"Unveiling the Mystery: Mario's Absence in Mario + Rabbids Sparks of Hope Rayman DLC"

TL;DR
Mario is not playable in the Rayman DLC for Mario + Rabbids Sparks of Hope because the developers wanted to focus on the comedic dynamic between the Rabbids and Rayman. They felt that Mario's inclusion would make it feel like two separate IPs combined, whereas Rayman was treated as a guest character. The trio of Rabbid Mario, Rabbid Peach, and Rayman was chosen for their comedic synergy and narrative arc, gradually becoming a trio of heroes. The creative director also discussed why Rosalina wasn't playable in the main game and expressed interest in making a new Rayman game.
Why Mario isn't playable in the Mario + Rabbids Sparks of Hope Rayman DLC Nintendo Everything
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