Lilith's Crook is a demonic horn owned by Lilith.
Overview[]
Lilith's Crook was said to have been made from the horn of a goat that was devoured by Azazel. The Crook is said to be a Satanic version of the Shofar, an ancient musical horn typically made of a ram's horn, used for Jewish ritual purposes. Said shofar was also used to blast spirits like the Lilim away.
Despite its significance, Lilith rarely ever used it and has only done so a handful of times ever since its conception. Only Lilith is able to use the Crook though it is possible that other demons can be qualified as it was implied that her sisters - Naamah or Agrat Bat Mahlat - can use it.
Its most prominent uses was when she announced the breaking of the first seal i.e. Vergil escaping Hell and the second was the beginning of the Blackest Night. It was likely made to announce a grandiose event for the Inferno, a "promised day" so to speak that will give the demons their reign over Earth.