Megan Williams is a 12-year-old girl who helps her pony friends in Ponyland. She's the bearer of the Rainbow of Light. Gentle and motherly, but also mature and resourceful, she acts as the Little Ponies' leader, and in times of crisis the ponies often fly across the rainbow to find her.
She lives with her siblings on a ranch where she keeps a horse named TJ, and a bull named Tauro.
She was first brought to Dream Valley by Firefly to help save her friends from and defeat Tirek. During her quest, she encounters the Sea Ponies and the Moochick, who gave her a heart-shaped locket which contains the Rainbow of Light. After defeating Tirek, Firefly took her back home, taking the locket with her.