The shrieker is a form of fungus found in many fantasy role-playing games. These fungi have also made an appearance in the computer game Dungeon Master.
The shrieker is a mindless plant that does have some ability to move (very slowly, over time). They feed off of both moisture and dead organic matter, playing an important role in the nitrogen cycle. Your
average shrieker is a four foot tall mushroom with movable foot type pods at the bottom, and an orifice on top capable of emitting very loud audible sounds.
The shrieker has developed a very interesting form of defense. Any light or movement on the vicinity of a shrieker will cause it to put off a high pitched whine that will last for several minutes. Any creatures
living in the vicinity of the shrieker will surely know about (and avoid), this fungus. So when they hear it go off, it acts as a sort of natural burglar alarm. Any creatures in the vicinity will most likely come to
investigate the noise.
Shriekers are often found in close proximity to violet fungus (a deadly plant in its own right). Their only natural enemies are purple worms and shambling mounds , who both consider them to be an
excellent food source. They are also frequently eaten by boring beetles who actually cultivate them as both a food source and living alarm system. There are almost no natural populations of shriekers out in
the wild. Almost all of them are cultivated or tended by either intelligent or unintelligent creatures. Humanoid creatures in particular like to use them to guard unknown tunnels.
Shriekers reproduce asexually via spores. They grow best in dark and damp environments, and any rapid change in ambient light levels will set them to shrieking. They are a variety of mushroom, and
some of them can safely be eaten by humans, while other varieties cannot. There is almost no way to tell poisonous shriekers from non-poisonous ones, but that is of little matter, as neither variety tastes very
good. They can only move at very slow speeds, and do not have the ability to survive outside the area of their mycelium. But that mycelium will often be large enough to fill entire rooms and caverns, and will usually have produced several shriekers.
My monster nodes are usually based upon material in the various AD&D rulebooks. But they are my own work, as I often expand the information. In some cases I will blatantly disagree with the source
material. None of them are cut and paste. You are free to use my descriptions in any material of your own (even commercial material), as long as I am credited as the source.