Queen Moon

Queen Moon Butterfly, also known as Moon the Undaunted, is the 36th Queen of the Kingdom of Mewni, ruling alongside her husband King Butterfly, and the mother of Star Butterfly. She was the previous wielder of the royal magic wand before passing it down to her daughter on her fourteenth birthday. As of the end of Season 3, Moon has gone missing and is currently being searched for by Star and her friends. She is voiced by Grey DeLisle (Vicky, Sam Manson, and Mandy).

Personality
Queen Butterfly is serious most of the time, having a low tolerance for anything messy or destructive. In "Royal Pain", she was said to have kicked her husband out of the castle for not cleaning up his messes. Queen Butterfly often regards safety and caution for Star as shown most prominently in Star vs. the Forces of Evil: The Battle for Mewni when they were forced on the run from Toffee.

Being the queen, Queen Butterfly acts as the true ruling monarch of Mewni and always has the well-being of her kingdom in mind, to the point she is unable to express interest in anything else. This often causes her to appear cold towards others. Despite her overbearing strictness, she truly cares for her daughter; after the near loss of the family wand, rather than show any anger or disappointment, she hugs Star, telling her daughter that she's just glad she's safe. Her concern for Star is also demonstrated in "Toffee" when she attacks Toffee for presumably killing Star.

Moon reveals in Star vs. the Forces of Evil: The Battle for Mewni that she used to be a "happy go-lucky girl" just like Star, but after Toffee and his army killed her mother and she inherited the throne, she became serious and mature to protect her kingdom and family. However, she sometimes shows signs of fear and nervousness, such as when meeting Eclipsa for the first time and when she first casts her darkest spell. Her fear of Eclipsa and her possible escape are also on display in "Toffee".

In "Puddle Defender" and "Total Eclipsa the Moon", Moon demonstrates that she is willing to have an open mind about those toward whom she has preconceived misconceptions, such as monsters and Eclipsa.

Role in the series
After turning up missing, she would be found by Saetha's Wedding in time to meet Star's new allies, The Shell Lodge Squad, and actually feels bad for Star's feelings about why she gave up the kingdom and didn't like that her royalty was a lie, because he free spirit didn't mesh well with her royal life, especially with how strict she was, and with what she was about to do with her in an immoral place like St. Olga's Reform School for Wayward Princesses, all for nothing, giving Star a quarter-life crisis, leaving her no choice but to agree with her.