The magus must first acquire a weasel, either wild or domesticated matters not, and feed it the meat of a chicken or snake that has been soused in vinegar while casting this spell. Between the time of casting and the next dawn the weasel acquires a compulsion to attack any basilisk it sees or smells. A basilisk bitten by the enchanted weasel must Save vs Death with a [dice] penalty or be instantly slain.