordo Hereticus fight the spread of treason, mutation, and heresy, The Ordo's Chamber Militant is The Adpetus Soroitas.

Ordo Xenos - The Threat Without
Hunters of the Alien, The Ordo Xenos fight the vile aliens that plauge the Imperium, The Ordo's Chamber Militant is the Deathwatch Chapter.