Mystic Mother

The Mystic Mother is the Empress Of All Good Magic formally known as the feared Space Witch Rita Repulsa.

Dark Days
Before she became the Mystic Mother, she was an evil witch who was bent on destroying the world and the original Power Rangers. During the final assault on the universe, the wise wizard Zordon sacrificed his life in the form of an energy wave that spread across the galaxy destroying the United Alliance of Evil.

When the wave washed over Rita and her husband Lord Zedd, it destroyed their army but left her and Zedd alive as humans.

Mystic Force
Many years later, Rita Repulsa had regained her magical powers and was using them for good. She became the Empress of Good Magic and leader of the Mystic Ones. As the Mystic Mother, she gave the Mystic Force Rangers their link to the Morphing Grid and helped them in their quest to defeat evil mystic forces.

She was only seen in the two-part finale, Mystic Fate; after Octomus's control over Nick was broken, he went to the Mystic Dimension to put an end to all good magic by destroying her. The Snow Prince arrived to warn her to flee, but she refused, and attempted to fight off Octomus herself. She tried her strongest spell on the Master but it was no use. Octomus proved to be too strong, however, when he consumed her strongest spell, and then attempted to destroy her. She cast a spell on the Snow Prince to send him to inform the Rangers of what happened, and then was seemingly destroyed. Daggeron and Leanbow came to the Mystic Dimension to find her palace destroyed, and Octomus waiting for them. He destroyed them both with no effort, and then returned to earth to destroy the Rangers.

Revelation
However, it is later revealed that she survived his assault by transforming herself into undestroyable energy before his spell struck her, and then reforming. She later granted Clare the power of a true sorceress, and encouraged the Rangers immediately prior to their final battle with Octomus. Her last appearance is after Octomus's destruction, seemingly breaking the fourth wall as she says that the darkness is destroyed by light, "and should it ever return, your magic must stop it."

Mystic Mother continues to watch over those who serve all good magic.

Trivia

 * Rita frequently complains of having headaches when being defeated by the Power Rangers, a running gag that continues through all her appearances until her redemption in Countdown to Destruction. A callback to this gag is made in Power Rangers Mystic Force when Rita, now the Mystic Mother, tells Octomus "You are giving me a headache".