The basilisk is said to be a deadly magical reptile described as the "king of serpents" in European legends. Being described as a serpent in most texts, it is generally accepted to be some kind of snake, though several descriptions and images of the basilisk reveal that the creature has eight legs.
Part of the reason the basilisk is referred to as "king of serpents" is the crown-shaped crest it supposedly sports atop its head. It may also be known as a "king" out of fear. Basilisks supposedly have the ability to kill any creature instantly with a glance. Anyone that looks a basilisk directly in the eye will immediately keel over dead. As well as its deadly stare, basilisks supposedly ooze venom from their bodies and leave a trail of it wherever they go. Basilisk territory can be readily identified by dead animals and plants surrounding its lair, killed off by the creature's potent venom.
Supposedly, the basilisk's weakness is the odour of the common weasel. It seems that the stench of weasel urine is fatal to the basilisk.
- In J.K. Rowling's book Harry Potter and the Chamber of Secrets (1998) and its film adaptation by Chris Columbus (2002), a basilisk appears as a major plot element. The event and the beast's species are subsequently referenced multiple times in the Harry Potter franchise. This gigantic depiction of the monster is described as having tremendously venomous fangs and as instantly killing everyone who directly crosses sights with it, and petrifying those who indirectly see its eyes, and can be mentally controlled by Parseltongues, especially (in the case of the book's specimen), by the Heir of Salazar Slytherin (Lord Voldemort). It Is also explained that basikisks (also known as Kings of Serpents) are created by having a toad hatch a chicken egg (something first fine in ancient Greece by wizard Herpo the Foul) and die if exposed ti a rooster's song.
- It is possible that basilisks are a unknown type of massive snake.
- The cockatrice is similar to the basilisk in many ways, although it possesses both reptilian and avian features.
- One theory is that it is a dragon-anaconda hybrid, hence the draconic head and snake body.