Greycaps

A dangerous and parasitic fungus found in damp subterranean places, greycaps can adjust their fleshy outer surfaces to mimic the surrounding environment in colour and shade, allowing them to blend in.   Unwary passers-by might brush against the bulbous growths triggering a dangerous reaction.
When disturbed a greycap will eject a cloud of soporific spores capable of rendering most creatures who breathe them unconscious or at the very least disoriented.   At the same time questing tendrils will uncoil from the base of the fungal growth and seek through the surroundings for any flesh it can latch onto - ideally that of unconscious prey.   The tendrils are hollow with barbed "mouths" and will burrow into exposed flesh to drain the blood of any unfortunate victims of their spores.
The danger is compounded since the greycaps grow in colonies, and when one is triggered to respond the sudden movement of prey who evade the spores of the first may well cause a second to react, and a third...

Scientific Name

Fungus