The beast in the Chamber of Secrets is a Basilisk, an ancient creature feared by spiders and many other creatures. Its bite is fatal as its fangs are highly venomous, and its eyes are deadly, and seeing it instantly kills the victim. However, if its eyes are seen through a reflection, the person is petrified. The Basilisk was used by Tom Riddle, the heir of Slytherin to attack Muggle-born students at Hogwarts.