The FIRST RECORDED Basilisk was raised by Herpo the Wicked, a Greek mage, Dark and Serpent-tongued, who discovered after many experiments that if he left a chicken egg to incubate under the belly of a frog, a giant reptile with extremely dangerous powers would be born. The Basilisk has a shiny, emerald color and can reach up to fifteen meters in length. The male has a red crest on its head. Its venom is deadly, but its truly lethal weapon is its hypnotic gaze. Anyone who looks into its large, yellow eyes will die instantly. If it is adequately fed (it eats all mammals and birds, as well as most reptiles), the Basilisk can live to a very old age. Rumors say that Herpo the Wicked’s "pet" lived for nearly nine hundred years.

Basilisk breeding has been illegal since the Middle Ages, although, unfortunately, an offender can very easily deceive the inspectors of the Department for the Regulation and Control of Magical Creatures; it is enough to simply remove the chicken egg from under the frog’s belly and hide it. However, because Basilisks are generally uncontrollable and only the Serpent-tongued somewhat tame them, they are equally dangerous even to other Dark Mages. Fortunately, in the last four hundred years, there is no evidence proving the existence of Basilisks in Britain.