In Shar's domain of night I rest,
So dreams may show me how I'm blessed.
If screams of terror break my sleep,
Then Dendar sank her fangs too deep.
Dendar, the Night Serpent, is a colossal serpent who spent her time devouring the nightmares and fears of both mortals and immortals in hopes of bringing about the end of the world. Dendar was thought to have been created when the first mortal dream occurred, and she devoured the nightmares of the living ever since. Even the gods were not immune to her ravenous appetite for their dreams.
It was the Night Serpent who was thought to bring about the end of the Blue Age and usher in the Shadow Epoch by devouring the sun and plunging Toril into darkness and freezing temperatures.
Her enemies include an Ubtao-worshiping cult in the Cradle of the Gods who called her "Eater of the World." They believed she lived beneath the Peaks of Flame and would one day emerge through a gigantic, iron door to devour the sun if Ubtao failed his duty when the end times came. They believed it was their sacred duty to battle her.
Another group of Kelemvor worshipers instead saw it as their sacred duty to take the battle to her on the
Fugue Plane in order to siphon off the nightmares she had devoured; thus keeping her power in check and earning a certain, if well-earned, death.