Mario + Rabbids Sparks of Hope

Sometime after the events of Mario + Rabbids: Kingdom Battle, the inhabitants of the Mushroom Kingdom, including Mario, Luigi, and Princess Peach, now peacefully coexist with the Rabbids and their Rabbid counterparts, who have all learnt to talk. The calm is suddenly broken when a horde of Rabbid-Luma hybrids called Sparks descend from the sky, pursued by a gigantic manta ray imbued with Darkmess, a shadowy corruptive substance. Rabbid Peach is accidentally abducted by the manta while attempting to take a selfie; Mario and their combat advisor drone Beep-0 free her from the Darkmess dimension inside the manta with the help of the Sparks. A malevolent entity known as Cursa then appears and attempts to destroy Mario, Rabbid Peach, and Beep-0, but the other heroes save them with a spaceship constructed from the Rabbids' Time Washing Machine called the WM-ARC. The ship's A.I., JEANIE, explains that the unique fusion of Rabbid and Luma DNA grants the Sparks unlimited power, and Cursa, whose corruptive influence has spread across the galaxy, wants to absorb that power for itself. The team resolves to find Cursa's stronghold and defeat them, saving as many Sparks and corrupted planets as possible, while also searching for Rosalina, the missing guardian of the Lumas.

Mario's team travels to five different planets while gathering enough Purified Darkmess Crystals to safely travel to Cursa's stronghold – Beacon Beach, Pristine Peaks, Palette Prime, Terra Flora, and Barrendale Mesa. They are joined by three new heroes along the way: Edge, a stoic sword-wielding Rabbid also looking to save the Sparks; Rabbid Rosalina, a gloomy but intelligent Rabbid who is trying to find her hero Rosalina; and Bowser, Mario’s perpetual archnemesis whose army has been brainwashed by Cursa. Together, they help the wardens of each world dispel the Darkmess infection while also battling Cursa's team of corrupted Rabbids, brainwashed minions of Bowser, and the Spark Hunters – three female Rabbid hybrids named Midnite, Bedrock, and Daphne. Near the end of their journey, Cursa once again attempts to destroy the heroes but unexpectedly transforms into Rosalina, whose body has been merged and possessed by Cursa's spirit. Rosalina gives the team a crystal and helps them escape before Cursa regains control; from the crystal, they learn that Cursa was originally a surviving fragment of the Megabug, which was cast out into space and was merged/empowered by space debris, eventually gaining sentience, desiring to feed upon the life energies of the galaxy to grow. It ambushed the Comet Observatory, home to Rosalina, the Lumas, and a group of Rabbids who came by on another Time Washing Machine, in an attempt to steal the space station's and the Lumas' power, but accidentally merged the Rabbids and Lumas together in a blast of energy when Rosalina sacrificed herself to ensure their safety, turning them into Sparks. Cursa needed to gather the Sparks' power in order to crush Rosalina's rebelling will against her possession.

The team reaches Cursa's stronghold and destroys its protective shield with one of the wardens' inventions, revealing the Comet Observatory. In a frantic attempt to stop them, Cursa creates Darkmess clones of Bowser and Edge derived from the Megabug's and Cursa's record of their DNA; Edge admits that she is also a creation of Cursa and was once the leader of the Spark Hunters, but betrayed her creator after gaining free will while her comrades maintained their loyalty to Cursa. Although she attempts to leave in shame, the other heroes refuse to cast her out and at last confront Cursa. After a protracted battle, Cursa releases both Rosalina and the energy of the absorbed Sparks but makes one last-ditch effort to destroy them in its true form. The nine heroes, the Sparks, and Rosalina all combine their power into a final attack, which eradicates Cursa for good. Everyone returns to the Mushroom Kingdom, where Rosalina congratulates them for their efforts in saving the Sparks, the galaxy, and herself. Both Rabbid Rosalina and Edge decide to stay with the heroes, and Rosalina gives a final thank-you to Mario and Bowser before departing. Rabbid Mario, Rabbid Luigi, and Rabbid Peach attempt to play with an irritated Bowser, forcing Mario to save them from his fire breath, and Beep-0 connects with the now-sentient JEANIE in a post-credits scene.

The heroes are summoned by Madame Bwahstrella, a fortune teller Rabbid from the main and previous games, to a large tower called the Tower of Doooom. She tasks them with rescuing Spawny, who is held hostage at the top of the tower by Cursa's minions. Once Spawny is rescued, he bids the heroes farewell and leaves to continue traveling the galaxy.

Taking place after defeating Daphne and before reaching Cursa's stronghold, the heroes travel to the musical Melodic Gardens after discovering that it has gone silent. The atmosphere, having been affected by the Darkmess, also prevents them from leaving. There, they meet Allegra, the planet's warden, who informs them of the threat. The villain responsible for this is revealed to be Kanya, a fourth Spark Hunter who Edge does not know of. Like Edge, she betrayed Cursa, but had evil plans of her own. Kanya then summons a robot resembling King Bob-omb to attack the heroes, but they manage to defeat it. Despite this, Kanya remains unfazed and leaves. Later, the heroes find Allegra's friend Dorrie, a dinosaur who is the source of the Melodic Gardens' biophonies, that are a part of the planet, imprisoned in a cage. Kanya arrives in a more powerful King Bob-omb mech, revealing that the one they defeated earlier was a prototype and that she was testing them earlier to make improvements to her final design. After freeing Dorrie, the heroes then defeat Kanya, who is then sent flying along with her mech. With the Melodic Gardens now back to normal, the heroes can now leave to confront Cursa as Allegra wishes them luck in their adventure.

This story takes place some time after the main story. Rayman receives a ticket to a movie studio called the Space Opera Network. Arriving there, he meets Rabbid Mario, Rabbid Peach, and Beep-0, who have also received tickets of their own. Rayman is uneasy towards the Rabbids due to his past encounters with them, but Beep-0 assures him that Rabbid Mario and Rabbid Peach are different. They learn that the studio is controlled by Phantom, an antagonist from the original game. Beep-0 assumes that he wants revenge for his previous defeat, but the Phantom claims that he has changed, though Beep-0 and Rayman do not fully trust him. Phantom reveals that it was he who summoned them here due to Darkmess infecting his studio and wants them to get rid of it. The group fight through hordes of Darkmess enemies throughout each studio set. Once all of it is gone, Phantom invites them to his control room, which is where the warp portal that brought the group here is located, but it is broken. Phantom then reveals the truth: he has been faking his redemption all along and does indeed want revenge, proving Rayman and Beep-0's suspicions correct. He wanted the heroes to get rid of the Darkmess so that he can carry out his revenge plan. As the heroes fight him, he mocks them with his singing. After they defeat him, the warp portal reactivates, allowing the heroes to return home. Rayman decides to remain at the studio to supervise the Rabbids here after seeing that they are now good. Rabbid Mario gives Rayman a hug while Rabbid Peach gives a present to him and Rayman does the same, showing that he is now on good terms with the Rabbids. In the credits, two photos are shown: one with the heroes showing their friends the gift that Rayman gave them (revealed to be one of Rayman's outfits) and the other showing Rayman wearing a Mario hat, which is the gift that Rabbid Peach gave him.