"At his left hand moans a Daemon, bound in the shape of an axe. Its songs of blood and hatred echo forth, and fill the sky with a moaning that stirs the dead. At his right hand stand lesser Daemons, huntsmen all, straining at the leashes of the Hounds. They feast upon the shades and spirits they have harried, throwing morsels of innocence to each other, so that all may sample the sweetest meat...Behold, a Daemon Lord comes, and we are doomed."
- — From the Codex Daemonicus
Kha Ak-Lash Kha-Aksha, called The Usurper, is an infamous Bloodthirster, a Greater Daemon of the Blood God Khorne. It is written that Kha-Aksha is one of the most powerful Warp entities ever spawned. Exactly what deeds earned this being its name remain the preserve of those truly steeped in the most forbidden of lore, but some whisper that, having attained such power as to set itself apart from the Blood God, Kha-Aksha attempted to turn against its master.
Angered to such a degree by this betrayal that entire Daemon Worlds burned, Khorne is said to have imprisoned the Bloodthirster within a mighty axe of Warp-forged metal which he cast out from the Warp and into the cold, hard dimension of reality. The ancient and feared weapon known as the Axe of Kha-Aksha is spoken of in numerous texts known to the hell-seers of the Screaming Vortex and, so it is said, the most soul-blasted savants of the Inquisition's Ordo Hereticus. How many ambitious and brutal warlords have wielded the Axe of Kha-Aksha since then cannot be said; many of the Screaming Vortex's most infamous and bloodthirsty murderers have sought the axe, and a number have mastered it, for a brief time at least. In truth, all ultimately fall to the rage of the Bloodthirster within, for mortals cannot harness such power without a price being exacted. That price is, inevitably, the soul of the bearer, a soul so blood-engorged that it makes the most satisfying of meals for the daemon entrapped within the axe.
This Daemon Weapon is fabled across the length and breadth of the Gloaming Worlds. The Axe of Kha-Aksha is located on the planet of Messia. But, as every true Champion of the Blood God knows, such treasures are rarely to be claimed without a challenge. The axe is not lying around waiting to be picked up, but is instead in the possession of one of the countless millions of bloated mutants that shamble across the surface on Messia's night side. How the mutant came into possession of the axe cannot be known, but when the tortured light of Messia's polluted sun falls upon that wretched creature, it shall be transformed into a cunning and devious adversary, and at that very moment realise the true nature of the weapon clutched unthinkingly in its distended, filth-encrusted claws. When that happens, the once-lowly mutant will have in its possession the means of laying claim to the entire world -- unless it is opposed by another servant of the Blood God.
- Black Crusade: The Tome of Blood (RPG), pp. 120, 137