Alkilith

An Alkilith is easily mistaken for some kind of foul fungal growth that appears on doorways, windows, and other portals. These dripping infestations conceal the demonic nature of the Alkilith, making what should be a dire warning appear strange but otherwise innocuous. Wherever Alkiliths take root, they weaken the fabric of reality, creating a portal through which even nastier Demons can invade.

The appearance of an Alkilith in the world heralds a great wrongness and an imminent catastrophe. An Alkilith searches for an aperture such as a window or a door around which it can take root, stretching its body around the opening and anchoring itself with a sticky secretion. If left undisturbed, the opening becomes attuned to the Abyss and eventually becomes a portal to that plane.