Great Ravens were huge birds sustained by magic and lead by the Matron, Crone. They were allied with the Tiste Andii, their roost was Moon's Spawn. They were said to have a wingspan of fifteen feet.
K'rul related how the Great Ravens had formed from the maggots eating the pieces of the Fallen One's broken body which littered the sister continents of Jacuruku and Korelri. In addition, Crone revealed their collective embarrassment regarding their origin.