The Ordo Malleus is the branch of the Inquisition charged with the deadliest duty of all: the hunting of daemons and the sealing of every rent through which the warp bleeds into reality. Its Inquisitors study the anatomy of nightmares, learning the true names, weaknesses, and summoning rites of the Neverborn so that these horrors may be unmade wherever they manifest. It is a labour that stains the soul, for to know the enemy so intimately is to court damnation with every page turned.
The Ordo was forged in the wake of a catastrophe so terrible its very name is expunged from Imperial record, a daemonic incursion that convinced the Inquisition it needed specialists devoted solely to the Ruinous Powers. Its agents rarely act alone against such foes. When a manifestation threatens to swallow a world, the Ordo unleashes its Chamber Militant, the silver-armoured Grey Knights, whose pure souls and blessed blades were bred expressly to slay what mortal armies cannot.
Secrecy shrouds the Ordo Malleus more heavily than any of its sister bodies, for the knowledge it guards could damn entire sectors if it spread. Witnesses to a daemonic incursion are as often silenced as saved, their memories a contagion the Ordo cannot risk. Its Inquisitors wield weapons of arcane provenance, from psycannons to warded blades, and many walk the razor's edge of radicalism, binding the warp's own energies to fight the warp.
Though it stands among the wider Inquisition, the Ordo Malleus keeps its counsel apart, trusting few beyond its own conclaves. Its purpose is examined further in the glossary account of the Ordo Malleus, a duty as thankless as it is essential, for the daemon never tires and the veil grows ever thinner.