text: This myth system includes an "Isle of Flames" located in the "Sea of the Two Knives.
full_question: This myth system includes an "Isle of Flames" located in the "Sea of the Two Knives." The underworld of this myth system contains a serpent with four bearded human heads on its back, known as the "devourer of spirits." In some tales, its first god created a child from his spit and another from his vomit, after creating himself on a primeval hill that rose from the cosmic ocean. In this system, the gods ruled on earth as kings during the "First Time," and five deities were born on five intercalary days that were won in a gamble with the moon. Each night, a god in this system takes the form Afu to travel through twelve provinces of the underworld, Duat, after a daily ride through the sky on a barque and a battle with the serpent Apep. For 10 points, name this myth system which includes the gods Atum, Thoth, and Ra.
first_sentence: This myth system includes an "Isle of Flames" located in the "Sea of the Two Knives.
raw_answer: Egyptian mythology [or Heliopolis; or Hermopolis; or Ennead; or Ogdoad]