A daemon is a malevolent entity native to the Warp, the immaterial realm where emotion and belief take on independent form. Rather than being born in the physical universe, daemons are crystallisations of raw feeling: rage, desire, despair, decay, and every other passion cast off by living minds pools together until it coalesces into a thinking, hungering shape.
Most daemons are bound to one of the Chaos Gods, the vast Warp powers whose natures they embody and serve. Their appearance and behaviour mirror their patron, ranging from graceful and seductive to bloated and pestilent, and their power waxes or wanes with the emotional currents feeding their master. A daemon has no fixed body in the material world; to intrude upon reality it must possess a host, inhabit a crafted vessel, or exploit a weakening of the boundary between dimensions, often during a tide of bloodshed or worship.
When slain in the physical universe, a daemon is not truly destroyed but merely banished, its essence scattered back into the Warp to reform over time. This makes such creatures relentless foes, immune to permanent death by conventional means. Ranked from teeming lesser swarms to towering greater entities that rival legends, daemons stand among the most feared adversaries in the galaxy, their existence a constant reminder that thought itself can become a weapon.