No one knows what arcane arts the Dark Eldar use to create their Crucibles of Malediction. Each crucible appears to contain the trapped spirits of psykers captured and tortured by the Dark Eldar. When released, these spirits hurtle across the battlefield unleashing a psychic cacophony that can drive an enemy psyker insane. A character carrying a crucible may use it in the shooting phase instead of moving or shooting. When the crucible is used the nearest enemy psyker must pass a Leadership test. Subtract -1 from the psyker's Ld if he is within 12" of the model with the crucible, and add +1 to his Ld if he is over 24" away.
If the test is failed the psyker is removed from play. No saves of any kind are allowed, and the psyker is killed no matter how many wounds he has. If the nearest psyker passes his Ld test then the next nearest must test, and so on until either all psykers have passed, or one has failed.
A crucible can only be used once per battle, and only one can be taken per army.