REJECT MODERNITY, EMBRACE FIEND FOLIO

I was flipping through my copy of the Fiend Folio, which in my opinion is one of the most creative and unique sources of monsters in the history of Dungeons and Dragons and similar games (though I would probably put the Arduin Grimoire and All the World's Monsters on that list too), and I thought about how interesting it would be to put together a game/campaign/world using only the Fiend Folio as your main source of creatures for the game. I'm willing to stretch it to include real world animals but other than that, and any monsters which are explicitly mentioned in the text of the Folio but are not statted up therein (for instance lizard men, who are mentioned in the description of the lizard king), no creatures from other sources. So uh, here's that I guess. At present its mostly a mental exercise but I might expand on it in future, maybe statting up Fiend Folio monsters and player types for the more B/X derived rules that I'm more into.

So, where else is a good place to start but talkin' about PLAYER RACES, since the Folio does have a good number of intelligent creatures that would be suitable for such a thing. Most notably however, since we're making this world using only creatures from the Folio, I'm ruling no humans! Technically this goes against my thing above about allowing monsters mentioned in monster descriptions, but I don't care about this one, I think it would be most interesting to just have no humans.

Perhaps, however, humanity did once exist in this world, which uhh let's call it Teufelland, german names are always fun and Teufel means devil which is basically the same as fiend. But yes, perhaps humans did once exist, but disappeared rather suddenly, leaving behind a mess of ruins and towering spires. I imagine a large abandoned metropolis in a wilderness recovering from destruction, now inhabited by wholly nonhuman races.

Looking over the monsters with intelligence of at least Low (which is uh, a lot), and eliminating stuff like demons and dragons and spirits and slaadi, you still end up with a list thats a biiiit too unwieldy to really use as a list of playable races. So how about we group 'em together and narrow it down!

The FF ettercap... one of my fav monsters

Humanoid types:

Dark Elves (technically other kinds of elves are mentioned in their description but I think its more fun to just use drow)

Svirfneblin (same thing as above but with gnomes, I'm only gonna use deep gnomes here tho)

Goblins (they are mentioned in the description of the Nilbog and I kinda like them)

Githyanki

Githzerai

Animal People types:

Aarakocra (really wish there was a better name, its a bit of a mouthful honestly)

Bullywug

Crabman

Ettercap

Firenewt

Kenku

Kuo-toa

Lizardmen (mentioned in the description of the Lizard King and I rather like them)

Quaggoth

Tabaxi

Beautiful flies : )

Even this list is a bit long, but a picture starts to reveal itself... a lot of creatures that are stereotypically inimical to human civilization, a lot that live underground, and a Lot of animal people. A final list of playable races I think would be below... and note that I'm emphasizing playable because I have some ideas for some of these other folks!

Bullywugs

Crabmen

Dark Elves

Deep Gnomes

Firenewts

Goblins

Kenku

Lizardmen

Having these eight as the playable races provide a really really interesting array of concepts and sources of inspiration, and a pretty even divide between the more human-like races (dark elves, deep gnomes, goblins) and animaloids (bullywugs, crabmen, firenewts, kenku, lizardmen). I imagine this world as almost a Gothic Gamma World, a land of imposing castles and dreary rocky outcroppings and long abandoned sorcerous laboratories. Perhaps there is a society made up of dark elves, deep gnomes, goblins, and kenku that lives underground and in the shadows of the cities above. Maybe the underground can be the default core of society! Wouldn't it be interesting for deep cities in caverns lit by glowing mushrooms and crystals to be the "civilized" world while the towering spires above are the dangerous dungeons?

Maybe infravision, since a lot of these races have that in AD&D, would be the default way to see the world, with bright light being the vision hazard. I think it would be very fun to intensify infravision so that creatures with it flat out cannot see in bright light at all, and must bring darkness with them, or bring their own underground light sources... One of the big benefits of the firenewts and crabmen could be them having the inverse, with brightvision that helps them work around the light hazard that the dark elves and goblins have to deal with.

Honestly it probably looks a lot like Yharnam from Bloodborne

So this is an inverted megadungeon, with the levels getting more difficult as you march up and your homebase being a city or town underground. Light is a problem to work around, and darkness is your friend. 

A ruin haunter from All Tomorrows
by CM Kosemen

The githzerai and githyanki are explicitly descended from humans according to the Fiend Folio, and I did have them on my intelligent human-types above, but I think it would be most interesting to keep them as non-playable creatures. Perhaps they are the descendants of humans from the far future, having diverged into two distinct species and ended up in outright war with one another. They traveled back in time to the post-human age that the game is set in, perhaps one fleeing the other across the time space continuum, and now they are here, battling it out in the upper spires. They wield demons and psychic abilities and future tech and well I just think that would be really fun, it is a dynamic overlay that makes the inverted megadungeon even more interesting.

Perhaps the visuals of the githyanki and githzerai could be reinterpreted (although I will admit I love the ghoulish way the githyanki look)... maybe taking a cue from actual hypothetical future human evolution like CM Kosemen's All Tomorrows?

So uhh yeah I guess this is where I'll stop for now, with a list of hypothetical playable races, a conceptual game environment, and a conflict overlaying it all to make it interesting. If people like this post I'll probably continue it, I think its a really fun and interesting concept! The Fiend Folio doesn't get enough love, so I want to give it a fair shake.