Unforgivable Curses: The three Unforgivable Curses are Avada Kedavra, the Imperius curse and the Cruciatus curse. Unicorn: Mythical white horse-like creature with golden mane and a golden horn sprouting from the head. Innocent, beautiful creatures. Tail hair and horn can be used in magic. Dark wizards have been known to kill unicorns and drink their blood; this will sustain the life of the drinker but at a grave price. Unspeakable: Employee of the Department of Mysteries. No one knows what they do. Harry Potter and all related indicia are trademarks of Warner Bros. © 2002 Warner Bros. All Rights Reserved. Harry Potter Publishing Rights © J.K.R.