Fairy cup

The fairy cup, also known as abshroom, magu, or canker cap is a medium-size mushroom with a black exterior and a blood-red interior that is only found through Variations. It lacks any sort of structure typical of a mushroom, such as an underground mycellium network, a stem, or even any spores. Fairy cups can be dried and steeped into healing potions, particularly for fevers and rashes, and is sought after by foragers and herbalists.

Phenology and distribution

Unlike most mushrooms, fairy cups do not grow but are created. The typical method is to take a basket of common mushrooms, not necessarily edible, and leaving a basket of them beyond the stability of the local shrine or temple. With luck, they will undergo a Variation and transform into fairy cups. Usually the mushrooms will become any number of species, including poisonous ones, so it is up to the forager to ensure that harvested fairy cups are not contaminated with spores or bits of flesh from other mushrooms.
Fairy cups are very distinctive. The exterior is smooth and black with no signs of a stem or any other mushroom-like structure. The interior has a velvet-like texture and is deep red, with a faint smell of iron or rust. There are no other mushrooms, Variation or not, that are similar in color scheme and texture.
Their name derives from folk lore that faeries visit the baskets of mushrooms and spirit them away, thinking them to be akin to mortal babies, and leave detritus from their fae courts behind. Other mushrooms that are commonly discovered in Variations are named similarly, including the fairy's spoon, fairy sponge, fairysoap, and fairy lantern.
The regularity of fairy cups in supposedly random Variations raises many questions in philosopher's circles. Some theorize that, much like ocean waves, the scope of Variations ebb and flow. If mushrooms were left for longer or placed further away from civilization, they would surely turn into things that are less related to the original object. Others believe that mushrooms are, much like mortals, a key part of the Storyteller God's divine plan and are thus unlikely to variate much.