So I searched for a myconid monster class, and it seems that nobody has even attempted such a thing. Indeed, the reaction to the idea of a myconid player character tends to be "Why would anybody ever play a character that can't speak?"
To which I say: An inability to speak is not such an all-destroying handicap. For one thing, there's nothing that says myconids can't understand as many languages as they have INT bonus for. For another, I've had characters who had absolutely nothing wrong with their ability to speak, and yet went entire sessions, sometimes entire campaigns, saying nary a thing. And if it's that terrible and you absolutely cannot wait for rapport spores (which admittedly come fairly late), there's always Drow Sign Language, usable by anything with hands.
Another complaint is that myconids only live to 24 years old. To which I say: not so! A myconid has a life span of about 24 years. Notice that a myconid sovereign is "usually at least twenty-four years old". There's no well-defined upper limit. Though I suppose, say, 50 would be pushing it. Even so, a campaign usually doesn't last 20+ years anyway, even in-game.
So how do we make a myconid monster class? First, we need to come up with level adjustments for each level of myconid. Luckily, in the update from 3.0 to 3.5e, WotC provided LAs. Each kind of myconid has a LA equal to its HD, so any myconid monster class will gain HD every other level.
The second concern we need to conceptually deal with before starting to lay out a monster class is this: like true dragons, the standard myconid advances by age, not by experience. I'm inclined to solve this by saying that the character's current age puts a lower and upper limit on its myconid levels. If its current age is lower than the age range for its myconid level, then it must take class levels instead, as if it were done with its monster class progression, until its age increases. If its current age is higher than the age range for its myconid level, then it must take myconid levels.
The existence of various stages of myconid growth is both convenient and restrictive for a monster class. It's restrictive in the sense that each two-level pair has specific pre-defined abilities it needs to grant. It's convenient in the sense that it means for less thinking when determining what order to grant abilities.
Now it's a simple matter of plugging the six monsters into the monster class progression guidelines...
-2 Str, +2 Dex, -2 Int, +2 Wis.
Land speed 20 feet.
Immunity to all mind-affecting effects (charms, compulsions, phantasms, patterns, and morale effects).
Immunity to poison, sleep effects, paralysis, polymorph, and stunning.
Not subject to critical hits.
Plants breathe and eat, but do not sleep.
Automatic languages: none. Bonus languages: common, terran, undercommon, drow sign language. Myconids have no mouths and so cannot speak any language that requires speech, but they can understand, read, and write any language they know. Some take the time to learn drow sign language, to communicate with outsiders without using rapport spores.
Class Skills: Diplomacy, Intimidate, Knowledge (nature), Listen, Move Silently, Profession (farmer), Profession (herbalist), Sense Motive, Spot, Survival.
|Level||HD||BAB||Fort||Ref||Will||Skill Points||Age Range||Special|
|1st||1d8||0||2||0||0||(2+INT)x4||4-8||Feat, slam 1d3, Tiny|
|2nd||1d8||0||2||0||0||-||4-8||+2 Dex, +2 Cha, distress spores|
|3rd||2d8||1||3||0||0||(2+INT)||8-12||+2 Con, +1 natural armor, slam 1d4, Small|
|4th||2d8||1||3||0||0||-||8-12||+2 Str, +2 Int, reproduction spores|
|5th||3d8||2||3||1||1||(2+INT)||12-16||Feat, +2 Str, -2 Dex, slam 1d6, Medium|
|6th||3d8||2||3||1||1||-||12-16||+2 Cha, +2 Wis, rapport spores|
|8th||4d8||3||4||1||1||-||16-20||+2 Con, pacification spores|
|9th||5d8||3||4||1||1||(2+INT)||20-24||+2 Str, +2 natural armor, slam 1d8, Large|
|10th||5d8||3||4||1||1||-||20-24||+2 Con, +2 Wis, hallucination spores|
|11th||6d8||4||5||2||2||(2+INT)||24+||Feat, +2 Str, Potion Making|
|12th||6d8||4||5||2||2||-||24+||+2 Int, +2 Cha, animation spores|
Proficiencies: Slam attack only. Not proficient with any armor.
Feats: All characters gain a feat at first level and every three hit dice thereafter. A myconid with no class levels will gain these feats at 1st, 5th, and 11th levels.
Age Range: Myconids are unlike other monster classes in that they advance through hit dice by age.
If a character’s age is below the lower age limit for a level in the myconid monster class, they may not take that level, and must take a player class level instead.
If a character’s age is over the upper age limit for their current myconid level, they may not take levels in any class other than the myconid class.
Slam Attack: At 1st level, a myconid has a slam attack which does 1d3 damage. The damage for this slam attack increases as indicated at levels 3, 5, and 9.
Size Change: At 1st level, a myconid is Tiny, with a space/reach of 2.5/2.5, a size bonus of +2 to attacks and AC, a size bonus of +8 to Hide checks, and a penalty of -8 to bull rush, grapple, overrun, and trip attempts.
At 3rd level, the myconid grows to Small. Its space/reach increases to 5/5, its size bonus to attacks and AC drops to +1, its size bonus to Hide checks drops to +4, and its penalty to bull rush, grapple, overrun, and trip attempts drops to -4.
At 5th level, the myconid grows to Medium. Its size bonuses to attacks and AC, Hide checks, and penalty to bull rush, grapple, overrun, and trip attempts are all reduced to 0.
At 9th level, the myconid grows to Large. It gains a size bonus of +4 to bull rush, grapple, overrun, and trip attempts, a penalty of -1 to attack and AC, and a penalty of -4 to Hide checks.
Spores: As a standard action, a myconid of 2nd level or higher can release a cloud of spores. Every even-numbered level, a myconid gains a new variety of spore but does not lose access to the previous varieties. Each type of spore can be used a number of times per day equal to the myconid’s total Hit Dice (including class levels). A level 6 myconid, for example, has the first three spores (distress, reproduction, and rapport), and it can use each variety three times per day. The DC for saves to resist the effect of spores is equal to 10 + the myconid’s wisdom modifier.
Spores can be released either in a 120-foot spread or as a 40-foot ranged touch attack against a single target, as noted in the individual descriptions.
Distress: These spores alert all other myconids within the area that danger is near. They are released in a 120-foot spread.
Reproduction: These spores eventually germinate into new infant myconids. They are released as a 120-foot spread and have no detrimental effects on nonmyconids. A dying myconid of 4th level or higher will automatically release reproduction spores.
Rapport: Myconids do not speak, but these spores enable them to establish telepathic communication with each other and with outsiders. A successful Fortitude saving throw negates the effect, but it is harmless. Rapport last for 30 to 60 minutes with outsiders, but for 8 hours with other myconids. Rapport spores can be released as either a 120-foot spread or a 40-foot ranged touch attack. Regardless of the release area, communication range is 120 feet once rapport is established.
Pacification: These spores are released as a 40-foot ranged touch attack. The target must make a Fortitude saving throw or become passive for 1 minute. Being passive is similar to being dazed, except that the target can take partial actions that don’t involve attacking. This is a mind-affecting compulsion effect.
Hallucination: These spores are released as a 40-foot ray. The target must make a Fortitude saving throw or suffer powerful hallucinations that duplicate the effects of a confusion spell for 1 hour.
Animation: When released over a dead body, animation spores begin a process that covers the corpse with purple fungus. After 1d4 days, the corpse reanimates as a servant under the control of the myconid. A servant has all the characteristics of a zombie of the same size, except that it retains its previous creature type and it cannot be turned or otherwise affected as an undead. Over the course of 1d6 weeks a myconid-animated corpse slowly decays. At the end of that period it simply disintegrates into dust.
Potion Making: A myconid of 11th level or higher may choose the Brew Potion feat, even if it is not a caster (this is not a bonus feat). It can duplicate the following effects as a cleric or druid once per day (but only for the purpose of brewing potions): bull’s strength, cure light wounds, cure moderate wounds, cure serious wounds, delay poison, endurance, endure elements, greater magic fang, invisibility to animals, lesser restoration, magic fang, negative energy protection, neutralize poison, protection from elements, remove blindness/deafness, remove disease, remove paralysis, resist elements.
MMII does specify that "occasionally, an individual with more than two arms or legs pops up." That's interesting, not least because the randomly asymmetrical nature of myconids allows for odd numbers of arms and legs.
After it reaches adulthood and becomes mobile, "its appearance changes very little as it ages". That would seem to indicate that possession of extra arms and legs should be set at 1st level and never changed. However, I can easily imagine an errant sword chopping a myconid's limb near in two, and then the limb simply becomes two limbs. Moreover, myconids advance steadily in size through their lifetimes, so I'm inclined to write that line off as a generalization and allow extra limbs to sprout at any time in a myconid's life.
How do we represent it? Well, there are precedents. Most notably, the difference between a two-armed sahuagin and a four-armed sahuagin is a matter of +1 LA. I'm inclined to give myconids only one extra arm at a time, and I'm inclined to give it to them as a feat. Which means a myconid could spend two feats to get two extra arms, the same thing a sahuagin can get for an extra +1 LA. Is a level worth two feats? Let's ask the friendly neighborhood fighter: aside from your BaB and Fort saves, what kind of class powers do you get? A feat every two levels, you say? Let's call that an even trade, then. (Especially if we're using the level adjustment rules that make LA a more temporary thing than feat expenditure.)
Arms seems simple, but isn't: if you have an extra arm, you can wield an extra shield or one-handed weapon, a two-handed weapon and a shield, or simply have a hand free while carrying a one-handed weapon and a shield. But myconids get 2 slam attacks, one for each arm! Should we give them that, too? Well, consider the four-armed mutant sahuagin: it gets 2 extra claw attacks with its bonus arms.
I'm inclined to say "No, a character could just buy five extra arms and get five extra slam attacks." But that objection makes no sense, it could just buy five extra arms and five extra swords, and get five extra sword attacks, stronger than the slam attacks. Can a creature slam attack with a hand it's holding something with? Which is to say, could it buy five extra arms and five extra swords, then make five sword attacks and five slam attacks? Apparently, "a frost giant carrying a heavy weight in both arms doesn’t have a free hand to use for a slam attack. He’d have to drop the object (a free action) before making a slam attack." So the answer is no.
Plus warforged, for example, have two fists but only one slam attack. So I'm going to say no, the myconid doesn't get any additional slam attacks, though it can get additional weapon attacks if it uses additional weapons, though it may want to spend the buttload of feats it needs to do effective multiweapon fighting.
Legs seems a little more complicated, but isn't. I'm inclined to give a three-legged myconid quadruped status. On the one hand, the Monster Manual says "Any creature with four or more motive limbs can carry a load as a quadruped". On the other hand, Deities and Demigods says "any form with three or more legs" is affected by loads like quadrupeds are. The wording of the MM entry doesn't exclude the possibility that the D&D entry is true, so let's go with that. A third leg turns a myconid into a quadruped.
So let's write up some feats.
Extra Arm [Racial]
Prerequisite: Myconid race
Benefit: You have an extra arm.
Special: You may take this feat more than once. Each time you do, you sprout an extra arm.
Extra Leg [Racial]
Prerequisite: Myconid race
Benefit: You have an extra leg. You can carry loads as a quadruped.
Special: You may take this feat more than once. Each time you do, you sprout an extra leg. You never gain the benefits of being a quadruped more than once. However, if you should happen to lose one of your legs, you still count as a quadruped as long as you have at least three legs.