Contains movie spoilers. Please refrain from playing if you haven't watched it.
Rosalina travels through space with the Lumas at the Comet Observatory. One night, while she is trying to put the Lumas to sleep, Bowser Jr. launches an attack, and Rosalina fights back. Meanwhile, Mario and Luigi, who restored peace to the Mushroom Kingdom after their battle with the Great Demon King Bowser, visit the desert land of Tostarena to investigate the source of a strange moaning sound coming from a pipe. There, they meet a cheerful and friendly Yoshi. Returning to the Mushroom Kingdom that evening, they attend a festival celebrating Princess Peach's birthday. Peach confides in Mario that she wants to know the truth about her origins. To find clues and save Rosalina, they decide to head for the Heaven's Door Galaxy. (Please be warned: contains movie spoilers.)
The dependable plumber of the Mushroom Kingdom. He faces galactic crises with his innate courage.
Mario's brother, who is easily frightened but brave when it counts. The bond between the brothers creates miracles.
The kind and strong princess of the Mushroom Kingdom. A cry for help from space leads to the secrets of her hidden past.
Princess Peach's reliable and brave explorer. He is fully prepared to provide support, no matter what dangers lie ahead!
After the battle with Mario and his friends, he was shrunk by a Blue Mushroom and imprisoned in Peach's Castle. Having not seen Jr. for years, he believes his son hates him. The former Great Demon King who once harbored ambitions of world conquest. He is trying to change his ways with Luigi's help, but...
A mother-like figure to the Lumas. She demonstrates wondrous abilities using the energy of the universe.
Cheerful "Star Children" who live in the Comet Observatory and adore Rosalina as their mother. They call Rosalina "Mama." The adventure begins when a troubled Luma asks for help.
Bowser's precious son. To gain the fame of being recognized by his father and to fulfill his father's dying wish, he executes a plan that shakes the entire universe. He calls Bowser "Papa." He commands the Bowser Troop to save his father. He is about the height of a human second-grader, and his age is around 8... (probably).
Mario and Luigi's new partner. He is very reliable but a bit of a glutton. With his long tongue and endless curiosity, he is very friendly and loves making new friends. He overcomes any difficulty by throwing eggs to defeat opponents! He is about the same size as Mario, large enough for Mario to ride on his back. He can only say "Yoshi!!" and conveys his feelings through cute cries.
The advisor Bowser relied on most. After Bowser was captured, he became the caretaker for Bowser Jr., a wizard who continues to support Jr. in becoming a magnificent villain.
In a galaxy far, far away...
The Comet Observatory
Release Date 2026.08.30 / Last Updated 2026.08.30