My September Challenge short adventures feature horror themes and may not fit the tone for your game. Horror moments create memorable stories and generate strong antagonists because of the emotional engagement they create; like I say in Defending the Horror, horror gives your players something worth fighting. But if mixing horror and D&D isn't your thing, you might want to skip these.
Our core rules use a mix of LOTFP, Labyrinth Lord, and LL Advanced Edition Companion. Some of these entries will also reference Goblinoid Game's Realms of Crawling Chaos.
Horror Adventure 1 - You Are What You Read
Traveling through the pastoral outskirts of a town, the characters encounter a starving urchin at the crossroads.
SETTING THE SCENE
The starving urchin cries out in pain; he lays on the ground in hunger and weakness, begging for food and assistance getting back to town. One can't help but notice his distended belly beneath his tunic.
The urchin dies in 20-40 minutes as black eel-like gut worms (see below) burst out of his abdomen in a horrible explosion of viscera. 2-5 gut worms wriggle free to attack any nearby people. Feeding the urchin per his request speeds up the rupture time by 10 minutes; a Cure Light Wounds masks the symptoms, delays the rupture time by 10 minutes, and allows him to walk on his own. If you're playing this without a map, the urchin is found a half hour outside of the town, and let the dice fall. If the group is close to town, it's reasonable they'll reach a surgeon or doctor before the rupture. The image of the rupture occurring as a surgeon or doctor begins an examination, with the urchin splayed on a table, is really quite horrible.
There are two clues to lead the group further into the mystery; a helpful hobo (beggar) waits near the entrance to the town, the friend of the starving urchin. If the helpful hobo sees his friend's condition, he'll remark how he warned the urchin not to try and rob the old alchemist; "He weren't like this yesterday when he first went out there - not all skin and bones like he's been sucked out." Alternatively, the group might find gold coins and potion vials in the urchin's belt pouch; the vials are sealed with the imprint of a famous local alchemist and mage. (The DM can roll randomly for 2 potions).
The alchemist's small villa is eerily quiet and deserted. The alchemist is dead; in the vaulted study, the old alchemist mage has hung himself. Dried blood and viscera litter the floor beneath the dangling corpse, and the man's abdomen is blown out like the urchin's. Knowing the grim fate that awaited him, it appears the mage took his own life first. There will be 1-4 gut worms lurking nearby, squiggling out to ambush the characters. On a nearby table is a wicked grimoire opened to a book marked page; a curse called the Touch of Shoth-Mosha is showing. A player that casts Read Magic to read the page must save vs spells or be cursed as well!
The grimoire sits on a sheaf of brown wrapping materials as if it were recently delivered to the alchemist and then opened. Was it an enemy or rival that sent the book to him? If you want a moral dimension, the grimoire was sent by a rival wizard as a cursed trap and the party can seek out this foul villain, perhaps by finding the courier in town. A bleaker theme is that the alchemist was the victim of knowledge 'man wasn't meant to know' and brought this on himself. The grimoire may have additional spells; I suggest using the Realms of Crawling Chaos tome rules to create the Tome of Shoth-Mosha.
If lower level parties don't have access to Remove Curse, they face the grim prospect of having to slay the infected to stop the spread of more worms. A grim choice indeed if a PC has been cursed!
To increase the challenge for higher level groups, I suggest providing clear evidence at the villa that some of the worms infected a deer, or perhaps the mage's horse; the group will need to cover a lot of ground to catch up to the infected animal before it spreads the curse to the next county.
These horrible things are the spawn of a blasphemous outer god, called into the mortal world by the Curse of Shoth-Mosha. They appear as 3' long blind, wriggling black eels, with lamprey like mouths; they detect life forms out to 60'. The bite does minimal damage but the victim must save vs poison or be infected with the curse; if the curse is passed on, the worm that bit the victim immediately shrivels and dies as the curse essence passes into the victim and begins to grow more worms. Infected hosts grow 2-5 gut worms with an incubation of (24 + 2d6 hours). Fully grown worms rupture the victim's abdomen, killing them instantly, and then the worms begin hunting new victims. The worms can be cured with Remove Curse, kept at bay with Protection from Evil, and the use of other curative spells will delay the incubation as the DM sees fit.
Locales: a town, an alchemist's villa
NPCs: the starving urchin, the helpful hobo, a doctor/surgeon/healer
Monsters: Gut worms!
Artifacts: A grimoire - the Tome of Shoth-Mosha