"There is none more curious or more deadly than the Basilisk"

Basilisks have been a part of European mythology for thousands of years.  They come in different forms, some resembling snakes and others closer to cockerels.  They are said to be born from the egg of a toad, hatched by a cockerel.  Other serpents flee for safety when they hear the first ‘hiss’ of a basilisk, even if they are in the middle of a meal.

In mythology there are different versions of how the basilisk kills. Some say that this King of Serpents burns everything it touches, others that its breath poisons the air.  Still others claim its blood is so potent that if a knight drives a spear through it the poison will kill not only the knight but also the horse he is riding. Some believe that a basilisk, like the Medusa, is capable of turning anyone who looks into its eyes to stone. 

Supposedly a basilisk can be killed by the crow of a cockerel, or by holding a mirror up to its "baleful gaze".  Travellers in the Middle Ages were said to carry cockerels with them as protection against basilisks.