Medusa (The Haunted Mansion)

Medusa is a minor character in the Disney Park attraction The Haunted Mansion, which appears in Disneyland in California, Walt Disney World in Florida, and Tokyo Disneyland, as well as Mystic Manor at Hong Kong Disneyland. Despite only scaring/attacking actual attraction, the character serves as a more prominent antagonist in the Haunted Mansion miniseries of the 2016 comic book series Disney Kingdoms by Marvel Comics.

Past
According to ancient Grecian myth, Medusa was a human woman who defiled the temple of the Goddess Athena. As punishment, she was transformed into a hideous monster who was so frightening and ugly, she would turn whoever gazed upon her face to turn to stone. She became a wrathful warrior until the day she was decapitated and killed by the demigod Perseus so that he may use her head to defeat the Kraken.

The Haunted Mansion
In the attraction, Edward is one of the ghosts possessing one of the Changing Portraits. It shows her, in her beautiful human form, standing in a Grecian courtyard. Whenever lightning strikes, it illuminates the portrait, revealing her as her true gorgon self, hissing evilly.

Mystic Manor
In Mystic Manor, a mosaic portrait of Medusa is brought to life by the magic Music Box. When guests pass by, it looks like her normal human self, but then will change into a growling, hissing gorgon form with red eyes that will attempt to attack.

Disney Kingdoms
In the Disney Kingdoms comic, Medusa and the other Changing Portrait ghouls serve the evil Captain, who has trapped all the ghosts in the mansion and is working to get all the ghosts to ally with him. She and the other Changing Portrait ghosts awaken when protagonist Danny Crowe arrives, and they all immediately try to kill him. They chase him through the mansion until they are scared off by Madame Leota. She presumably flees back into her portrait, leaving everyone alone until the Captain is destroyed.