First up: the Creepy Crawlies.
What is Creepy Crawlies? A campaign of occult mystery, in which the PCs are "children of the night" dedicated to protecting the world from the true horrors of the universe. Creepy Crawlies are allied with an ancient order of monster-slaying canids called the Watch Dogs, and represent the first line of defense against the lingering ghosts of evolution. As the sorts of animals often summoned by the presence of nightmarish infestations, Creepy Crawlies are in a perfect position to infiltrate and, if necessary, strike first against both conventional monsters and the madness of the Neverspawn.
Character Options: Species most suitable to a Creepy Crawlies campaign include bats, black cats, black dogs, lizards, owls, rats, ravens, snakes, toads, wolves, and possibly even sentient swarms of spiders or other "bugs." All of the standard niches are available, along with a new niche, the Familiar (a spirit-possessed animal capable of using standard OSR magic, but in a different way than clerics and magic-users). Other possible new niches include the Psychopomp (an animal dedicated to escorting spirits of the dead to their final reward) and the Shapeshifter (do you really need an explanation for this one?).
- Beasts Of Burden by Evan Dorkin (author) and Jill Thompson (artist) (Dark Horse Comics): a group of neighborhood dogs (plus one cat) protect their unknowing humans from horrors of the occult (even teaming up with Hellboy at one point!).
- Thor by Wayne Smith: man's best friend confronts man's worst nightmare in this family dog vs. werewolf tale that became the basis of the not-terrible movie Bad Moon. The novel, told from the dog's point of view, is far superior.
- Cat: an RPG about house cats protecting their humans from monsters they can't see.
- Lamentations Of The Flame Princess Weird Fantasy Roleplaying by James Edward Raggi IV -- the versions of old-school magic found in this take on the OSR are ideally suited to a Creepy Crawlies game.
- Random Esoteric Creature Generator for Classic Fantasy Role-Playing Games and their Modern Simulacra by James Raggi IV from Goodman Games -- great for making Neverspawn monsters
- Realms of Crawling Chaos from Goblinoid Games -- a Lovecraftian resource for Labyrinth Lord and other old-school games
Evolution has a secret: extinction is not forever. The world is haunted by the angry spirits of species long gone, and worse, of those never born. There is a place -- the Lingering World -- where such terrors conglomerate and push against the Membrane between realms. Sometimes, they break through, desperate to either replicate unfettered, or annihilate all competitors.
In the Lingering World, two dread god-things vie for supremacy: the Winnower, embodiment of natural selection, seeks to eliminate all disorder and confine reality to an eternity of cold pattern and stasis; and the Progenitor, source of life unchecked, wants only to spawn without restriction or reason. Both of them birth broods of impossible form to people their eternal armies, and sometimes that battle seeps into our world.
The Progenitor is the source and protector of Neverspawn, beasts of illogical congerie and ghosts of lost possibility, phylogenies that might have been. Their only goal is to replicate and consume, invading all niches and supplanting all other life.
The Winnower's minions are more conventional, possessing anatomies that, while monstrous, still "make sense" to a terrestrial vertebrates' perceptions. Though not inflexible, their forms and powers are somewhat predictable, and this makes them easier to fight... in theory.
Monsters who serve the Winnower (sometimes unknowingly) pursue agendas that promote death, entropy, and extinction. They include many of the monsters of traditional gothic horror.
Creatures who serve the Progenitor have no standard form or appearance, unless they are members of Neverspawn cults from our own world.
Both god-things have human and animal servants, as well, and Creepy Crawlies often infiltrate their ranks to learn more about and subvert their plans before it's too late.
Creepy Crawlies adventures are often investigations of hauntings, disappearances, bizarre sightings, and other unexplained phenomena, climaxing in "lair-crawls" into the heart of the menace's stronghold, to confront, contain, or eliminate the beast on its own turf. Along the way, Creepy Crawlies will often use their talents to scare off humans and other animals, giving them a fright for their own good.
- Bloodless bodies have begun to appear in the area, leading the Creepy Crawlies to suspect the presence of a vampire. But they discover that it is, in fact, a shape-shifting giant trigonotarbid direct from the Lingering World, who has taken up residence in a dilapidated old house and is about to hatch its young upon the locals.
- The party investigates sightings of a cryptid, such as Bigfoot, the Chupacabra, a unicorn, or some other "impossible" animal. They discover that she is the last of her kind in our world, and is being stalked by terrible minion of the Winnower called the Eater of Last Things. Do the PCs help this animal-that-should-not-be, or do they help the Eater carry out its duty to evolution, risking their own deaths in the process?