Master of Ravens: A 5th Level Adventure for 5th Edition

Long ago, the wizard Elrad the Wise saved the town of Dunkirk from a demon known as Zazzarak. The demon had been summoned by a small cult to possess the people of the Dunkirk and turn them into mindless monsters. Luckily for the inhabitants of the small village, Elrad was able to destroy the cult and banish Zazzarak from the material plane. Unfortunately, the cursed idol that the cult used to summon the demon in the first place was never located, and its power has been slowly corrupting the flora and fauna around the village in the decades since.

Recently, this corruption has spread to the local bird population. A flock of ravens passing through the area on their way south for the winter were corrupted by the idol's presence. Sprouting a third eye, they now harass and hinder those who travel the area. Some have even outright attacked the villagers. The true danger, however, comes at nightfall, when their eyes glow red and a malevolence takes over. That is when the birds transform into larger monstrous versions of themselves and directly assault the village and its inhabitants. Unless someone can locate and destroy the source of the corruption, the demonic evil will continue to plague the lands.