Varghoulie (4e Creature)
From D&D Wiki
With a successful skill check, a player knows the following information:
Dungeoneering DC 15: A varghoulie's kiss is deadly in that it spreads a type of fever that kills its victim and turns them into one of their own horrid kind.
Varghoulie tend to act like bats. They flock together when there are more of them and can amass into swarms. They don't function well with other creatures like slow manes or upper-crust yugoloths, and so they are left as a sort of separate scourge for battle tactics.
Varghoulies look like horrible humanoid heads covered with rotten skin and boils, with glazed eyes of the dead. Their ears are replaced with wings that allow them to fly, and their teeth are replaced with wicked fangs.
Varghouilles will lie in wait for prey, attempting to ambush them. They will try to surprise and immobilize as many victim as they can with their shriek, and pick off the weak with their bite. Once a target is immobilized, the swarm attacks en masse with their teeth to tear targets apart, and also kiss the hapless targets to forcibly infect them.