Night hag

Night hags were incredibly evil creatures that lived in the Lower Planes. They were known for their mercilessness and ability to walk in the dreams of others. In the Fiendish planes, they were powerful creatures and the developers of the process that created altraloths, powerful unique yugoloths, but much more commonly known for being able to harvest larvae, which were used as currency in the Abyss, Blood Rift, and Nine Hells. They also had an affinity for nightmares.

Description
A night hag stood between five and seven feet tall. She had ugly features, blue-violet skin, and burning red eyes. Many night hags had horns of some sort. Their hands ended in impossibly long fingers with sharp talons. The body of a night hag appeared to be skeletally thin; however, they possessed a great strength fueled by the hatred of all beautiful things.

Combat
A night hag had an array of magical powers, and could transmit a disease called demon fever by biting a victim. Night hags were also able to torment chaotic or evil individuals by invading their dreams, by turning ethereal using a special item called a "heartstone". This process eventually transformed the victim into a larva unless some force capable of affecting ethereal beings put a stop to it.

Society
Night hags, being exclusively female, could only reproduce by mating with a male member of another species, typically a member of a civilized race. The hag often slew her mate. The child born looked like a normal member of her species with black or blue hair and was often given into foster care by the hag disguised as a normal woman. When the young girl reached puberty, the mother night hag might visit the child several times and, after several rituals, transform her offspring into another hag. Interrupting one of the thirteen rituals ceased the process of transformation.

For reasons unknown, some night hags gave birth to accursed offspring known as dusk hags.

Religion
Cegilune was the goddess of the night hags.

History
Night hags were once native to the Feywild, but their extreme evil led to their exile to Hades, from where they spread throughout the Lower Planes.