PRIMITIVE: The Serpent Strikes
You and your fellow adventurers are relaxing in the inn spending hard won coins when you're approached by a secretive little man. He says he's an ex-cultist of The Fang and wants your help stopping an upcoming ritual, which will corrupt the village transforming the people into monsters.
He offers each of you a magic pendant that bestows protection from poison and a map to the cultists' treasure trove. All you have to do is stop the ritual, destroy the cursed grimoire, and collect the treasure.