I came up with these monsters starting with names from a random generator on Seventh Sanctum, here.
Also, because no one else will, and since I was exhausted and barely conscious when I wrote these last night, I'm going to rate them in the cold light of day with my rational mind and see how much justice I did to the name.
Doomvine - The name refers to 'doom' in its antiquated sense, for it is a very old thing first bred centuries ago in an Emperor's perfumed garden. Now it is encountered in the wilds, a densely woven vine like jasmine but far tougher, with coarse tripartite leaves and pale-pink trumpet buds. When the perennial plant is in bloom these many mouths speak, a chorus of tiny voices prophesying and answering queries with ironic truths. The plant sees far into many possible futures and deep into the past. The payment it demands for useful answers is blood be spattered on its buds for it to drink, and the fragrant buds slurp fresh blood up greedily. If payment is promised and not given, all the trumpets begin to peal and cry, calling dangerous predators to where the impertinent interrogator stands.
Rating: A; I really love the idea of weird plant species
created by magic. I mean for every owlbear you think there'd be ten
weird strains of flora, right? Also it's not necessarily a threat in
its own right, but creates an interesting dilemma (do you try to feed it
by "just" slashing your palm or arm, sacrifice someone to it, do you
dare trick it and run away? etc.)
Dusttorture Siren - Encountered on dunes or stretches of billowy sand. A living cloud of swirling silicates bound by ancient magic and terrible purpose. The cloud can assume any shape but can only speak with the roar of angry wind or a gritty, choked voice created by vibrating its particles. It solidifies atop dune hills in the day's glare, a lone feminine silhouette with the gentle wind like an alluring song spiraling outwards. The unfortunates who respond to this lure are trapped within the walls of a sudden dust storm, now solid, now shearing like razors. The siren can keep its victims alive for hours or days, buffeting them with sharp particles, sand whirling fast enough to strip flesh from bone. Eventually the siren leaves nothing of its victims but bleached bones stretched under the sun. It kills for no reason save to briefly alleviate its eternal boredom. Dusttorture Sirens can speak, but they have little to say beyond the desire to inflict pain. Each is bound to its dune, a roiling spiral of immortal frustration.
Rating: A; I had "Skin of Evil" in mind (an underrated early TNG episode IMO) when I came up with the personality of these things. They're spirits of pure evil, lonely and miserable. They're incredibly powerful (how do you fight a living dust cloud?) but sadistic enough to give a PC plenty of time to work out a way to escape if they get trapped in one.
Illusion Corpse - A simple type of undead, an immobile corpse that projects an insubstantial image of itself above the spot where its body lies. If the corpse is buried it can project this image over the hummus or stone sealing it, or the image can appear directly over a body. The image can appear as the creature did in life, now luminescent, or pale-and-spooky, but it is an illusory spell-like ability not a true ghost--the undead will is still in the corpse beneath. The illusion can speak. Illusion corpses are usually benign and may answer questions when encountered. Occasionally one might be an asshole and try to lure you into a trap. They may ask to be taken to a more proper resting place (or at least a more interesting one). If the body is moved, the illusion moves with it.
Rating: B; I like undead that aren't evil, just kind of sad and bored and want someone to talk to. Like the Doomvine it's not a threat in of itself, but a clever DM could figure out ways to make them menacing or helpful.
Murkchoke Brute - Imagine a walking clump of mud, tottering on elephantine legs sporting two Popeye arms. They range from the size of a dwarf to that of an ogre. Bodies sprouting reeds, twigs, dead leaves, splotches of algae or mold, they speak with burbling, sourceless voices. They are old, crotchety assholes. They would pummel you with their slimy fists as soon as talk to you. They will usually see intruders on to their bogs off with a stiff beating rather than kill, but they can drive their silt down an enemy's throat Clayface-style. They are a little more tolerant of Druids. Murkchoke Brutes are almost impossible to harm with ordinary weapons, but fire hardens their silt bodies with fatal consequences, as does freezing.
Rating: B; it's just an amphibious, less evil version of the Wizened Elder (MMIV3.5 I think) but I like the personality of a crotchety old Embodiment of the Wilds that just wants you to get off its lawn.
Ochre Root Hornet - It's a big mean hornet, 10" long, which burrows in soft soil with its tuberlike thorax sticking in the air like a big carrot bulb. Pull it up at your peril, its bite and sting are poisonous. They spend most of their lives mostly buried, eventually laying eggs out of their mouths. They are delicious, a common folk delicacy.
Rating: A. I love the idea of peasants having to battle one of these things to bring it back for Grannie's Secret Ochre Hornet Pie. More monsters should be like this---weird, annoying, but not truly dangerous, just something that adds a little more character to your Weird Fantasy World.
Shade Mummy - A wizened, emaciated corpse bound in faded wrappings on which is written the long form of a darkness spell in an ancient language. They generate an aura of darkness and creep silently, guardians of ancient tombs and warrens. Their touch spreads sickness and blindness. They can melt away in one shadow and reemerge from another in line-of-sight.
Rating: C+; It's just a generic stalker undead, but easier to kill than Shadows. I should probably remove Mummy Rot altogether and just have its curse simply be blindness.
Shadowy Talon Warrior - Related to the warrior caste of fey known as Thorns (see MMIII3.5, pp whatever), Talons are the height of dwarves. Their spindly bodies appear made of brown to straw-color briar vines, forming trunk, limbs, severe faces under spiky hair of throns. They wield two blades made of folded-up dry leaves and stalks. A select cadre of these are "shadowy," imbued with the power to virtually disappear in dusk or low light, teleporting between shadows to surround the foes of the fey. They can't go long though before their nature takes hold and they shout bold challenges and boasts before darting into battle. They serve one fey lord or another, their loyalties changing like the seasons in the eternal power struggles between the Seelie Courts.
Rating: B-; Of all the monsters, this one needs a good illustration the most to make it be more than just a generic warrior enemy. As it is, it's basically a variation on a monster that already exists (the Thorn), although I like the combination of dual-wielding ninja skills with snarky fairy attitude. I know I have a good picture in my head for these things, I just might have to rescue it with a good picture.
Tangler-Slime - It looks like an ordinary green slime, until it spews part of itself upon its target. The sacrificed mass hardens into a resin-like casing that fixes the victim's limbs, rooting its feet where it stands and allowing the core slime to feed at will.
Rating: B-; It's not bad, but it's just another type of slime, with a very straightforward gimmick. You fight one on Level 1 and never think about it again.
Tearspore - Parasite that infects unwitting hosts, then reproduces via gelatinous ochre-colored "tears" that seep painfully out the tearducts. At this late stage of infection the host body hardens, freezes, and then the parasite begins to feed from within. The tears trickle and splatter to the ground, releasing another generation of the airborne parasite.
Rating: D+; I like the name but all I could do with it was another generic "ahah you ingested an underground spore roll three Fort saves now you're dead" asshole trap-monster. Personally I feel like fungus is played out as a thing at this point? I would never use this in a campaign as the idea has been done better elsewhere. Maybe I'll try to reuse the name for something else another time.
Wolverine Hunter - All the worst parts of a weasel or mongoose with the size and limbs of a bear. A highly territorial apex predator. Actually wolverines win their skirmishes with these vicious mammals about half the time (wolverines are just too B.A.) Still, the ferocious shrieks of these predators instill terror in all that hear it.
Rating: B-; I shouldn't like this one as much as I do---it's just Animal + Other Animal, but how often do you see fantastical mammal predators? Basically never. Partly that's because there's lots of large mammal predators that can kill you already, it's not really a niche fantasy needs to fill. Also I have a soft spot for weasels, almost as much as for wolverines.
Lakefear Stealer - If you can, imagine a cross between a fish and a walking stick insect, about 9 ft long. With their skinny legs they cling to the surface of the water, but from beneath, drifting like a barely-submerged log. They stick to the bottom of fishing boats and occasionally clamber aboard to attack. They are attracted to shiny things: you can draw one off by flicking a coin into the water.
Rating: B+; a walking stick with the face of a river pike, basically--this is another monster that demands an illustration. I really like the fact that it's physically horrific but also really just a common nuisance. I imagine fishermen and other coast-dwellers get a laugh letting them scare outlanders before flicking a copperpiece in front of its face and sending it off. Like the wasp, this one is more "weird world flavor" than true threat.
Killing Thinker - Macrocephalic humanoid with gelatinous, purplish flesh. Their bodies are atrophied and weak. Their brains are huge and powerful, contained in swept-back, bulbous ridged skulls. They can kill with the unblinking stare of their huge, white eyes. they usually employ their telekinetic powers to hover, clad in simple flowing robes. They can read your thoughts, but they don't care. They experiment on humanoids for no apparent purpose, often kidnapping and dropping them into the middle of dangerous labyrinths. They can dominate a creature with their stare, or influence with whispers of their thoughts at long range. They pit creatures against each other and concoct strange scenarios for their own alien purposes.
Rating: C-. Another Star Trek/Beneath the Planet of the Apes style Big-Brain, I think every OSR bestiary has a version of these. The one gimmick these guys have is they will abduct you and drop you in a dungeon for no reason, but "their motives are beyond your ken" is a cop-out, and these guys lack personality.
Overall I started strong with the Doomvine and Dusttorture Siren but sputtered out towards the end. I'm not really one of those writers whose creativity benefits from being addled.