In order: minimal, and none explicable/replicable. If there is a 'magic spell' it will result in your horrible death 100% of the time, although not always immediately.
No vampires; there may be things that drink blood but they have virtually no other points of correspondence with the nosferatu of penny-dreadful fiction.
No vampires; there may be things that drink blood but they have virtually no other points of correspondence with the nosferatu of penny-dreadful fiction.