Dangerous Encounter: Well, Well, Well

The PCs are summoned by the town's mayor (or village chieftain, depending on where they are at the time) to meet with the local medicine man. This post-cataclysmic physician asks the party to retrieve a few wineskins of “sweetwater” for his medicine chest. He explains that sweetwater is a naturally occurring liquid -- a heavily mineral-laden water -- that acts as a poison antidote for all poisons of class 7
or lower. For higher level poisons, sweetwater will halve their damaging effects. The curative powers of this substance cannot be stressed enough, as the area is teeming with poisonous insects and creatures.

The medicine man knows of a well where some sweetwater can be retrieved, and he only needs 5 wineskins to refill his supply. After presenting the PCs with the 5 skins they need for transport, he tells them that any additional sweetwater they retrieve is theirs to keep, sell, or whatever they'd like to do with it. The medicine man draws a crude map on a scrap piece of paper, pointing out the paths they need to take to reach the well. He says the well is a simple hole in the ground about 8 feet across covered with a simple wooden lid to keep animals from tumbling in. The well is located in the middle of an open field ringed by some sparse trees, so the party should be able to see trouble approaching while they complete their task. 

The well is simple to find as the map takes the party right to the field about 4 miles away from their starting point. The field is off the path, and a line of trees ring the edges of the field about 200 yards away. The wooden lid can be seen near the center of the field just as described. However, scattered around the well are 6 Giant Carnivorous Flies (MF rules, page 72). They seems to be feeding on the corpse of something (or someone) that got close to the well. 

Giant Carnivorous Flies (6) (AL N, MV 90' (30'), Flying 180' (60'), AC 6, HD 2, #AT 1 (bite), DM 1d8, SV L1, ML 8, mutations: gigantism)

When the party starts to approach, or if anyone fire at them with a ranged weapon, the Carnivorous Flies will fly up and around in random directions, homing in on the party. They'll swoop in for the attack, landing and biting a PC before flying off again to circle around for another attack. Once the flies are dealt with, the PCs can approach the victim and the well.

The well's lid can be lifted by two party members (it's quite heavy). Once lifted, the PCs will find nothing underneath. No hole, no well, just ground...as if the lid was laying on the bare ground rather than covering an opening.

The victim is about 30 feet from the well's lid and, unknown to the party, he is laying within a few feet of the actual well. A Giant Trapdoor Spider (MF rules, page 97) happened upon the well's lid and, once it tossed it aside (to where it now rests), the Spider climbed into the well to use as a new lair. As a Trapdoor Spider, the monster wove a new "lid" out of grass, weeds, sticks, and webbing, creating a very well-camouflaged trap for unsuspecting victims.

Giant Trapdoor Spider (12) (AL N, MV 60' (20'), AC 6, HD 3, #AT 1 (bite), DM 2d6/poison, SV L2, ML 8, mutations: gigantism)

Anyone who gets within a few feet of the trapdoor has a 1 in 6 chance of spotting the hidden trap. If they fail the check, the victim will be caught by surprise as the Giant Spider leaps from its hidden lair, grabs the victim, and yanks them down into the well. The Giant Spider will get one free attack and, if it successfully bites the victim, it will do 2d6 hit points of damage and inject a class 12 poison. Failing a save versus poison means death for the victim in 3 turns, and a successful save results in 1d6 hit points of damage. Hopefully the rest of the party saw what happened, otherwise the victim will be all alone and trapped in the confined well with the Giant Spider!

Once the Giant Spider is killed, the party can retrieve the sweetwater from the well. There is enough to fill 8 skins with the substance. If the party investigates the victim, they can see he had been bitten by the Giant Trapdoor Spider, but managed to not be pulled into the well. However, he died from the poisonous bite. The body is carrying 67 silver pieces and 66 gold pieces. He is also armed with a Bygone revolver pistol with 3 shots left. Each will do 1d10 hit points of damage.