There are some clear details that stay consistent:
• A prince named Azor Ahai appeared at a moment of great darkness.
• He had a flaming sword called Lightbringer.
• The sword was forged in a loving wife’s blood.
• Azor Ahai then used that sword to defeat the “Great Other.”
• Then a prophecy called “The Prince Who Was Promised” was written in high Valyrian.
• It says that Azor Ahai would one day return.
• He would be born from the line of House Targaryen.
• And he would once again wield Lightbringer to conquer the darkness.
And Melisandre eventually adds some more details to the Azor Ahai myth:
• He appears after a long summer, when the stars bleed and the cold breath of darkness falls heavy on the world.
• He shall be born again amidst smoke and salt.
• He shall wake dragons out of stone.