https://www.mariowiki.com/Super_Paper_Mario

Super Paper Mario is a platformer role-playing game released in 2007 for the Wii, as well as the first game starring Mario for the console. Unlike the other Paper Mario games, Super Paper Mario is a platformer and does not use a turn-based battle system, but rather incorporates RPG elements with platforming. The game fuses elements of 2D and 3D gameplay together, shifting back and forth between dimensions, once being described as a "2.5D" sidescroller by Nintendo Power magazine.