The Sphinx was an entity that appeared at Thebes before Oedipus ruled and after Laius's ruler. She appeared after Laius left Thebes to consult with the oracle at Delphi. During his leave, Creon took charge of the city, and the Sphinx beset . She would prey on targets along a road to Thebes, and she would ask a challenging riddle to anyone who confronted her, and if they got it wrong she would devour them. Creon offered the crown of Thebes to anyone who could conquer the Sphinx.
Finally, the brave and clever Oedipus came to successfully thwart her riddle. He answered the riddle "What walks on four feet in the morning, two in the afternoon and three at night?" correctly, answering with "Man: as an infant, he crawls on all fours; as an adult, he walks on two legs and; in old age, he uses a walking stick."