Tuesday, 23 August 2016

The Devil Strahd

No posts for a while because I've been on holiday in Devon. In Teignmouth you can still touch the cannon-balls embedded in the walls from when the French burned the place in 1690. Sadly the whole incident comes a bit too late for me to use it in The Coach of Bones...

Anyway. My employer has given me a bunch of Amazon vouchers in lieu of some actual money (presumably as part of some complicated tax dodge), so after reading Bryce's surprisingly positive review of the D&D5 adventure book Curse of Strahd I decided to buy a copy. It's tediously overwritten, terribly organised, and weirdly obsessed with treating every location like a dungeon even when there's no reason why it would be used like that in actual play: if I was a D&D5 NPC, my write-up would consist of a single short paragraph about me, followed by a three-page room-by-room description of my house. ('The understairs cupboard contains a vacuum cleaner, a broom, and a stepladder. They have no value as treasure.') But among all the pointless read-aloud text and mind-numbing descriptions of empty rooms there really is a lot of good material in this book, even if it can never quite decide how far into horror-fantasy it's actually prepared to go. Vampire spawn crawling along the ceilings. Animated scarecrows with rusty knife-blades for fingers and heaps of dead ravens stuffed inside their chests. The vestiges of the dead gods of hate entombed in slabs of enchanted amber, watched over by a senile lich so ancient that he has forgotten his own name. There's something there, y'know?

For me personally, though, the biggest weakness of the book is Strahd himself. I get that they're trying to evoke the classics, and that the whole thing is supposed to feel like a Hammer Horror movie in D&D, but it's all played so straight that I have trouble imagining many players being able to take the whole thing seriously. Frightened villagers. Looming castles. Wolves and bats and undead brides. An evil vampire lord wearing an evil vampire cape while sitting on an evil vampire throne. How much of that would your players sit through before they started doing crappy Bela Lugosi impressions? Twenty minutes? Ten? Five? I absolutely loved the mad druids worshipping Strahd as a dark spirit of the land, but come on... a giant wicker man with fangs and a cape? How is anyone supposed to find something like that scary instead of comic?

I think there's a simple alternative, though, and it's one that's hinted at within the book itself. The people of Strahd's domain don't really know what his deal is: they just know that 'the devil Strahd' has been up in his castle for pretty much forever, and believe that he had been placed in their land as punishment for some forgotten sin committed by their ancestors. So instead of making him a straightforward Dracula knock-off, why not draw on all that? Embrace the strangeness and the indeterminacy of it all. Give him his mystery back again.

How's this for an alternative set-up: instead of having Strahd openly riding around Barovia in a big vampire coach that looks it was stolen from Christopher Lee in 1968, make him a dark legend, something that people whisper about but never actually see. What lives in Castle Ravenloft? No-one knows. Something horrible. Something that creeps out by night to prey upon the people of the land. Vampires and zombies and wolves and witches do its bidding, but it is not any of these; it is something older and stranger, the embodiment of the land's collective damnation crammed into a human shape. How was the land damned? No-one knows. It coincided with the deaths of the Von Zarovich family - but correlation is not causation, is it? Various NPCs can still have theories about it - that the thing in Castle Ravenloft is their old lord, that he's become a demon, that he's become a vampire, that he's a black magician, that he could be redeemed if only he was united with his one true love, whatever - but there doesn't need to be any rush to confirm any of them. Even Strahd himself may not really understand what he now is, or how his powers work, or what (if anything) may ultimately be able to kill him. All that the adventure actually needs to function is some kind of brooding evil at Castle Ravenloft's heart; and given that Strahd is, frankly, kind of a loser, I'm inclined to think that the more his mystery is kept intact, the better.

I mean look at this guy. Honestly. This is your arch-villain?

I guess this ties back to a more general point about information management in horror games. Keeping your players completely in the dark is frustrating for everyone; but the more you reveal, the more you risk an 'oh, is that all?' reaction from the players. To these ends, it's probably worth distinguishing between functional information (what is going on and what can be done about it) and explanatory information (the reason these things are happening, the process by which this situation originally came to occur). The former needs to be something that the PCs can figure out; but the latter will often benefit from being left partly (although not completelyundefined, because the more thoroughly it's explained, the more its power will be diminished. This is especially true of things like zombies and vampires, which have experienced so much pop-culture over-exposure that they have lost almost all the symbolic power which they might once have possessed. ('He's just some stupid vampire? And to think I was worried he might be something scary!') There is a lot to like in Curse of Strahd, and I'm sure I'll be raiding it for my own use at some point. But for a horror story, it does rather over-explain things; and I think Strahd's nature, history, and motivations could all benefit from being made just a bit more shadowy. 

Wednesday, 10 August 2016

James Raggi Should Totally Hire Me...

...because I have a brilliant idea for a Lamentations of the Flame Princess adventure.

Lamentations has done a whole series of adventures set in seventeenth-century England: No Salvation for Witches, Death Love Doom, Forgive Us, England Upturn'd, and The Squid, the Cabal, and the Old Man. I've not read them all, but I think I'm right in saying that they are all set in the eastern part of England, which is over-populated and flat and boring. Everyone knows that D&D adventures should be set in hills and forests and mineshafts instead.


The setting is Devon in the autumn of 1685. The Duke of Monmouth's rebellion against King James II has just ended in bloody ruin at the Battle of Sedgemoor; in reprisal, Judge Jeffreys is riding from town to town with his judicial murder roadshow, the Bloody Assizes, and mass executions of actual and suspected rebels follow in his wake. The Second Tangier Regiment has been unleashed upon the civilian population. The hacked-off limbs of quartered traitors, painted with tar to preserve them, now stand impaled on pikes in the market squares of miserable Devonshire villages. Corpses dangle from the trees and hang in clusters from the gibbets, their chains clinking in the wind.

Into this chaotic situation stumble the PCs, lured by stories of ancient treasure hidden in the Devon hills. From the Doone Gate in Exmoor, where a clan of cannibal bandits guard the entrance to a hidden valley, to the wilds of Dartmoor, where the ghost of Lady Howard rides over the hillsides in her coach of bones, they will hunt among Druidic megaliths and the secret stashes of Sir Francis Drake while trying very hard not to get executed for being in the wrong place at totally the wrong time. But they're not the only ones looking for the treasure, and the infamous commander of the Tangier Regiment, Colonel Kirke, has send a team of his most merciless minions out to follow the trail on his behalf. Will the PCs find gold and power among the hills of Devonshire? Or will they, like the Duke of Monmouth, end their careers under Jack Ketch's axeblade up on Tower Hill?

The Coach of Bones: coming probably-never from Lamentations of the Flame Princess. Pirates, witches, ghosts, cannibals, magic, treasure, standing stones, large-scale violence, lame 'Captain Kirk' jokes... this one's got it all!

Monday, 8 August 2016

Denizens of the Wicked City 10: Clockwork beasts (AKA 'My new character will be DOCTOR CLOCKTOPUS!')

Clockwork frog by ClockworkFrog.

I have a clockwork robot character class. I have a talking animal character class. The next step seems pretty damn obvious.

Not all of the Brass Folk are built in humanoid shape, although most are. But sometimes someone installs a Brass Man brain in a different body: the body of a Bronze Horse, for example, or the body of a Mechanical Messenger Monkey, creating a clockwork robot with human-level intelligence housed inside a non-human body. Even weirder custom jobs are possible: mechanical dogs, mechanical octopi, mechanical insects... whatever you can tinker up, really. The more conservative Brass Folk disapprove of such experimentation, insisting that the Cogwheel Sage gave them human shapes for a reason, and that each new generation should imitate her prototypes as closely as possible; but many others, especially those whose association with the Steel Aspirants has given them a rather freewheeling approach to radical body modification, take a more liberal attitude. If a given Brass Man or Woman decides they wants their 'child' to be a giant mechanical frog, what business is that of anyone else?

So here are the rules for playing them.

All Clockwork Beasts have the following traits:
  • You gain a bonus to all your to-hit rolls equal to your level.
  • You gain 1d8 hit points per level (except large clockwork beasts - see below).
  • The whirring and clanking of your heavy brass body makes a hell of a lot of noise. Your enemies are never surprised, and you always fail any attempts to move silently.
  • You do not need to eat, drink, or sleep, and you are immune to poison and disease. 
  • You need winding up in order to function. All clockwork beasts have steam-powered auto-winders, normally built directly into their bodies at a point where they can easily reach it with their paws or mouths; when fed a supply of wood or coal, these auto-winders will spin rapidly, turning the beast's key in the process. They must sit still during the winding, or else they risk damaging their delicate internal machinery. One hour's auto-winding will power three hours of activity. If fuel for it is unavailable, the key may be turned by hand, but doing this takes six times as long, is amazingly boring, and risks causing strain injuries. For obvious reasons, they cannot wind themselves up.
  • When you have been wound for a number of hours equal to your Constitution score (thus permitting three times your Constitution score in hours of continuous activity), your main-spring is fully wound and further winding has no effect. If you reach the end of your 'powered' time without having a chance to rewind, you can stumble on for one extra hour, getting slower and slower: you have -4 Dexterity and Strength during this time. At the end of this extra hour, you shut down entirely until rewound. 
  • Your paws (or tentacles, or whatever) can be unscrewed and replaced with a pair of  human-like clockwork hands which you carry with you, allowing you to perform tasks requiring opposable thumbs. Unscrewing one paw and replacing it with a hand (or vice versa) takes five minutes. (This is to ensure that the clockwork beast can eventually build itself clockwork 'offspring', if it so desires. Building a beast without access to hands would be like deliberately sterilising your child at birth.) 
  • You do not feel pain. Normal healing does not help you, but as long as you have your hands on you can repair yourself when damaged, regaining 1 HP per day for field repairs carried out on the march, and 3 HP per day for a day spent doing nothing else. These numbers each rise by 1 if there is someone with a technology bonus of 3 or higher around to lend a hand. 
  • If you are reduced to 0 HP, you are too badly damaged to be repaired in the field, but with the right tools and expertise you can still be repaired in a well-equipped workshop, and will retain your memories and personality unless your clockwork brain has also been damaged or destroyed. 

Large clockwork beasts (e.g. clockwork lions, clockwork bears, clockwork horses, etc) have the following additional traits:
  • You must have a strength and constitution of at least 12 to play a large clockwork beast.
  • You cannot use weapons or armour, but you have a natural AC of 15, and inflict 1d8 damage with your huge, heavy claws. (You can have a gun built into your body, but unless you have your hands on you'll need someone else to reload it.)
  • You gain 1d10 hit points per level instead of 1d8.
  • You are huge, heavy, and enormously strong: capable of smashing light wooden buildings and furniture to splinters, and doing serious damage to heavier ones. A man-sized character could ride you. A swivel gun could be mounted on your back. (You couldn't fire it, though.) You can smash anything that a large metal animal should be able to smash, with no roll required. 
  • You can carry four times as many objects as a human with the same strength score.
  • You gain a +1 bonus to technology rolls.
Smaller clockwork beasts (e.g. clockwork wolves, giant clockwork rats or mice, etc) have the following additional traits:
  • You cannot use weapons or armour, but you have a natural AC of 14, and inflict 1d6 damage with your metal teeth and/or claws. (You can have a gun built into your body, but unless you have your hands on you'll need someone else to reload it.)
  • You can run twice as fast as a human, although doing this unwinds your spring at double normal speed. (If you are a clockwork frog or similar amphibious design, this is replaced by an ability to swim at double normal speed.)
  • You gain a +1 bonus to REF saves.
  • You gain a bonus to technology rolls equal to half your level, rounded up.

Clockwork insects (e.g. clockwork spiders, giant clockroaches, etc) have the following additional traits:
  • You cannot use weapons or armour, but you have a natural AC of 13, and inflict 1d4 damage with your metal fangs. (You can have a gun built into your body, but unless you have your hands on you'll need someone else to reload it.)
  • Your legs end in sharp metal hooks, allowing you to climb along walls or ceilings as easily as the floor. 
  • You gain a +2 bonus to REF saves.
  • Once per day per level, you can use your bite to inject a dose of corrosive venom, inflicting an extra 2d6 damage (FORT save for half).
  • You gain a bonus to technology rolls equal to half your level, rounded up.

Clocktopus by Westfalia miniatures.

Clockwork octopi have the following additional traits:
  • You cannot use armour, but you have a natural AC of 14, and inflict 1d6 damage with your metal tentacles. You can also use these tentacles to wield melee weapons and/or shields, but you cannot make a weapon attack and a tentacle attack in the same round.  (You can have a gun built into your body, but unless you have your hands on you'll need someone else to reload it.)
  • You can swim twice as fast as a human, although doing this unwinds your spring at double normal speed. You can also climb just about anything that will support your weight.
  • In an emergency you can just flip out and start thrashing your metal tentacles around randomly. Everyone within 5' of you must make a REF save or take 1d6 damage, and any fragile inanimate objects nearby will be smashed to pieces. 
  • You gain a +1 bonus to technology rolls.

Friday, 5 August 2016

History and anachronism in RPGs

Portrait Of A Safavid Nobleman, 17th c (agha khan museum):

According to my original post on the setting, ATWC is based on 'early modern Central Asia'. I'm pretty bad at restricting myself to Central Asia proper, as posts based on places like Azerbaijan and Vaygach Island and Yakutia will demonstrate; but what about the early modern period? Exactly which period of Central Asia's history is ATWC supposed to be based on, anyway?

This question has about three different answers. The overall technology level, clockwork robots and airships aside, is pegged to the end of the 17th century, but this doesn't match up with the implied political landscape: by 1700 Siberia and Mongolia had mostly been conquered by Russia and China, respectively, whereas ATWC presents the various steppe khans and taiga clans as still being independent. So the political setup is closer to Central Asia in 1600; but this, in turn, fails to match up with the fact that ATWC presents the Great Road as still being the primary artery of trade between the east and west, whereas by 1600 the real world Silk Road was in steep decline, rendered largely obsolete by the opening of direct maritime trade routes between Europe and Asia. The Great Road in ATWC is closer to the Silk Road in its late-medieval heyday, during the period of Mongol rule; but that doesn't match up with either the political or the technological contexts. In practise, then, ATWC is self-consciously and aggressively anachronistic in its use of Central Asian history. It's not as bad as a lot of D&D settings, which will happily place an ancient Celtic druid, a Viking warrior, and a swashbuckler from Renaissance Florence alongside one another as citizens of states which are described as medieval monarchies, but actually seem to function like eighteenth-century nation-states with twenty-first century moral norms. But it's not great, either.

Of course, ATWC isn't set on Earth; it's set on an unnamed world whose history has been mangled by untold centuries of magical meddling and the unwise large-scale production of clockwork murder robots, so it's not exactly surprising that the details don't quite sync up. It's inhabited by talking bears and people made of solidified sunlight and people with clockwork computers stapled to their brains, so strict historical realism is obviously not its highest priority. At the same time, however, it is attempting to evoke a certain time and place, however vaguely defined; my descriptions of the setting as 'early modern' and 'Central Asian' may be imprecise, but they are not (I hope) completely meaningless. So where does one draw the line?

Turkish Warrior Woman:

I've been gaming long enough to know that the number of players willing to absorb large quantities of information about campaign settings, whether historical or imaginary, is vanishingly (and probably mercifully) small. If much of the world of ATWC is rather vague, full of imprecise markers like 'the steppe khanates' rather than specific lists of polities, it's because, in my experience, that's all most players will ever want or need from a setting; they'll say 'Oh, yeah, those Mongol guys' and take it from there. Try to talk to them about Mongols and Oirats and Buryats and their eyes will glaze over, and at the end of it all they'll still just be thinking of them all as 'those Mongol guys'. At the same time, though, unless you're playing in a deliberately absurdist style, I think that most players want a world which at least feels as though it makes sense. Suspension of disbelief is a subtle thing, which operates largely at an intuitive level, and one advantage of drawing upon history is that it gives you a set-up which you know could exist, because it did exist. Maybe no-one at your gaming table has the kind of specialised historical knowledge to know why certain kinds of state formation accompanied certain forms of technological development: but they will know that knights and castles go together, and games can and should take advantage of that.

Then there's the issue of player expectations: roleplaying is a collaborative exercise, and that means that the game-world which matters is always the one that develops, in play, through the shared understanding of all participants about the fictional world their characters inhabit, rather than the one that sits in the GM's notebooks. Very often different players will have slightly different interpretations of this shared world, and that's OK; but if they have very different interpretations about how the world around the PCs is likely to react to, say, casual acts of questionably-justified violence, then that's likely to cause problems in play. Having a stable historical reference point gives players and GM alike some kind of shared basis upon which to build their expectations. You don't have to be a professional historian to know that a setting modelled on Dark Ages Finland is going to place different restrictions on what PCs can get away with than a setting modelled on 1930s New York.

I'd suggest, then, that unless you're group is actually serious about using RPGs as a way to explore historically accurate settings - which is something I've heard legends about, but never actually seen - then anachronism really only becomes an issue at the point where it generates confusion for the players. Put the PCs in an ancient Rome knock-off, and they pretty much know where they stand: there are legions, gladiators, slaves, orators in togas, temples to different gods, probably an emperor, and so on. Put them in a Victorian London knock-off, and they'll likewise have some idea what to expect: there are guns, policemen, factories, workhouses, newspapers, probably some kind of monarchy, etc. Tell them 'it's basically ancient Rome but with robots' and they'll deal with it, because they'll understand that the robot centurions, robot vestals, robot gladiators and so on are subsumed into the general ancient-Roman-ness of the setting, their presence not really disrupting the basic assumptions shared between players and GM about how the fictional world generally works. But a city which aggressively mixes up elements of Ancient Rome and Victorian London is going to leave them confused and off-balance, never sure how they should be responding to situations or how situations are likely to respond to them: and unless that confusion is something you're actually aiming for, that's probably not a good thing.

Pun Lun - Two Chinese Soldiers:

What does the early-modern-ness of ATWC actually mean? It means that PCs have flintlock weapons. It means they drink coffee when they're tired and gulp down laudanum when they're in pain. It means they read printed books and navigate with the aid of dry magnetic compasses and use spyglasses to check what's raising that distant dust-cloud out there on the steppe. All of those things create expectations in the minds of players. They might be fuzzy on the details, but they'll know that their musket-wielding, coffee-swigging PCs don't belong to the same world as Genghis Khan. Some of this knowledge will be explicit, but a lot of it will be implicit, a generalised sense of the kind of world which those things imply, and of the kind of lives their PCs are likely to be able to live within it. Anachronisms which don't interfere with that are probably fine; but anachronisms which do interfere with it really need to add something worth having to the setting in order to earn their keep.

This is why I've tried to make sure that the more aggressively anachronistic parts of ATWC - the walking houses, the mecha, the Brass Men, and so on - are all subordinated to the general early-modern-ness of the setting. This world is not industrial: its clockpunk technology is all the work of individual artificers tinkering away in workshops, personal and artisanal rather than standardised and mass-produced. The walking houses get used in the same way as any other form of caravan. The mecha are simply ultra-heavy infantry in some despot's army somewhere. The Brass Men are basically just another ethnic minority who happen to be made of metal and gears. As a result, they hopefully add colour (and robots) without confusing the overall sense of what kind of world this is, and what kind of things tend to happen in it.

That way, if and when you bring in real anachronism, Expedition to the Barrier Peaks style, it'll have the impact it deserves!

Sunday, 31 July 2016

These are free and also good

I have something of a weakness for free gaming modules. Whenever I go onto RPGnow to buy something I tend to also come away with a bunch of free pdfs, which build up and build up until I have a great pile of them; then I download them and skim them all in a blur of caves and ruins and dungeons with goblins in them. Most of them aren't that great, but a few really stand out; so I thought I'd flag a few of them up to bring them to other people's attention.

All of these are either freely available or 'pay what you want', at least at time of writing. Get them while you can, because PWYW products have a habit of suddenly acquiring fixed price tags after they get popular...

Dungeon of Signs: Gus L has produced a whole series of excellent adventures in pdf format, freely available on his blog. They're all well worth reading, but 'Prison of the Hated Pretender', 'Along the Road of Tombs', and 'The Dread Machine', are outstanding: dark and atmospheric and powerfully imagined throughout. Just steel yourself for a lot of dead PCs!

The Fungus Forest: It's not going to blow anyone's mind with its sheer originality, but this adventure module is a very solid example of OSR design principles in action: a subterranean forest full of weird factions and weirder individuals, almost all of which can be negotiated or allied with. Could make for several sessions of very enjoyable play.

The Caves of Moreau Country: This dungeon has a random-layout-generation gimmick, but that's honestly the least important thing about it. It's dark and vivid and sad and has some rather nice black and white art. It's also surprisingly faithful to the vision of The Island of Doctor Moreau itself.

Better than Any Man: I still think this is Raggi's best work, and he's giving it away for free. It's Lamentations, so expect cannibalism and dead babies, but if you're not put off by the subject matter then this is a very good example of historical fantasy-horror on a truly epic scale.

The Ruined Hamlet: This is mostly a pastiche of B2 The Keep on the Borderlands, and it's much more 'traditional D&D fantasy' than most of the others I've listed here, but it's done with heart and a pleasing level of attention to detail. Worth a look.

The Mysteries of Hollowfield: This is a series of short adventures set in and around a little woodland town, each of which is written by a different author. Unsurprisingly they're a bit of a mixed bag, but they mostly maintain a suitably creepy, Halloweeny tone, and the haunted house mini-adventure is a great example of using a few simple ideas and images to go a long way.

Madness of the Rat King: A 5th edition adventure, but should be very easy to convert to OSR D&D. This takes a concept which is cliched to the point of absurdity - a level 1 party gets hired to clear out some giant rats from under a tavern - and runs with it to such crazy lengths that it wraps right round into awesome again. By the time the flying rats with eye-beams attack, the cliches have been left a long way behind!

Friday, 29 July 2016

Pdf Phrenzy 2: Pdf Harder

I had a slow morning at work so I made pdf versions of my six recent B/X classes: Deep One Hybrid, Goblin, Half-Troll, Orc, Ghoul-Blooded, and Skaven Engineer. Which would make for a pretty great adventuring party, now I think about it, although the ghoul and the half-troll would constantly be fighting over who got to eat the monsters!

Pdf versions of my first five B/X classes - the Inquisitor, the Mesmerist, the Angel, the Sandsculptor, and the Patchwork Girl - as well as my introductory ATWC adventure, the Tower of Broken Gears, can be found here. Feel free to download or print anything you fancy for personal use...

Monday, 25 July 2016

So many monsters, so little time

I have been reading (well, skimming) a lot of D&D monster books over the last few months. Like, a lot. 

As a result, I have now seen what feels like approximately one million extremely minor variations on each of these monsters:

  1. A plant which comes to life and beats you to death / strangles you with vines / shoots thorns at you. 
  2. A statue which comes to life and beats you to death.
  3. A skeleton, ghost, or zombie with a stupid gimmick and far too many hit dice. 
  4. A mashup of two or more real-world predators.
  5. A race of big dumb humanoid brutes who love violence.
  6. A race of giant, hungry, alpha-predator monsters who love eating people.
  7. Innumerable pointless giant, golem, and dragon subraces. ('Marsh giants and bone golems are completely different from bog giants and skull golems!')
  8. Some random creature with snake parts, spider parts, and/or tentacles glued onto it for no fucking reason.
  9. A zillion different demon types which all boil down to 'it looks ugly and it wants to hurt you'.
  10. A variant on a classic monster but BIGGER and with MORE SPIKES.
  11. A variant on a classic monster but made of fire / ice / poison gas / thorns / knives / whatever.
  12. A mindless blob monster that dissolves people with acid.
  13. A giant heap of animated corpses all stuck together. 
  14. A sneaky thing that jumps out of a shadow and stabs you to death.
  15. A robot with a sword.
It brings home to me just how much of the conceptual territory for D&D monsters was soaked up by the original Monster Manual (and, to a lesser extent, the Fiend Folio and Monster Manual II): people setting out to write new monsters now are like settlers looking for new homes in territory where all the best land was taken forty years ago. The original Monster Manual was able to take every concept and present it in its purest form: footsoldiers of evil? Orcs. Big dumb thugs? Ogres. Terrifying boss monsters? Dragons. Everyone since has had to find narrower and narrower niches between the spaces which have already been taken. 'It's like a minotaur, but with six arms! It's like an ogre, but made of poisonous metal! It's like a troll, but with the head of a wolf!'

At the heart of this problem (like most others) is a basic tension between supply and demand. There's no limit to the number of monsters the game-as-written can contain: you can fill your shelves (or, more likely, your computer) with as many monster-books as you can be bothered to read. There is, however, a pretty sharp limit on the number of monsters the game-as-played can contain: regardless of how many monster ideas you have, you only need one session's worth of monsters per session. If every monster was equally useful, you'd expect the result to be increased variety; if the GM has a thousand monsters in his books, and only needs, say, five per session, then you could play weekly for almost four years without ever meeting the same monster twice. In practise, though, a glance at published modules, actual play reports, and everyone's real-life gaming experience confirms that this isn't what happens.

A handful of highly-popular monsters, almost all of them from the original Monster Manual or Fiend Folio, get used endlessly: goblins, orcs, ogres, skeletons, zombies, ghouls, elementals, lizard men, and so on. A second group of monsters, mostly just as old or very slightly newer, get used when GMs want something a bit more colourful: Githyanki, mind flayers, beholders, modrons, etc. And then all the rest - which, at this point, means something like 95% of all the monsters which have ever been published for D&D and its derivatives - is left fighting over the tiny 'novelty monster' slot that remains. Goblins and zombies have probably been used by every person who's ever run D&D for more than a few sessions. How many have ever used, say, the Bearhound? (It's an intelligent talking 10 HD bear with the teeth and tail of a wolf, which has the magical ability to make friends with other animals.) Two? Three? It's not even that bad a monster, as these things go; I can see one fitting very easily into a fae-themed adventure. It's just not good enough for most people to have any reason to use it instead of a dozen other things in actual play.

By the time they got to Monster Manual Five, they were really scraping the barrel.

On reflection, I think that modern monsters are most likely to be useful (and to be used) if they bring a whole scene or scenario with them, rather than being modular plug-ins that can be slotted into almost any game with a minimum of fuss. This may seem counter-intuitive, but let me explain with an example: in the course of my monster-manual-reading binge, one line I got absolutely sick of reading in monster descriptions was 'these undead creatures are often found guarding ancient tombs'. In theory, this means the monsters are easy to use: just drop them in as a guardian of whatever graves, mausoleums, sarcophagi, or whatever you have lying around your dungeon. In practise, though, it virtually guarantees that they never will be used, because there are already several hundred undead monsters which could do the same job, and honestly 90% of the time people will just use a wight or a wraith or a mummy instead. Whereas a monster which carries something more specific with it - a scene, a story, a cultural context, a narrative or an environment or an adventure which its existence generates or implies or requires - can be used as a kind of mini-module, something that someone might read and think: 'huh, I'd like to run that at some point', and which thus has a much greater chance of it making its way into actual play than it would if it was just Minor Lizard-Man Variant #432.

Take, say, the Moon Apes from Fire on the Velvet Horizon. They're cool and weird-looking - big red-black frog-ape-monsters with vertical mouths whose bite induces confusion and forgetfulness, making people deny the very wounds that they have just sustained - but if that's all they were, they probably wouldn't see play, because D&D has about a thousand weird-looking ape-monsters with special attacks in it already. But there's more to them than that: they're parasites who live in the bodies of dead cloud-titans, who swing down to the surface on loops of cloud to bite people and steal valuables and children, and then vanish back up to their lairs with their loot, leaving their victims so befuddled from the effects of their bites that they have no idea what's just happened to them. There's a whole implied adventure, here. Scene one, PCs come across a devastated and looted community full of people with weird bite wounds, none of whom is able to give a coherent account of what has attacked them. Scene two, PCs try to work out what the hell is going on. Scene three, PCs find a way up to the cloud-lair of the moon-apes to kill them and take back what they've stolen. Now, maybe you don't like the sound of that adventure, and that's fine; but if you do like it, and if you want to run it, then the moon apes will be an essential part of it, and as a result there is a decent chance that they will get used. Whereas without that context they'd just have been one more entry on a long, long, long list of monsters that might leap out from behind the next bush and try to kill your PCs, with no more chance of actually making it into play than any other. 

In nature, every organism is engaged in a Darwinian struggle for survival. The same is true of D&D monsters, except that what they're competing for isn't food and territory, it's use in actual play. A monster which brings something to the game, whether in the form of a vivid scene or an interesting tactical challenge, will get used more than one that doesn't; being used will grant it more exposure, which will lead to it being used by other people, and so on. The main ecological spaces are already taken: nothing is going to replace the goblin or the zombie any time soon, and just writing yet another 'big thug monster' and expecting people to start using them instead of trolls and ogres is usually going to be something of an exercise in futility. But there's no reason that new monsters shouldn't thrive within their own niche ecosystems if they're given the chance!