At some point after it was given form in the Warp, this Daemon was imprisoned and trapped within the mortal world. There, it was discovered by the Adepta Sororitas Order of the Blessed Inquiry. However, rather than destroy the Daemon, the Order sought to study it in order to find weaknesses in the Forces of Chaos. For the next three hundred years, they kept the creature in secret and lost many of their members due to its lies. Eventually, the beast partially freed itself and destroyed the convent whereupon it took the enslaved seven hundred souls and fashioned them into a work of art called the Screaming Cage. A young Ephrael Stern sought to commit suicide to escape the Daemon's predations but unknown to Asteroth, the enslaved tortured minds of the Screaming Cage resurrected her and instilled her with great power as well as hid her from detection. In the years that followed, Asteroth sought to find more souls to devour in order to fully free himself and return to the Warp.
Many decades later, Stern returned to the planet Parnis though had forgotten her past. After uncovering the Screaming Cage, her history was revealed and it was at that point that Asteroth emerged. Bring forth warp corrupted bodies of the fallen Order of the Blessed Inquiry, they attacked the Order of Our Martyred Lady as well as Inquisitor Silas Hand. The battle proved to be a distraction as the trapped minds of the Screaming Cage transferred their collective knowledge of Chaos into Stern's mind. She used this knowledge to empower Silas Hand into a force that was capable of fighting Asteroth. However, the Daemon was not defeated and instead fled into the Warp to escape destruction.