Spoilers follow.

Elven sorceress arrives in isolated region: she charms and slays some locals, animating them as zombies; a dupe moves the remains of a saint, potentially releasing trapped fire demons; the sorceress seeks a pact with the fire demons. PCs may be agents of/employed by the local abbey, investigating the disappearances of villagers.

Best described as an adventure framework rather than a full adventure; there are no maps. The village, abbey and fens are described in sufficient detail to run interactions with the PCs. Would definitely benefit from an introductory paragraph summarising what is going on, to help the referee: you have to wait until page 10 for the section Elf Maid's Plot. Should be easily adaptable to many systems. For WFRP, fire demons could be replaced by (intelligent) Flamers, the elf by a Druchii.