Seeds of Evil
The Outer Black, a name referenced in the German text Piercing the Darkness, is the name given to a place outside of realm of mankind and somewhere in the void where all manner of terrible things dwell. Whether they are demons, ghosts, aliens or something else entirely, the Outer Black seems to be the realm of the Demiurge, a being of great power and influence that controls the entities within.
The goal of the creatures that dwell in the Outer Black, as well, presumably, the goal of the Demiurge, seems to be to pierce the thin membrane that separates the creatures from the outside and the world of mankind, entering to cause death, destruction and mayhem. Seemingly, the more people believe in and accept the entities from outside, the more power they gain and more of a foothold they can acquire.