Fungi (the plural of fungus) are a kingdom of eukaryotic organisms, distinct from plants and animals. In real life, they cover a vast array of organisms, from humble yeast to the more iconic molds, mushrooms and toadstools. Mostly they are involved in the decomposition of organic matter. In fantastical universe, fungi can grow into forms very unlike anything on Earth, and are also known for causing Italian plumbers to grow taller.
In Dungeons & Dragons, the humble fungus has long been a supporting character throughout the editions. At its most basic, you have exotic background fungi, such as tree-sized mushrooms in the Underdark, with many species of edible, poisonous or even magical fungi often showing up in articles on the Underdark. Other fungi are even more spectacular, or at least memorable, because they can try to kill your adventurers. In 3rd edition and onward, these creatures tend to fall into the Plant creature type, even though they aren't in the same kingdom.
- Ascomoids are essentially puffballs. Just... grown to gigantic size. And semi-self-mobile. And hungry to chase down living creatures and squash them to a pulp to feed on their rotting flesh. So, actually, not all that much like puffballs really.
- Cushion Fungi, introduced in Dragon Magazine #172, are enormous carnivorous mushrooms that resemble plush cushions. They secrete soporific spores when they sense living creatures, causing the weak-willed to take a nap on the "cushion", which then smothers them before digesting their corpse. A fine example of Old School Roleplaying and the tradition of "Gotcha Monsters".
- Egarus, also known as Vacuum Fungus, is a voraciously energetic strain of fungus native to the Quasielemental Plane of Vacuum, which has the distinct and unpleasant habit of rapidly growing on - and disintegrating - any form of matter, inanimate or not.
- Gas Spores are infamous as one of the damn cheapest of D&D's long and sordid history of "Gotcha Monsters!" Far worse than the aforementioned Cushion Fungi. These toxic puffballs are full of lighter-than-air gas, which sends them floating around the place. And they just so happen to resemble the dreaded beholder. Exactly why has never really been explained in most editions, although 3.5's came pretty close to a satisfactory one by saying they were created as expendable decoys by beholder mages. If you're boring you could also just say "Natural Mimicry". In 5th edition, they're a magical fungus that grows on beholder corpses, and if you survive exposure to the toxic spores, you'll pick up fragmented memories of the beholder they originated from.
- Mu Spores, introduced in the Epic Level Handbook, are giant (at least 60 feet tall) walking mushrooms, with mouths that exhale deadly spores atop their heads, and bodies covered in sticky tentacles.
- Myconids, also known as Fungus Men, are a race of sapient, humanoid mushrooms native to the Underdark.
- Campestri are a devolved, dimwitted, surface-dwelling, music-loving relative of the Myconids.
- Phycomids are slithering carpet-like masses of predatory fungus that spew caustic alkaline goop at living creatures, seeking to kill them and feast on their flesh.
- Sargusian Fungi, commonly and inaccurately referred to as "Dirtwraiths", are a species of semi-intelligent predatory fungus native to the Abyss, but which can also be found in the Vesve Forest of Greyhawk, a result of a Bonehart wizard unwittingly bringing spores back with him after a trip to the Abyss and then accidentally sowing them around Delaquenn. This fungus attaches itself to plants and animates them, using them as weapons to kill living creatures so it can feed on their corpses. Demons love the stuff, they think it's a delicacy, but it's lethally poisonous to mortals.
- Shriekers are semi-ambulatory mushrooms that are harmless... in the way that a burglar alarm is harmless unless you trip it. If these things bump into something, they scream. Very, very loudly. And whilst they can't hurt you, anything that hears the screaming and comes to investigate probably isn't so non-hostile.
- Vegepygmies, also known as Mold Men, are fungus-based humanoids that grow out of the bodies of people consumed by the alien fungus called Russet Mold.
- Vermeil Fungi are native to the Savage Coast of Mystara, and supposedly are related to gas spores. Taking the form of large, crimson mushrooms, these fungi explode in a thick red cloud that resembles vermeil when disturbed - worse, this has the same effect on cinnabryl as detonating smokepowder, allowing their toxic spores to spread the debilitating effects of the Red Curse.
- Violet Fungi are semi-ambulatory mushrooms that actively hunt living creatures, lashing out with toxic, flesh-rotting tendrils to kill and consume prey.
- Zuggtmoy is the demon queen of fungus. She's quite prominent due to her involvement with the Temple of Elemental Evil, which is home to many fungus creatures.
The 5e module Out of the Abyss has an entire section detailing the types of fungus that grow in the Underdark, largely because it relies on the survival mechanic to create artificial difficulty til the party reaches a city from the drow prison camp. It introduces some nutritional ones:
- Barrelstalks are pretty much naturally-occurring, edible barrels of water. Super useful for the starving escapee.
- Bluecaps are inedible on their own, but their spores can be used as flour to make something called sporebread or bluebread.
- Fire Lichen is a hot fungus that grows near geothermal vents. It's basically fungal wasabi, and duergar use it to make spicy alcohol.
- Ripplebark is an edible bracket fungus, really only unique in that it looks like rotten meat and tastes better cooked.
- Trillimacs are five-foot-tall grey-green mushrooms that can be harvested for faux leather and kinda shitty bread.
- Waterorbs are little... orbs of water. They hold about a gallon of drinkable water and can themselves be eaten, though they don't really taste like anything but water.
- Zurkhwood is basically a fungal version of redwood trees, growing in the form of huge forests. Only its spores are edible, but the mushroom itself is noted as being the replacement for timber in the Underdark.
...and some fun ones:
- Nightlights are fungal fluorescent tube lights. They're around 8 feet tall, lighting a large area around them as long as they're not uprooted. They even tap on and off like a tap-light when they're touched.
- Nilhogg's nose is a mushroom that grants its consumer super-smell for a few hours. Jury's out as to whether it actually looks like a nose.
- Ormu is more of a moss, significantly less luminescent than nightlights but useful for making glowing pigments.
- Timmask is also called "the devil's mushroom," mostly because uprooting it makes it explode into a cloud of spores that inflicts the poisoned condition and the effects of the confusion spell.
- Tongue of madness is a big fat tongue-shaped mushroom that forces its consumer to say every single thing that comes to mind.
- Torchstalks would be useful for making torches, since they burn for 24 hours straight when they're lit, except for the fun little quirk that sometimes they explode as soon as you light them.
Way back in the days of Mystara, the Known World Gazetteer #10: the Orcs of Thar introduced a short guide to the various fungi native to the Broken Lands:
- Foodshrooms are mushrooms that grow just about anywhere, especially on decaying organic matter. Marked by a sickly-gray, buboe-riddled "foot", a green trunk and a mud-brown hat, these are one of the major edible fungi of Thar, both in their own right and when they grow big enough to attract fungus-eating worms.
- Badshrooms are a poisonous mushroom that grows alongside foodshrooms, which means the local goblinoids consider them a right nuisance. They're all but identical to foodshrooms, but the colors are wrong; sickly green feet, sickly gray trunks and black-dotted mud-brown hats provide a clear warning to anyone with the patience to stop and look at them first.
- Biggiz are the largest shroom species in the Broken Lands, taking the form of huge, flat-capped mushrooms that can grow "ten ogres tall" and be "as wide as a purple worm". The hollow stems are a popular construction material in Thar.
- Futpuff is a purple-spotted green puffball fungus that goblinoids of Thar have learned to use as a primitive warning signal. When trodden on, it loudly expels clouds of spores, which also stink to high heaven.
- Rokstolk is a flat-capped mushroom that grows on metallic items that have started to rust. Rock-hard to the touch, rokstolks form encrusting mats over whatever metallic item is feeding them.
- Fireshrooms look like dead, gnarled branches in red and purple shades. They grow in areas of high heat, such as near lava pools, and quickly burst into flames themselves when agitated. Tharrians like to use them as a cheap source of fire arrows.
- Rustlemoss is a blue-grey discus shaped mushroom that grows on the sides of Biggiz. Characterised by a rotten egg smell, it's actually a powerful curative that can heal wounds and alleviate certain diseases. Thar goblinoid shamans are always interested in gathering batches of rustlemoss.
- Darksnap is a predatory fungus that grows on solid surfaces, such as cavern walls or the stalk of a biggiz. Sharing the same rotten egg smell as the more useful rustlemoss, darksnap grows large enough to devour a troll in one mighty bite. Do not confuse the two!
- Oozeshrooms are gray, stalk-shaped fungus tendrils that secrete a black, slippery goop when agitated. Carefully dried out, the oozeshrooms can be used as sculptable wood, whilst the sap is readily employed as a strong glue.
- Gooberries are fungi that grow on cavern ceilings, taking the form of berry-like bundles of sticky fungus nodules on the end of long, hairy stalks. The carnivorous fungus grows big enough to consume a goblin, but is itself quite edible.
- Wogar's Cups are cup-shaped giant red mushrooms that grow in dry, miserable places. Their inverted bell-cap holds water, and the mushroom secretes nectar into the water to attract insect swarms. Whilst the nectar-laced water is sweet and drinkable, the swarming bugs aren't likely to react well to people poaching.
- Weeping Fungi are massive, hairy-capped mushrooms that look sort of like weeping willows, hence their name. Their size makes them a popular spot for predators to ambush prey, or lazy humanoids to seek a quiet spot to rest. The branches are also viable for bows and arrows as well.
40K Ork Fungi
Since Orks share an affinity with fungus, it is of no surprise that within the Ork eco-system one of the most vital aspects that keep Ork society going is the growth of specialized 'Orkoid Fungus'. If anything, every single Orkoid species from the lowliest Snotling to the greatest Squiggoth both come from the same fungal spore (which would technically make them different phenotypes, not different species). Only changing via chemical or hormonal stages when the Orkoid is gestating. Ork spores grow in the wilderness, giving birth to new forms of Orkoid life. Different forms of Orkoid Fungus play essential roles in Ork society. Ork Settlements are surrounded by great patches of the fungi. Cultivated by Snotlings and eaten by Eating Squigs, they are a primal source of food in Ork society.
Gretchin cooks usually turn some Fungus into something fancy. Examples include Fungus Beer, Fungus Wine, Fungus Chips as well as potentially making Mashed Fungus, Poached Fungus, Baked Fungus Pie, etc.
Here are some types of Orkoid fungus identified by the Imperium.
These round fungi contain huge amounts of poisonous spores, which are released after they are broken or crushed. Snotlings use them as primitive fungus bombs, dropping them under the feet of an enemy. After they step on it, they will have to suffer a nasty whiff of toxic spores which gives the Snotlings some actual use in the battlefield other than meatshields or ammunition.
All Orkoids are immune to these spores, they only make them cough and gag. Puffballs cleaned of spores and stuffed with marinated Squig meat is a popular Ork meal as the fungus enhances the already flavor rich Squig to a new level. Spores collected from a different varieties of Puffballs are used to make Fungus Gas Bombs and for various medical uses.
Speckled Bloodshade Fungus
In appearance the Speckled Bloodshade is a deep red or purple fungus speckled with yellow or green flecks. It can be eaten by Orks and has important medical uses due to to its effect on the Ork bloodstream. This fungus is rich in molds and spores found in Ork blood and skin, so it can be used to enrich the blood to speed up the Ork metabolism, usually in fungus juice injection cylinders. It is also used to slow the flow of blood which is a great benefit in treating wounded Orks.
Mushlings and Snotrooms
This is what happens when a Snotling dozes off too much in the Fungal gardens. Snotlings feed primarily on fungus, often eating as much as they can. This in turn can lead to strange side effects, one of which is becoming a fungoid. Snotlings start to become lazy and feckless and eventually vegetate at the side of the drop, tuning into a Snotroom or Mushling; a fungus preserving the vestige of a Snotling face. These are usually eaten only on festive occasions, as they become tough and large.
This fungus can grow very large and it becomes quite hard to eat a big one in one go, hence its name. Gob-Buster has a tough texture and strong, spicy tang. Big and old ones are so strong Orks sometimes have to spit them out. Some Orks consider finishing a Gob-Buster a demonstration of self-endurance. On the other hand, their spicy and tangy flavor is used by Gretchin cooks to further enhance the flavor of Squig meat or other mushrooms.
Other types of fungus also appear but are overall too minor to be properly described other than they're all edible.
- Pink-Spotted Trottlecap
- Warted Nightbloomer