Slytherin, according to the legend, sealed the Chamber of Secrets so that none would be able to open it until his own true heir arrived at the school.
The heir alone would be able to unseal the Chamber of Secrets, unleash the horror within, and use it to purge the school of all who were unworthy to study magic."The Chamber of Secrets was created under the Dungeons of Hogwarts School of Witchcraft and Wizardry during Medieval times by Salazar Slytherin, who disagreed with the other Hogwarts founders on the merits of Blood Purity.
The first message read: "The Chamber of Secrets has been opened.
Enemies of the heir, beware." Opening the Chamber of Secrets let the Basilisk come out and made people look at it in different ways, which Petrified many students, including Colin Creevey, Justin Finch-Fletchley, Penelope Clearwater, and Hermione Granger, as well as the Ghost of Nearly Headless Nick and Argus Filch's cat, Mrs Norris.
They were later restored to their proper states through the use of Mandrake Restorative Draught. On 29 May, 1993, Ginny was taken down to the Chamber to die, while Riddle intended to feed off her life force in order to become fully alive again.
Riddle turned the Basilisk loose on the school and injured many.
The last victim was a student named Myrtle Warren, who was killed in the Girls' Bathroom.