Darkening

The Darkening was the name given to a spell that cast shadows over the Silver Marches in preparation for the drow and orc invasion of that land starting in 1484 DR, which came to be known as the War of the Silver Marches.

Effects
The Darkening caused dark roiling clouds of a foul, smoke-like substance to cover the sky above the Silver Marches. During the day, this hid the sun, reducing daylight to the equivalent of a moonless night. At night, the stars were hidden completely.

History
The spell was given to the drow wizard Tsabrak Xorlarrin by the illithid Methil El-Viddenvelp by the order of Matron Mother Quenthel Baenre. While casting the spell, Tsabrak was said to have served as a conduit of Lolth, the first such occurrence since Yvonnel Baenre channeled Lolth when destroying House Oblodra in 1358/1359 DR.