How did Medusa die?
Medusa had a special power: whoever looked at her would turn to stone. That's why, when fighting her, Perseus didn't look at her directly, he used his shield as a mirror to see what she was doing, and that's how he managed to cut off her head.
Athena Goddess of Intelligent War turned Medusa into a gorgon because she was a nymph that was having an affair with Poseidon God of the Sea. You see Medusa and Poseidon decided to meet inside Athena's temple. They had sex and Athena got angry and since Medusa had her sisters help her gain entrance to the temple Athena transformed them as well, but only Medusa was given immortality so she had to watch her sisters…
Medusa said she was so beautiful, even more beautiful than Athena and so Athena turned Medusa into a monster so that whenever the Medusa was looked at she would automatically turn them into stone, even herself, but then the Medusa was cheated on so this made the Medusa even more powerful and more angry towards her husband/Greek god. Then the Medusa was killed by Perseus who is a demigod Greek hero who killed Medusa.)